Maize value-added products play a crucial role in reducing post-harvest losses, enhancing food security, and generating income. While extensive research has focused on maize production in Cameroon, the exploration of ...Maize value-added products play a crucial role in reducing post-harvest losses, enhancing food security, and generating income. While extensive research has focused on maize production in Cameroon, the exploration of its value-added products and their profitability in the North-West Region remains underexplored. This study examined the profitability of maize value-added products in Mezam Division, with the objectives to: 1) identify various maize-based products, 2) assess the diversity of these products, 3) conduct a cost-benefit analysis of selected products, 4) examine the relationship between profitability and product diversity, and 5) identify key constraints impacting profitability. To achieve these objectives, structured questionnaires were administered to 500 small-scale maize entrepreneurs randomly selected from five subdivisions. Descriptive statistics were used to analyze objective 1 and 5, while the Shannon Diversity Index was employed to assess product diversity. Additionally, a cost-benefit analysis was conducted on four selected products namely pap, parched corn, peeled parboiled corn, and corn beer, and a correlation analysis was used to examine objective 4. In total, 13 maize value-added products were identified, with a diversity index of 4.4. The total cost of processing the four selected products per entrepreneur using 18 kg of maize per product was FCFA 83631.5 (US $132.75), while the total revenue was FCFA 121864.5 (US $193.43), resulting in an economic profit of FCFA 38,233 (US $60.69). Pap emerged as the most profitable product, with an economic profit of FCFA 27,875 (US $44.24), while corn beer was the least profitable, with an economic profit of FCFA 2133.46 (US $3.39). The correlation analysis revealed a strong negative relationship between product diversity and profitability (r = −0.91), indicating that entrepreneurs can maximize profitability by focusing on a few high-demand products like pap and parched corn. Key constraints to profitability included fluctuating market prices, high production costs, limited access to finance, and inadequate storage facilities. Despite these challenges, our findings indicate that maize value addition is profitable in Mezam Division. Entrepreneurs can leverage this data for informed decision-making and future investments. It is recommended that the government promote maize value addition and provide financial support for modern processing equipment to boost profitability and income generation.展开更多
Pythium stalk rot(PSR)is a destructive disease of maize,severely affecting yield and grain quality.The identification of quantitative trait loci(QTL)or genes for resistance to PSR forms the basis of diseaseresistant h...Pythium stalk rot(PSR)is a destructive disease of maize,severely affecting yield and grain quality.The identification of quantitative trait loci(QTL)or genes for resistance to PSR forms the basis of diseaseresistant hybrids breeding.In this study,a major QTL,Resistance to Pythium stalk rot 1(RPSR1),was identified from a set of recombinant inbred lines derived from MS71 and POP.Using a recombinant progeny testing strategy,RPSR1 was fine-mapped in a 472 kb interval.Through candidate gene expression,gene knock-down and knock-out studies,a leucine-rich repeat receptor-like kinase gene,PEP RECEPTOR 2(ZmPEPR2),was assigned as a PSR resistance gene.These results provide insights into the genetic architecture of resistance to PSR in maize,which should facilitate breeding maize for resistance to stalk rot.展开更多
Increasing concern over the amount of insecticide residues in food has encouraged research for ecologically sound strategies to effectively manage stored-product insect pests and protect living organisms and the envir...Increasing concern over the amount of insecticide residues in food has encouraged research for ecologically sound strategies to effectively manage stored-product insect pests and protect living organisms and the environment. Botanicals were evaluated as potential alternatives to control maize weevil, Sitophilus zeamais Motschulsky, in stored sorghum, Sorghum bicolor (L.) Moench. Beetles and moths of stored grain at farm and consumer levels damage 5 - 35% worldwide and >40% in tropical countries. Maize weevil is the most damaging storage insect of sorghum grain. Management of storage insects relies on insecticides that leave residues in food and the environment. Treatments were powders of neem bark, Azadirachta indica;mesquite pods, Prosopis glandulosa;milkweed leaves, Asclepias speciosa;and a check (no botanical powder). Eight newly emerged maize weevils were provided 5 g of Malisor-84 grain treated with three doses of each plant powder. Every 2 days, data were recorded on the number of adults killed by each treatment. Percentage killed was calculated by dose per treatment and compared with the check. Grain loss was calculated based on initial and final weights. LD50 was determined by probit analysis, and associations between variables were assessed by simple linear correlation. Powder of mesquite and milkweed at 0.2 g were more effective than neem or the check in killing S. zeamais (>90%) and reducing grain damage (34 - 35.2%) and weight loss (0.8%). Milkweed at 0.1 g and neem at 0.2 g killed 78.1% of weevils. Neem at 0.05 g was slow acting, resulting in 62.5% dead and more grain damage (59.5%) and weight loss (3.6%). Botanicals at low doses (LD50 = 0.2 - 0.4 g) showed efficacy in controlling maize weevils and are recommended alternatives to guarantee quantity and quality of stored cereal grains.展开更多
Maize is an important source of calories and protein in human lives in many countries of the world and is the main staple food in Africa, particularly in eastern Africa. In the Sudan, the low yield of maize was mainly...Maize is an important source of calories and protein in human lives in many countries of the world and is the main staple food in Africa, particularly in eastern Africa. In the Sudan, the low yield of maize was mainly due to the use of low yielding landraces. It is necessary to carry out breeding programs that deal with the production of high yielding, adaptable new varieties. Therefore, this study aimed to estimate genetic variability, heritability, genotypic performance and interrelationships among the traits. Ten maize genotypes evaluated at White Nile Research Station Farm, Kosti, of the Agricultural Research Corporation (ARC), Wad Medani Sudan were planted in a randomized complete block design with three replications during the two seasons of 2021 and 2022. Most evaluated genotypes exhibited a wide and significant variation in the 11 measured traits. Genotypic coefficient of variation and genetic advance were recorded for days to 50% tasseling, ear diameter (cm), number of grains per row and grain yield (t/ha) in both seasons. High heritability and genetic advance were recorded for grain yield, ear length, ear height, plant height, number of rows per ear, ear weight, days to 50% tasseling, 100-grain weight and days to 50% silking. Moreover, there was a highly significant and positive correlation of grain yield with number of rows per ear (r = 0.479), ear length (r = 0.381), 100-grain weight (r = 0.344) and days to 50% tasseling (r = 0.214). The highest yielding five genotypes across the seasons were TZCOM1/ZDPSYN (4.2 t/ha), EEPVAH-3 (4.2 t/ha), F2TWLY131228 (4.1 t/ha), PVA SYN6F2 (3.9 t/ha) and EEPVAH-9 (3.8 t/ha) these were needed to check the adaptability, stability and to test major maize growing areas to make sound recommendations for release.展开更多
Twenty short-statured maize inbred lines were collected from CIMMYT India and Mexico through the Plant Breeding Division, Bangladesh Agricultural Research Institute (BARI), Gazipur. The experiment was conducted from N...Twenty short-statured maize inbred lines were collected from CIMMYT India and Mexico through the Plant Breeding Division, Bangladesh Agricultural Research Institute (BARI), Gazipur. The experiment was conducted from November 2020 to April 2021 in three different agroecological regions such as BARI, Gazipur, RARS Barisal and RARS Rangpur. Seven inbred lines were selected on the basis of genetic diversity and per se performance and they were crossed separately in a 7 × 7 half diallel fashion, producing 21F1 hybrids in 2019 which were evaluated at three locations. However, variances due to GCA were much higher in magnitude than SCA for all the characters indicating preponderance of additive gene effects on the inheritance of these characters. Two parents viz., P3 (CML33) and P4 (CML41) were good general combiners and two crosses viz., P4 × P5 (CML41 × CML31) and P5 × P7 (CML31 × CML124) expressed significant positive SCA effects coupled with significant positive heterosis for grain yield and for most of the yield contributing characters over the two commercial check varieties BHM 9 and NK40. Four crosses: P1 × P5 (CML116 × CML31), P1 × P6 (CML116 × CML32), P2 × P6 (CML72 × CML32) and P3 × P4 (CML33 × CML41), exhibited significant and negative SCA effects for both plant and ear height which were desirable for short stature. Genotypes x location interaction was also significant for maximum characters, suggesting that genotypes interacted significantly in different environments.展开更多
Smallholder farming in West Africa faces various challenges, such as limited access to seeds, fertilizers, modern mechanization, and agricultural climate services. Crop productivity obtained under these conditions var...Smallholder farming in West Africa faces various challenges, such as limited access to seeds, fertilizers, modern mechanization, and agricultural climate services. Crop productivity obtained under these conditions varies significantly from one farmer to another, making it challenging to accurately estimate crop production through crop models. This limitation has implications for the reliability of using crop models as agricultural decision-making support tools. To support decision making in agriculture, an approach combining a genetic algorithm (GA) with the crop model AquaCrop is proposed for a location-specific calibration of maize cropping. In this approach, AquaCrop is used to simulate maize crop yield while the GA is used to derive optimal parameters set at grid cell resolution from various combinations of cultivar parameters and crop management in the process of crop and management options calibration. Statistics on pairwise simulated and observed yields indicate that the coefficient of determination varies from 0.20 to 0.65, with a yield deviation ranging from 8% to 36% across Burkina Faso (BF). An analysis of the optimal parameter sets shows that regardless of the climatic zone, a base temperature of 10˚C and an upper temperature of 32˚C is observed in at least 50% of grid cells. The growing season length and the harvest index vary significantly across BF, with the highest values found in the Soudanian zone and the lowest values in the Sahelian zone. Regarding management strategies, the fertility mean rate is approximately 35%, 39%, and 49% for the Sahelian, Soudano-sahelian, and Soudanian zones, respectively. The mean weed cover is around 36%, with the Sahelian and Soudano-sahelian zones showing the highest variability. The proposed approach can be an alternative to the conventional one-size-fits-all approach commonly used for regional crop modeling. Moreover, it has the potential to explore the performance of cropping strategies to adapt to changing climate conditions.展开更多
Phosphorylation is one of the major posttranslational modifications to control plant growth and development.Opaque2(O2)represents a central hub for endosperm filling,which largely determines seed yield and nutrient st...Phosphorylation is one of the major posttranslational modifications to control plant growth and development.Opaque2(O2)represents a central hub for endosperm filling,which largely determines seed yield and nutrient storage in maize.However,it still remains unclear how O2 phosphorylation orchestrates endosperm filling and nutrient quality.Here,we systematically identified the phosphorylation sites of O2 during endosperm filling.A total of 18 phosphorylation sites were found in O2 and five sites were identified to apparently modulate its subcellular localization and transactivation capacity.In addition,a conserved protein kinase CK1 was confirmed to interact with and phosphorylate O2 at the residue Threonine(T)202 to promote O2-mediated transactivation and protein stability.Overexpression of CK1 resulted in increased kernel size,100-kernel weight and nutrient storage.Phosphorylation-mimic O2 seeds at T202 exhibited enhanced kernel dimension,test weight,vitreous endosperm area and nutrient accumulation,whereas the phosphorylation-deficient O2 seeds did not.Collectively,this study establishes a comprehensive phosphocode atlas of O2 during endosperm filling and highlights the importance of phosphorylation modification in O2 to precisely orchestrate maize yield and nutrient quality.展开更多
Maize(Zea mays L.)is a monoecious grass species with separate male and female inflorescences which form the tassel and ear,respectively.The mature ear inflorescences usually bear hundreds of grains,so they directly in...Maize(Zea mays L.)is a monoecious grass species with separate male and female inflorescences which form the tassel and ear,respectively.The mature ear inflorescences usually bear hundreds of grains,so they directly influence maize grain production and yield.Here,we isolated a recessive maize mutant,tasselseed2016(ts2016),which exhibits pleiotropic inflorescence defects and reduced grain yield.These defects include the loss of determinacy and identity in meristems and floral organs,as well as a lack of the lower floret abortion in maize ear,and a smaller grain size.Using map-based cloning and allelic testing,we identified and confirmed the microRNA gene MIR172e as the target gene controlling these related traits.Furthermore,our evidence uncovered a new potential miR172e/ETHYLENE RESPONSIVE ELEMENT BINDING197(EREB197)regulatory module which controls lower floret abortion in maize ear.Transcriptome analysis revealed that the mutation of MIR172e represses multiple biological processes,particularly the flower development and hormone-related pathways in maize ear.We also found that a mutation in the DNA sequence of MIR172e affects RNA transcription,resulting in elongation blockage at the mutant site.Our results reveal the function and molecular mechanism of MIR172e in maize inflorescences and grain yield,and this study deepens our knowledge of maize inflorescence development.展开更多
Strip-till(ST),including straw mulching in the inter-row and localized fertilization in the intra-row,is a conservation tillage system for improving soil quality and crop growth.However,the yield advantage of maize un...Strip-till(ST),including straw mulching in the inter-row and localized fertilization in the intra-row,is a conservation tillage system for improving soil quality and crop growth.However,the yield advantage of maize under ST compared to conventional tillage(CT)remains unstable,and the strategies to increase maize yield under ST are unclear.This study aims to understand the physiological mechanism underlining maize yield formation under ST by comparing two maize cultivars,DKM753 and DK517,with contrasting yield performance in ST versus CT systems.Compared to CT,ST resulted in a 4.5%yield increase for DKM753 but a 5.6%decrease for DK517.These yield differences were primarily attributed to variations in grain number per ear(GN).During the rapid growth stage(V14-R3),i.e.,two weeks before and after silking,DKM753 showed a 6.7%increase in maximum growth rate(V_(max))and a 6.3%increase in average growth rate(V)under ST,whereas DK517 exhibited decline of 8.5%in V_(max) and 12.3%in V.Significant positive correlations are observed between V_(max) and V with GN under ST(R^(2)=0.79 and R^(2)=0.90,respectively).Enhanced dry matter accumulation in DKM753 under ST was attributed to increased leaf expansion rates,contributing to a larger photosynthate source.The straw mulching and localized nitrogen fertilization increased root-zone nitrogen availability at silking in ST compared to CT.DKM753 had a greater root system which made better use of the soil N and lead to an increased leaf nitrogen accumulation by 14.9%under ST.It is concluded that maize yield under the strip-till system is determined by grain number per ear,which can be increased by increasing nitrogen accumulation,plant growth,and ear development around silking stage.A sound root system can efficiently utilize soil nitrogen resources under the strip-till system,increasing plant nitrogen accumulation and thereby promoting plant growth.展开更多
Arogenate dehydratase(ADT)catalyzes the final step in phenylalanine synthesis and is crucial for plant development and metabolism.Previously,we demonstrated that the ADT/prephenate dehydratase ZmADT2 is essential for ...Arogenate dehydratase(ADT)catalyzes the final step in phenylalanine synthesis and is crucial for plant development and metabolism.Previously,we demonstrated that the ADT/prephenate dehydratase ZmADT2 is essential for maize resistance to Ustilago maydis and for overall plant development.In this study,we explored the role of ZmADT2 in maize kernel development.The mmsu mutant,a dysfunctional ZmADT2 variant,exhibits delayed embryo and endosperm development,along with deficiencies in carbohydrate and protein storage.Transcriptome analysis revealed differential expression of many kernel compartment-specific genes between mmsu and wild-type(WT)kernels,with impaired nutrient accumulation and auxin signaling pathway in the mmsu endosperm.Compared to WT,ZmADT2 mutation led to reduced auxin levels and smaller endosperm cell size.Exogenous auxin rescued the small kernel phenotype of mmsu.Additionally,auxin distribution was reduced in the basal endosperm transfer layer(BETL),causing defects in its development and function,including reduced transfer cell elongation,cell wall ingrowth and nutrient uptake.These findings suggest that ZmADT2 mediated mediates an auxin signaling pathway that is essential for maize kernel development.展开更多
Southern corn rust(SCR)is an airborne fungal disease caused by Puccinia polysora Underw.(P.polysora)that adversely impacts maize quality and yields worldwide.Screening for new elite SCR-resistant maize loci or genes h...Southern corn rust(SCR)is an airborne fungal disease caused by Puccinia polysora Underw.(P.polysora)that adversely impacts maize quality and yields worldwide.Screening for new elite SCR-resistant maize loci or genes has the potential to enhance overall resistance to this pathogen.Using phenotypic SCR resistance-related data collected over two years and three geographical environments,a genome-wide association study was carried out in this work,which eventually identified 91 loci that were substantially correlated with SCR susceptibility.These included 13 loci that were significant in at least three environments and overlapped with 74 candidate genes(B73_RefGen_v4).Comparative transcriptomic analyses were then performed to identify the genes related to SCR infection,with 2,586 and 797 differentially expressed genes(DEGs)ultimately being identified in the resistant Qi319and susceptible 8112 inbred lines following P.polysora infection,respectively,including 306 genes common to both lines.Subsequent integrative multi-omics investigations identified four potential candidate SCR response-related genes.One of these genes is ZmHCT9,which encodes the protein hydroxycinnamoyl transferase 9.This gene was up-regulated in susceptible inbred lines and linked to greater P.polysora resistance as confirmed through cucumber mosaic virus(CMV)-based virus induced-gene silencing(VIGS)system-mediated gene silencing.These data provide important insights into the genetic basis of the maize SCR response.They will be useful for for future research on potential genes related to SCR resistance in maize.展开更多
Meiosis,a critical process for sexual reproduction,requires precise regulation to ensure the correct progression of meiotic stages.In yeast and animals,errors in meiotic recombination and homologous chromosomes synaps...Meiosis,a critical process for sexual reproduction,requires precise regulation to ensure the correct progression of meiotic stages.In yeast and animals,errors in meiotic recombination and homologous chromosomes synapsis bring a surveillance mechanism named pachytene checkpoint to prevent pachytene exit.However,most plant mutants with defects in meiotic prophase I continue cell cycle progression,which hindered the characterization of factors controlling the prophase I to metaphase I transition.Here,we characterized a male-sterile mutant in maize,prolonged prophase1(pp1),which exhibited pachytene and diakinesis arrest in male meiosis,and abnormal chromatin condensation.Using mapbased cloning,the PP1 gene was isolated as a PHD family transcription factor,and its transcripts of PP1 were preferentially accumulated in tapetum and male germline cells during microsporogenesis.Transcriptomic analysis of the pp1 mutant revealed downregulation of genes associated with chromatin assembly,cell cycle,and male meiosis,correlating with observed meiotic arrest and chromatin condensation defects.These findings highlight the role of PP1 in maize microsporogenesis,and providing more insights into the mechanisms regulating the meiotic progression in maize.展开更多
Maize (Zea mays L.) is the world’s leading cereal crop, with production estimated at over 1 billion tonnes in 2022. In Côte d’Ivoire, maize is one of the most widely consumed foods, with national production exc...Maize (Zea mays L.) is the world’s leading cereal crop, with production estimated at over 1 billion tonnes in 2022. In Côte d’Ivoire, maize is one of the most widely consumed foods, with national production exceeding 1 million tonnes in 2022. Despite its importance, this crop is subject to numerous biotic constraints, including Maize streak virus (MSV). The objective of this study was to characterize MSV isolates from Côte d’Ivoire using molecular biology techniques. To achieve this, maize leaf samples displaying characteristic symptoms of MSV were collected from different agro-ecological zones (AEZs) of Côte d’Ivoire. Total DNA was extracted from the collected samples using the CTAB method and quantified with a Nanodrop spectrophotometer. The C2 region of the MSV genome’s open reading frame (ORF) was amplified through polymerase chain reaction (PCR) using MSV-specific primers. The resulting PCR products were sequenced using the Sanger method. Bioinformatics analysis was performed using MSV sequences from other African countries (retrieved from NCBI) alongside sequences obtained in this study. The analysis was conducted using MEGA X version 10.05 software. The results showed that the main symptoms observed in the field included the presence of longitudinal light green streaks on leaves, stunted plant growth, and incomplete seed development in infected plants. Phylogenetic analysis of the sequences from Côte d’Ivoire revealed three monophyletic groups, with sequences of some isolates collected from the same plot belonging to different groups. The MSV sequences from Côte d’Ivoire are very close to those from Rwanda. This study underscores the need for further investigation into the genetic diversity of MSV strains to enhance the diagnosis and management of this viral disease, which is particularly prevalent in maize crops in Côte d’Ivoire.展开更多
Nitrogen (N) is a crucial nutrient vital for the growth and productivity of maize. However, excessive nitrogen application can result in numerous environmental and ecological problems, such as water pollution, biodive...Nitrogen (N) is a crucial nutrient vital for the growth and productivity of maize. However, excessive nitrogen application can result in numerous environmental and ecological problems, such as water pollution, biodiversity loss, and greenhouse gas emissions. Therefore, breeding maize hybrids resilient to low nitrogen conditions is crucial for sustainable agriculture, especially under low nitrogen conditions. Consequently, this study aimed to evaluate the combining ability and heterosis of maize lines, recognize promising hybrids, and study gene action controlling key traits under low and recommended N stress conditions. The half-diallel mating design hybridized seven maize inbreds, resulting in 21 F1 hybrids. These hybrids, along with two high-yielding commercial hybrids (SC10 and TWC310), were evaluated in field trials under recommended (290 kg/ha) and low N (166 kg N/ha) conditions. Significant variations were observed among assessed hybrids for all measured traits, with non-additive gene action being predominant for grain yield and its related characteristics under recommended and low N conditions. Inbred lines P105 and P106 were recognized as effective combiners for earliness, with P105 also excelling in shorter plant height and lower ear placement. In addition, P101, P102, and P104 were identified as good combiners for increasing grain yield and related attributes under low N conditions. The crosses P105 × P106 and P106 × P107 demonstrated outstanding heterotic effects for earliness, while hybrids P101 × P102 and P102 × P104 exhibited remarkable heterotic effects for grain yield low nitrogen stress conditions. These promising hybrids could be considered for commercial use after further evaluation. Strong positive correlations were found between grain yield and ear height, plant height, number of kernels per row, and 1000-grain weight, highlighting their importance for indirect selection to enhance the grain yield of maize under low N stress conditions.展开更多
A four-year field experiment was conducted with two cultivars and four N rate to investigate the spatiotemporal characteristics of leaf senescence in maize after silking and its response to N fertilizer rates on them,...A four-year field experiment was conducted with two cultivars and four N rate to investigate the spatiotemporal characteristics of leaf senescence in maize after silking and its response to N fertilizer rates on them,as well as to reveal the differences in post-silking chlorophyll degradation between low-N-tolerant cultivars.The results showed that the order of leaf senescence after silking in maize was lower leaf>upper leaf>ear leaf,leaf tip>middle>base.Increasing N fertilizer down-regulated the expression of ZmCLH2 and ZmPPH in the leaves at 10-30 d after silking,reducing CLH and PPH activities,thereby delaying the leaf senescence.These effects were more prominent in low-N-sensitive cultivar Xianyu 508(XY508)than in low-N-tolerant cultivar Zhenghong 311(ZH311),especially in the lower leaves and leaf tip.Under low N condition,leaf yellowing and chlorophyll degradation occurred later and slower in ZH311 than in XY508.This resulted in a higher post-silking dry matter accumulation and grain yield in ZH311,which may be one of the important physiological bases of low nitrogen tolerant cultivars.Future research should focus on developing low-N-tolerant maize cultivars with slower leaf senescence near the ear after silking.展开更多
The distributions of light and nitrogen within a plant's canopy reflect the growth adaptation of crops to the environment and are conducive to improving the carbon assimilation ability.So can the yield in crop pro...The distributions of light and nitrogen within a plant's canopy reflect the growth adaptation of crops to the environment and are conducive to improving the carbon assimilation ability.So can the yield in crop production be maximized by improving the light and nitrogen distributions without adding any additional inputs?In this study,the effects of different nitrogen application rates and planting densities on the canopy light and nitrogen distributions of two highyielding maize cultivars(XY335 and DH618)and the regulatory effects of canopy physiological characteristics on radiation use efficiency(RUE)and yield were studied based on high-yield field experiments in Qitai,Xinjiang Uygur Autonomous Region,China,during 2019 and 2020.The results showed that the distribution of photosynthetically active photon flux density(PPFD)in the maize canopy decreased from top to bottom,while the vertical distribution of specific leaf nitrogen(SLN)initially increased and then decreased from top to bottom in the canopy.When SLN began to decrease,the PPDF values of XY335 and DH618 were 0.5 and 0.3,respectively,corresponding to 40.6 and49.3%of the total leaf area index(LAI).Nitrogen extinction coefficient(K_(N))/light extinction coefficient(K_(L))ratio in the middle and lower canopy of XY335(0.32)was 0.08 higher than that of DH618(0.24).The yield and RUE of XY335(17.2 t ha^(-1)and 1.8g MJ^(-1))were 7.0%(1.1 t ha^(-1))and 13.7%(0.2 g MJ^(-1))higher than those of DH618(16.1 t ha^(-1)and 1.6 g MJ^(-1)).Therefore,better light conditions(where the proportion of LAI in the upper and middle canopy was small)improved the light distribution when SLN started to decline,thus helping to mobilize the nitrogen distribution and maintain a high K_(N)and K_(N)/K_(L)ratio.In addition,K_(N)/K_(L)was a key parameter for yield improvement when the maize nutrient requirements were met at 360 kg N ha^(-1).At this level,an appropriately optimized high planting density could promote nitrogen utilization and produce higher yields and greater efficiency.The results of this study will be important for achieving high maize yields and the high efficiency cultivation and breeding of maize in the future.展开更多
In view of the problems that the drilling depth can not be adjusted and the amount of liquid injection can not be accurately modulated in the local test device of maize variety breeding and disease resistance,combinin...In view of the problems that the drilling depth can not be adjusted and the amount of liquid injection can not be accurately modulated in the local test device of maize variety breeding and disease resistance,combining the test technical requirements of drilling,liquid injection and sealing of the penultimate radial pitch of maize straw from the ground,a quantitative adjustable liquid injection device for maize stalk center borehole was designed.Its structure,working principle,key technical parameters and practical application effect were elaborated in detail.The field experiment demonstrated that the quantitative adjustable liquid injection device for maize stalk center borehole could meet the requirements of the local test of maize stalk rot.展开更多
We used field experimental data to evaluate the ability of the agricultural production system model (APSIM) to simulate soil P availability,maize biomass and grain yield in response to P fertilizer applications on a f...We used field experimental data to evaluate the ability of the agricultural production system model (APSIM) to simulate soil P availability,maize biomass and grain yield in response to P fertilizer applications on a fluvo-aquic soil in the North China Plain.Crop and soil data from a 2-year experiment with three P fertilizer application rates(0,75 and 300 kg P_(2)O_(5) ha^(–1)) were used to calibrate the model.Sensitivity analysis was carried out to investigate the influence of APSIM SoilP parameters on the simulated P availability in soil and maize growth.Crop and soil P parameters were then derived by matching or relating the simulation results to observed crop biomass,yield,P uptake and Olsen-P in soil.The re-parameterized model was further validated against 2 years of independent data at the same sites.The re-parameterized model enabled good simulation of the maize leaf area index (LAI),biomass,grain yield,P uptake,and grain P content in response to different levels of P additions against both the calibration and validation datasets.Our results showed that APSIM needs to be re-parameterized for simulation of maize LAI dynamics through modification of leaf size curve and a reduction in the rate of leaf senescence for modern staygreen maize cultivars in China.The P concentration limits (maximum and minimum P concentrations in organs)at different stages also need to be adjusted.Our results further showed a curvilinear relationship between the measured Olsen-P concentration and simulated labile P content,which could facilitate the initialization of APSIM P pools in the NCP with Olsen-P measurements in future studies.It remains difficult to parameterize the APSIM SoilP module due to the conceptual nature of the pools and simplified conceptualization of key P transformation processes.A fundamental understanding still needs to be developed for modelling and predicting the fate of applied P fertilizers in soils with contrasting physical and chemical characteristics.展开更多
Developing high-yield maize hybrids is critical for sustaining maize production,especially in the face of rapid climate changes and the growing global population.Exploring the genetic diversity and combining ability i...Developing high-yield maize hybrids is critical for sustaining maize production,especially in the face of rapid climate changes and the growing global population.Exploring the genetic diversity and combining ability in parental inbreds is needed for developing such high-yielding hybrids.Consequently,this study aimed at evaluating parental genetic diversity employing simple sequence repeats(SSR)markers,estimating effects of general(GCA)and specific(SCA)combining abilities for grain yield and yield contributing characters,identifying high yielding hybrids,and evaluating the association of SCA effects and performance of hybrids with genetic distance.Half-diallel mating scheme was utilized to develop 21 F_(1) hybrids from seven diverse maize inbred lines.The F_(1) hybrids along with check hybrid(SC-10),were investigated in a field trial over two growing seasons under arid conditions.The assessed F_(1) hybrids displayed significant genetic variations across all recorded traits.The inbreds P_(1) and P_(3) were detected as effective combiners to develop early maturing hybrids.Additionally,P_(3) and P_(4) were recognized as better combiners for improving grain yield and yield attributed characters.The hybrids P_(1)×P_(5) and P_(4)×P_(7) displayed significant SCA effects coupled with favorable agronomic performance.These hybrids are recommended for further evaluation and release as variety for arid environments to increase total maize production and contribute to food security.The alleles per locus differed between 2 and 5,with average of 3.5 alleles/locus.The polymorphic information content(PIC)altered between 0.21 to 0.74,with a mean of 0.56.Unweighted neighbor-joining tree grouped the inbred lines into three clusters,providing a valuable tool to decrease the crosses needed to be assessed in the trial field.Parental genetic distance varied from 0.63 to 0.90,averaging 0.79.The relationship between genetic diversity assessed through SSR markers and SCA effects was insignificant for all considered traits.Otherwise,SCA demonstrated a significant correlation with hybrid performance,suggesting that SCA serves as a reliable predictor for hybrid performance.The assessed maize inbred lines and developed hybrids revealed substantial genetic variability,offering valuable resources for enhancing maize productivity under arid conditions.The identified promising inbred lines(P_(1),P_(3),and P_(4))might be regarded as effective combiners for developing early-maturing genotypes and excellent combiners for enhancing yield attributes.Notably,the developed hybrids P_(1)×P_(5) and P_(4)×P_(7) possessed significant SCA alongside superior yield traits.SCA demonstrated a significant correlation with hybrid performance,suggesting its potential as a reliable predictor for the performance of developed hybrids.展开更多
The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.H...The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.However,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains unknown.This study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to 2021.The treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N supply.When water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme activities.Compared with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improved urease activity and nitrate reductase activity by 5.4% at the R2(blister)stage and 19.6% at the V6(6th leaf)stage,and increased net income and the benefit:cost ratio by 22.1 and 16.7%,respectively.W1N1D2 and W1N2D2 reduced the nitrate nitrogen and ammoniacal nitrogen contents at the R6 stage in the 40-100 cm soil layer,compared with W2N2D1.In summary,increasing the planting density by 30% can compensate for the loss of grain yield and aboveground N accumulation under reduced water and N inputs.Meanwhile,increasing the maize density by 30% improved grain yield and aboveground N accumulation when water was reduced by 20% while the N application rate remained constant in arid irrigation areas.展开更多
文摘Maize value-added products play a crucial role in reducing post-harvest losses, enhancing food security, and generating income. While extensive research has focused on maize production in Cameroon, the exploration of its value-added products and their profitability in the North-West Region remains underexplored. This study examined the profitability of maize value-added products in Mezam Division, with the objectives to: 1) identify various maize-based products, 2) assess the diversity of these products, 3) conduct a cost-benefit analysis of selected products, 4) examine the relationship between profitability and product diversity, and 5) identify key constraints impacting profitability. To achieve these objectives, structured questionnaires were administered to 500 small-scale maize entrepreneurs randomly selected from five subdivisions. Descriptive statistics were used to analyze objective 1 and 5, while the Shannon Diversity Index was employed to assess product diversity. Additionally, a cost-benefit analysis was conducted on four selected products namely pap, parched corn, peeled parboiled corn, and corn beer, and a correlation analysis was used to examine objective 4. In total, 13 maize value-added products were identified, with a diversity index of 4.4. The total cost of processing the four selected products per entrepreneur using 18 kg of maize per product was FCFA 83631.5 (US $132.75), while the total revenue was FCFA 121864.5 (US $193.43), resulting in an economic profit of FCFA 38,233 (US $60.69). Pap emerged as the most profitable product, with an economic profit of FCFA 27,875 (US $44.24), while corn beer was the least profitable, with an economic profit of FCFA 2133.46 (US $3.39). The correlation analysis revealed a strong negative relationship between product diversity and profitability (r = −0.91), indicating that entrepreneurs can maximize profitability by focusing on a few high-demand products like pap and parched corn. Key constraints to profitability included fluctuating market prices, high production costs, limited access to finance, and inadequate storage facilities. Despite these challenges, our findings indicate that maize value addition is profitable in Mezam Division. Entrepreneurs can leverage this data for informed decision-making and future investments. It is recommended that the government promote maize value addition and provide financial support for modern processing equipment to boost profitability and income generation.
基金supported by National Natural Science Foundation of China(32302371 to Junbin Chen)the National Key Research and Development Program,Ministry of Science and Technology of China(2022YFD1201802 to Wangsheng Zhu)Research Program from State Key Laboratory of Maize Biobreeding(SKLMB2424 to Wangsheng Zhu).
文摘Pythium stalk rot(PSR)is a destructive disease of maize,severely affecting yield and grain quality.The identification of quantitative trait loci(QTL)or genes for resistance to PSR forms the basis of diseaseresistant hybrids breeding.In this study,a major QTL,Resistance to Pythium stalk rot 1(RPSR1),was identified from a set of recombinant inbred lines derived from MS71 and POP.Using a recombinant progeny testing strategy,RPSR1 was fine-mapped in a 472 kb interval.Through candidate gene expression,gene knock-down and knock-out studies,a leucine-rich repeat receptor-like kinase gene,PEP RECEPTOR 2(ZmPEPR2),was assigned as a PSR resistance gene.These results provide insights into the genetic architecture of resistance to PSR in maize,which should facilitate breeding maize for resistance to stalk rot.
文摘Increasing concern over the amount of insecticide residues in food has encouraged research for ecologically sound strategies to effectively manage stored-product insect pests and protect living organisms and the environment. Botanicals were evaluated as potential alternatives to control maize weevil, Sitophilus zeamais Motschulsky, in stored sorghum, Sorghum bicolor (L.) Moench. Beetles and moths of stored grain at farm and consumer levels damage 5 - 35% worldwide and >40% in tropical countries. Maize weevil is the most damaging storage insect of sorghum grain. Management of storage insects relies on insecticides that leave residues in food and the environment. Treatments were powders of neem bark, Azadirachta indica;mesquite pods, Prosopis glandulosa;milkweed leaves, Asclepias speciosa;and a check (no botanical powder). Eight newly emerged maize weevils were provided 5 g of Malisor-84 grain treated with three doses of each plant powder. Every 2 days, data were recorded on the number of adults killed by each treatment. Percentage killed was calculated by dose per treatment and compared with the check. Grain loss was calculated based on initial and final weights. LD50 was determined by probit analysis, and associations between variables were assessed by simple linear correlation. Powder of mesquite and milkweed at 0.2 g were more effective than neem or the check in killing S. zeamais (>90%) and reducing grain damage (34 - 35.2%) and weight loss (0.8%). Milkweed at 0.1 g and neem at 0.2 g killed 78.1% of weevils. Neem at 0.05 g was slow acting, resulting in 62.5% dead and more grain damage (59.5%) and weight loss (3.6%). Botanicals at low doses (LD50 = 0.2 - 0.4 g) showed efficacy in controlling maize weevils and are recommended alternatives to guarantee quantity and quality of stored cereal grains.
文摘Maize is an important source of calories and protein in human lives in many countries of the world and is the main staple food in Africa, particularly in eastern Africa. In the Sudan, the low yield of maize was mainly due to the use of low yielding landraces. It is necessary to carry out breeding programs that deal with the production of high yielding, adaptable new varieties. Therefore, this study aimed to estimate genetic variability, heritability, genotypic performance and interrelationships among the traits. Ten maize genotypes evaluated at White Nile Research Station Farm, Kosti, of the Agricultural Research Corporation (ARC), Wad Medani Sudan were planted in a randomized complete block design with three replications during the two seasons of 2021 and 2022. Most evaluated genotypes exhibited a wide and significant variation in the 11 measured traits. Genotypic coefficient of variation and genetic advance were recorded for days to 50% tasseling, ear diameter (cm), number of grains per row and grain yield (t/ha) in both seasons. High heritability and genetic advance were recorded for grain yield, ear length, ear height, plant height, number of rows per ear, ear weight, days to 50% tasseling, 100-grain weight and days to 50% silking. Moreover, there was a highly significant and positive correlation of grain yield with number of rows per ear (r = 0.479), ear length (r = 0.381), 100-grain weight (r = 0.344) and days to 50% tasseling (r = 0.214). The highest yielding five genotypes across the seasons were TZCOM1/ZDPSYN (4.2 t/ha), EEPVAH-3 (4.2 t/ha), F2TWLY131228 (4.1 t/ha), PVA SYN6F2 (3.9 t/ha) and EEPVAH-9 (3.8 t/ha) these were needed to check the adaptability, stability and to test major maize growing areas to make sound recommendations for release.
文摘Twenty short-statured maize inbred lines were collected from CIMMYT India and Mexico through the Plant Breeding Division, Bangladesh Agricultural Research Institute (BARI), Gazipur. The experiment was conducted from November 2020 to April 2021 in three different agroecological regions such as BARI, Gazipur, RARS Barisal and RARS Rangpur. Seven inbred lines were selected on the basis of genetic diversity and per se performance and they were crossed separately in a 7 × 7 half diallel fashion, producing 21F1 hybrids in 2019 which were evaluated at three locations. However, variances due to GCA were much higher in magnitude than SCA for all the characters indicating preponderance of additive gene effects on the inheritance of these characters. Two parents viz., P3 (CML33) and P4 (CML41) were good general combiners and two crosses viz., P4 × P5 (CML41 × CML31) and P5 × P7 (CML31 × CML124) expressed significant positive SCA effects coupled with significant positive heterosis for grain yield and for most of the yield contributing characters over the two commercial check varieties BHM 9 and NK40. Four crosses: P1 × P5 (CML116 × CML31), P1 × P6 (CML116 × CML32), P2 × P6 (CML72 × CML32) and P3 × P4 (CML33 × CML41), exhibited significant and negative SCA effects for both plant and ear height which were desirable for short stature. Genotypes x location interaction was also significant for maximum characters, suggesting that genotypes interacted significantly in different environments.
文摘Smallholder farming in West Africa faces various challenges, such as limited access to seeds, fertilizers, modern mechanization, and agricultural climate services. Crop productivity obtained under these conditions varies significantly from one farmer to another, making it challenging to accurately estimate crop production through crop models. This limitation has implications for the reliability of using crop models as agricultural decision-making support tools. To support decision making in agriculture, an approach combining a genetic algorithm (GA) with the crop model AquaCrop is proposed for a location-specific calibration of maize cropping. In this approach, AquaCrop is used to simulate maize crop yield while the GA is used to derive optimal parameters set at grid cell resolution from various combinations of cultivar parameters and crop management in the process of crop and management options calibration. Statistics on pairwise simulated and observed yields indicate that the coefficient of determination varies from 0.20 to 0.65, with a yield deviation ranging from 8% to 36% across Burkina Faso (BF). An analysis of the optimal parameter sets shows that regardless of the climatic zone, a base temperature of 10˚C and an upper temperature of 32˚C is observed in at least 50% of grid cells. The growing season length and the harvest index vary significantly across BF, with the highest values found in the Soudanian zone and the lowest values in the Sahelian zone. Regarding management strategies, the fertility mean rate is approximately 35%, 39%, and 49% for the Sahelian, Soudano-sahelian, and Soudanian zones, respectively. The mean weed cover is around 36%, with the Sahelian and Soudano-sahelian zones showing the highest variability. The proposed approach can be an alternative to the conventional one-size-fits-all approach commonly used for regional crop modeling. Moreover, it has the potential to explore the performance of cropping strategies to adapt to changing climate conditions.
基金supported by Biological Breeding-National Science and Technology Major Project(2023ZD04069)Young Scientist Project(2023YFD1200008)+2 种基金the National Natural Science Foundation of China(32472122)Sichuan Provincial General Project(24NSFSC1704)the Open Project Program and Biological Breeding Program of State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China(SKL-ZY202211).
文摘Phosphorylation is one of the major posttranslational modifications to control plant growth and development.Opaque2(O2)represents a central hub for endosperm filling,which largely determines seed yield and nutrient storage in maize.However,it still remains unclear how O2 phosphorylation orchestrates endosperm filling and nutrient quality.Here,we systematically identified the phosphorylation sites of O2 during endosperm filling.A total of 18 phosphorylation sites were found in O2 and five sites were identified to apparently modulate its subcellular localization and transactivation capacity.In addition,a conserved protein kinase CK1 was confirmed to interact with and phosphorylate O2 at the residue Threonine(T)202 to promote O2-mediated transactivation and protein stability.Overexpression of CK1 resulted in increased kernel size,100-kernel weight and nutrient storage.Phosphorylation-mimic O2 seeds at T202 exhibited enhanced kernel dimension,test weight,vitreous endosperm area and nutrient accumulation,whereas the phosphorylation-deficient O2 seeds did not.Collectively,this study establishes a comprehensive phosphocode atlas of O2 during endosperm filling and highlights the importance of phosphorylation modification in O2 to precisely orchestrate maize yield and nutrient quality.
基金supported by the Natural Science Foundation of Henan Province,China(232300421260)the Tackling Key Problems in Science and Technology of Henan Province,China(222102110465,to LZ and 232102111097,to YS)the Open Project Program(SKL-KF202214)。
文摘Maize(Zea mays L.)is a monoecious grass species with separate male and female inflorescences which form the tassel and ear,respectively.The mature ear inflorescences usually bear hundreds of grains,so they directly influence maize grain production and yield.Here,we isolated a recessive maize mutant,tasselseed2016(ts2016),which exhibits pleiotropic inflorescence defects and reduced grain yield.These defects include the loss of determinacy and identity in meristems and floral organs,as well as a lack of the lower floret abortion in maize ear,and a smaller grain size.Using map-based cloning and allelic testing,we identified and confirmed the microRNA gene MIR172e as the target gene controlling these related traits.Furthermore,our evidence uncovered a new potential miR172e/ETHYLENE RESPONSIVE ELEMENT BINDING197(EREB197)regulatory module which controls lower floret abortion in maize ear.Transcriptome analysis revealed that the mutation of MIR172e represses multiple biological processes,particularly the flower development and hormone-related pathways in maize ear.We also found that a mutation in the DNA sequence of MIR172e affects RNA transcription,resulting in elongation blockage at the mutant site.Our results reveal the function and molecular mechanism of MIR172e in maize inflorescences and grain yield,and this study deepens our knowledge of maize inflorescence development.
基金the National Key Research and Development Program of China(2022YFD1500705)National Natural Science Foundation of China(U19A2035)for financial support。
文摘Strip-till(ST),including straw mulching in the inter-row and localized fertilization in the intra-row,is a conservation tillage system for improving soil quality and crop growth.However,the yield advantage of maize under ST compared to conventional tillage(CT)remains unstable,and the strategies to increase maize yield under ST are unclear.This study aims to understand the physiological mechanism underlining maize yield formation under ST by comparing two maize cultivars,DKM753 and DK517,with contrasting yield performance in ST versus CT systems.Compared to CT,ST resulted in a 4.5%yield increase for DKM753 but a 5.6%decrease for DK517.These yield differences were primarily attributed to variations in grain number per ear(GN).During the rapid growth stage(V14-R3),i.e.,two weeks before and after silking,DKM753 showed a 6.7%increase in maximum growth rate(V_(max))and a 6.3%increase in average growth rate(V)under ST,whereas DK517 exhibited decline of 8.5%in V_(max) and 12.3%in V.Significant positive correlations are observed between V_(max) and V with GN under ST(R^(2)=0.79 and R^(2)=0.90,respectively).Enhanced dry matter accumulation in DKM753 under ST was attributed to increased leaf expansion rates,contributing to a larger photosynthate source.The straw mulching and localized nitrogen fertilization increased root-zone nitrogen availability at silking in ST compared to CT.DKM753 had a greater root system which made better use of the soil N and lead to an increased leaf nitrogen accumulation by 14.9%under ST.It is concluded that maize yield under the strip-till system is determined by grain number per ear,which can be increased by increasing nitrogen accumulation,plant growth,and ear development around silking stage.A sound root system can efficiently utilize soil nitrogen resources under the strip-till system,increasing plant nitrogen accumulation and thereby promoting plant growth.
基金funded by the National Natural Science Foundation of China(32071921)Key R&D Program of Shandong Province,China(2021LZGC022)Taishan Scholars Project(ts201712024).
文摘Arogenate dehydratase(ADT)catalyzes the final step in phenylalanine synthesis and is crucial for plant development and metabolism.Previously,we demonstrated that the ADT/prephenate dehydratase ZmADT2 is essential for maize resistance to Ustilago maydis and for overall plant development.In this study,we explored the role of ZmADT2 in maize kernel development.The mmsu mutant,a dysfunctional ZmADT2 variant,exhibits delayed embryo and endosperm development,along with deficiencies in carbohydrate and protein storage.Transcriptome analysis revealed differential expression of many kernel compartment-specific genes between mmsu and wild-type(WT)kernels,with impaired nutrient accumulation and auxin signaling pathway in the mmsu endosperm.Compared to WT,ZmADT2 mutation led to reduced auxin levels and smaller endosperm cell size.Exogenous auxin rescued the small kernel phenotype of mmsu.Additionally,auxin distribution was reduced in the basal endosperm transfer layer(BETL),causing defects in its development and function,including reduced transfer cell elongation,cell wall ingrowth and nutrient uptake.These findings suggest that ZmADT2 mediated mediates an auxin signaling pathway that is essential for maize kernel development.
基金supported by the National Key R&D Program of China(2022YFD1201802)the Shandong Key R&D Program,China(2022CXGC010607)+2 种基金the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(CAAS-ZDRW202109)the Agricultural Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(CAAS-ASTIP2017-ICS)the Subproject of the Major Project of Science and Technology in Shanxi Province,China(202201140601025-1-02)。
文摘Southern corn rust(SCR)is an airborne fungal disease caused by Puccinia polysora Underw.(P.polysora)that adversely impacts maize quality and yields worldwide.Screening for new elite SCR-resistant maize loci or genes has the potential to enhance overall resistance to this pathogen.Using phenotypic SCR resistance-related data collected over two years and three geographical environments,a genome-wide association study was carried out in this work,which eventually identified 91 loci that were substantially correlated with SCR susceptibility.These included 13 loci that were significant in at least three environments and overlapped with 74 candidate genes(B73_RefGen_v4).Comparative transcriptomic analyses were then performed to identify the genes related to SCR infection,with 2,586 and 797 differentially expressed genes(DEGs)ultimately being identified in the resistant Qi319and susceptible 8112 inbred lines following P.polysora infection,respectively,including 306 genes common to both lines.Subsequent integrative multi-omics investigations identified four potential candidate SCR response-related genes.One of these genes is ZmHCT9,which encodes the protein hydroxycinnamoyl transferase 9.This gene was up-regulated in susceptible inbred lines and linked to greater P.polysora resistance as confirmed through cucumber mosaic virus(CMV)-based virus induced-gene silencing(VIGS)system-mediated gene silencing.These data provide important insights into the genetic basis of the maize SCR response.They will be useful for for future research on potential genes related to SCR resistance in maize.
基金supported by National Key Research and Development Program of China(2022YFF1003501)Biological BreedingMajor Projects(2023ZD04076)+1 种基金Funds from State Key Laboratory of Maize Bio-breeding(SKLMB2404,SKLMB2440)Anhui Natural Science Foundation(2308085QC92).
文摘Meiosis,a critical process for sexual reproduction,requires precise regulation to ensure the correct progression of meiotic stages.In yeast and animals,errors in meiotic recombination and homologous chromosomes synapsis bring a surveillance mechanism named pachytene checkpoint to prevent pachytene exit.However,most plant mutants with defects in meiotic prophase I continue cell cycle progression,which hindered the characterization of factors controlling the prophase I to metaphase I transition.Here,we characterized a male-sterile mutant in maize,prolonged prophase1(pp1),which exhibited pachytene and diakinesis arrest in male meiosis,and abnormal chromatin condensation.Using mapbased cloning,the PP1 gene was isolated as a PHD family transcription factor,and its transcripts of PP1 were preferentially accumulated in tapetum and male germline cells during microsporogenesis.Transcriptomic analysis of the pp1 mutant revealed downregulation of genes associated with chromatin assembly,cell cycle,and male meiosis,correlating with observed meiotic arrest and chromatin condensation defects.These findings highlight the role of PP1 in maize microsporogenesis,and providing more insights into the mechanisms regulating the meiotic progression in maize.
文摘Maize (Zea mays L.) is the world’s leading cereal crop, with production estimated at over 1 billion tonnes in 2022. In Côte d’Ivoire, maize is one of the most widely consumed foods, with national production exceeding 1 million tonnes in 2022. Despite its importance, this crop is subject to numerous biotic constraints, including Maize streak virus (MSV). The objective of this study was to characterize MSV isolates from Côte d’Ivoire using molecular biology techniques. To achieve this, maize leaf samples displaying characteristic symptoms of MSV were collected from different agro-ecological zones (AEZs) of Côte d’Ivoire. Total DNA was extracted from the collected samples using the CTAB method and quantified with a Nanodrop spectrophotometer. The C2 region of the MSV genome’s open reading frame (ORF) was amplified through polymerase chain reaction (PCR) using MSV-specific primers. The resulting PCR products were sequenced using the Sanger method. Bioinformatics analysis was performed using MSV sequences from other African countries (retrieved from NCBI) alongside sequences obtained in this study. The analysis was conducted using MEGA X version 10.05 software. The results showed that the main symptoms observed in the field included the presence of longitudinal light green streaks on leaves, stunted plant growth, and incomplete seed development in infected plants. Phylogenetic analysis of the sequences from Côte d’Ivoire revealed three monophyletic groups, with sequences of some isolates collected from the same plot belonging to different groups. The MSV sequences from Côte d’Ivoire are very close to those from Rwanda. This study underscores the need for further investigation into the genetic diversity of MSV strains to enhance the diagnosis and management of this viral disease, which is particularly prevalent in maize crops in Côte d’Ivoire.
基金Princess Nourah bint Abdulrahman University Research Supporting Project Number PNURSP2025R241,Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.
文摘Nitrogen (N) is a crucial nutrient vital for the growth and productivity of maize. However, excessive nitrogen application can result in numerous environmental and ecological problems, such as water pollution, biodiversity loss, and greenhouse gas emissions. Therefore, breeding maize hybrids resilient to low nitrogen conditions is crucial for sustainable agriculture, especially under low nitrogen conditions. Consequently, this study aimed to evaluate the combining ability and heterosis of maize lines, recognize promising hybrids, and study gene action controlling key traits under low and recommended N stress conditions. The half-diallel mating design hybridized seven maize inbreds, resulting in 21 F1 hybrids. These hybrids, along with two high-yielding commercial hybrids (SC10 and TWC310), were evaluated in field trials under recommended (290 kg/ha) and low N (166 kg N/ha) conditions. Significant variations were observed among assessed hybrids for all measured traits, with non-additive gene action being predominant for grain yield and its related characteristics under recommended and low N conditions. Inbred lines P105 and P106 were recognized as effective combiners for earliness, with P105 also excelling in shorter plant height and lower ear placement. In addition, P101, P102, and P104 were identified as good combiners for increasing grain yield and related attributes under low N conditions. The crosses P105 × P106 and P106 × P107 demonstrated outstanding heterotic effects for earliness, while hybrids P101 × P102 and P102 × P104 exhibited remarkable heterotic effects for grain yield low nitrogen stress conditions. These promising hybrids could be considered for commercial use after further evaluation. Strong positive correlations were found between grain yield and ear height, plant height, number of kernels per row, and 1000-grain weight, highlighting their importance for indirect selection to enhance the grain yield of maize under low N stress conditions.
基金supported by the National Key Research and Development Program of China(2022YFD190160304 and 2018YFD0301206)Natural Science Foundation of Sichuan Province(2022NSFSC0013)Sichuan Provincial Maize Innovation Team Construction Project(SCCXTD-2023-02).
文摘A four-year field experiment was conducted with two cultivars and four N rate to investigate the spatiotemporal characteristics of leaf senescence in maize after silking and its response to N fertilizer rates on them,as well as to reveal the differences in post-silking chlorophyll degradation between low-N-tolerant cultivars.The results showed that the order of leaf senescence after silking in maize was lower leaf>upper leaf>ear leaf,leaf tip>middle>base.Increasing N fertilizer down-regulated the expression of ZmCLH2 and ZmPPH in the leaves at 10-30 d after silking,reducing CLH and PPH activities,thereby delaying the leaf senescence.These effects were more prominent in low-N-sensitive cultivar Xianyu 508(XY508)than in low-N-tolerant cultivar Zhenghong 311(ZH311),especially in the lower leaves and leaf tip.Under low N condition,leaf yellowing and chlorophyll degradation occurred later and slower in ZH311 than in XY508.This resulted in a higher post-silking dry matter accumulation and grain yield in ZH311,which may be one of the important physiological bases of low nitrogen tolerant cultivars.Future research should focus on developing low-N-tolerant maize cultivars with slower leaf senescence near the ear after silking.
基金supported by the National Natural Science Foundation of China(32172118)the National Key Research and Development Program of China(2016YFD0300110 and 2016YFD0300101)+1 种基金the Basic Scientific Research Fund of Chinese Academy of Agricultural Sciences,China(S2022ZD05)the Agricultural Science and Technology Innovation Program,China(CAAS-ZDRW202004)。
文摘The distributions of light and nitrogen within a plant's canopy reflect the growth adaptation of crops to the environment and are conducive to improving the carbon assimilation ability.So can the yield in crop production be maximized by improving the light and nitrogen distributions without adding any additional inputs?In this study,the effects of different nitrogen application rates and planting densities on the canopy light and nitrogen distributions of two highyielding maize cultivars(XY335 and DH618)and the regulatory effects of canopy physiological characteristics on radiation use efficiency(RUE)and yield were studied based on high-yield field experiments in Qitai,Xinjiang Uygur Autonomous Region,China,during 2019 and 2020.The results showed that the distribution of photosynthetically active photon flux density(PPFD)in the maize canopy decreased from top to bottom,while the vertical distribution of specific leaf nitrogen(SLN)initially increased and then decreased from top to bottom in the canopy.When SLN began to decrease,the PPDF values of XY335 and DH618 were 0.5 and 0.3,respectively,corresponding to 40.6 and49.3%of the total leaf area index(LAI).Nitrogen extinction coefficient(K_(N))/light extinction coefficient(K_(L))ratio in the middle and lower canopy of XY335(0.32)was 0.08 higher than that of DH618(0.24).The yield and RUE of XY335(17.2 t ha^(-1)and 1.8g MJ^(-1))were 7.0%(1.1 t ha^(-1))and 13.7%(0.2 g MJ^(-1))higher than those of DH618(16.1 t ha^(-1)and 1.6 g MJ^(-1)).Therefore,better light conditions(where the proportion of LAI in the upper and middle canopy was small)improved the light distribution when SLN started to decline,thus helping to mobilize the nitrogen distribution and maintain a high K_(N)and K_(N)/K_(L)ratio.In addition,K_(N)/K_(L)was a key parameter for yield improvement when the maize nutrient requirements were met at 360 kg N ha^(-1).At this level,an appropriately optimized high planting density could promote nitrogen utilization and produce higher yields and greater efficiency.The results of this study will be important for achieving high maize yields and the high efficiency cultivation and breeding of maize in the future.
文摘In view of the problems that the drilling depth can not be adjusted and the amount of liquid injection can not be accurately modulated in the local test device of maize variety breeding and disease resistance,combining the test technical requirements of drilling,liquid injection and sealing of the penultimate radial pitch of maize straw from the ground,a quantitative adjustable liquid injection device for maize stalk center borehole was designed.Its structure,working principle,key technical parameters and practical application effect were elaborated in detail.The field experiment demonstrated that the quantitative adjustable liquid injection device for maize stalk center borehole could meet the requirements of the local test of maize stalk rot.
基金funded by the National Natural Science Program of China(2022YFD1900300)the China Scholarship Council(CSC)through the CSC-CSIRO(Commonwealth Scientific and Industrial Research Organisation)Joint Ph D Program,the Zhumadian Major Scientific and Technological Innovation Project,China(170109564016)the Huanghuai University Scientific Research Foundation,China(502310020017)。
文摘We used field experimental data to evaluate the ability of the agricultural production system model (APSIM) to simulate soil P availability,maize biomass and grain yield in response to P fertilizer applications on a fluvo-aquic soil in the North China Plain.Crop and soil data from a 2-year experiment with three P fertilizer application rates(0,75 and 300 kg P_(2)O_(5) ha^(–1)) were used to calibrate the model.Sensitivity analysis was carried out to investigate the influence of APSIM SoilP parameters on the simulated P availability in soil and maize growth.Crop and soil P parameters were then derived by matching or relating the simulation results to observed crop biomass,yield,P uptake and Olsen-P in soil.The re-parameterized model was further validated against 2 years of independent data at the same sites.The re-parameterized model enabled good simulation of the maize leaf area index (LAI),biomass,grain yield,P uptake,and grain P content in response to different levels of P additions against both the calibration and validation datasets.Our results showed that APSIM needs to be re-parameterized for simulation of maize LAI dynamics through modification of leaf size curve and a reduction in the rate of leaf senescence for modern staygreen maize cultivars in China.The P concentration limits (maximum and minimum P concentrations in organs)at different stages also need to be adjusted.Our results further showed a curvilinear relationship between the measured Olsen-P concentration and simulated labile P content,which could facilitate the initialization of APSIM P pools in the NCP with Olsen-P measurements in future studies.It remains difficult to parameterize the APSIM SoilP module due to the conceptual nature of the pools and simplified conceptualization of key P transformation processes.A fundamental understanding still needs to be developed for modelling and predicting the fate of applied P fertilizers in soils with contrasting physical and chemical characteristics.
基金supported by Princess Nourah bint Abdulrahman University Researchers Supporting Project number(PNURSP2024R318)Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.The authors extend their appreciation to the Deanship of Research and Graduate Studies at King Khalid University for funding this work through Large Research Project under grant number RGP2/342/45supported by the Deanship of Scientific Research,Vice Presidency for Graduate Studies and Scientific Research,King Faisal University,Saudi Arabia(KFU241870).
文摘Developing high-yield maize hybrids is critical for sustaining maize production,especially in the face of rapid climate changes and the growing global population.Exploring the genetic diversity and combining ability in parental inbreds is needed for developing such high-yielding hybrids.Consequently,this study aimed at evaluating parental genetic diversity employing simple sequence repeats(SSR)markers,estimating effects of general(GCA)and specific(SCA)combining abilities for grain yield and yield contributing characters,identifying high yielding hybrids,and evaluating the association of SCA effects and performance of hybrids with genetic distance.Half-diallel mating scheme was utilized to develop 21 F_(1) hybrids from seven diverse maize inbred lines.The F_(1) hybrids along with check hybrid(SC-10),were investigated in a field trial over two growing seasons under arid conditions.The assessed F_(1) hybrids displayed significant genetic variations across all recorded traits.The inbreds P_(1) and P_(3) were detected as effective combiners to develop early maturing hybrids.Additionally,P_(3) and P_(4) were recognized as better combiners for improving grain yield and yield attributed characters.The hybrids P_(1)×P_(5) and P_(4)×P_(7) displayed significant SCA effects coupled with favorable agronomic performance.These hybrids are recommended for further evaluation and release as variety for arid environments to increase total maize production and contribute to food security.The alleles per locus differed between 2 and 5,with average of 3.5 alleles/locus.The polymorphic information content(PIC)altered between 0.21 to 0.74,with a mean of 0.56.Unweighted neighbor-joining tree grouped the inbred lines into three clusters,providing a valuable tool to decrease the crosses needed to be assessed in the trial field.Parental genetic distance varied from 0.63 to 0.90,averaging 0.79.The relationship between genetic diversity assessed through SSR markers and SCA effects was insignificant for all considered traits.Otherwise,SCA demonstrated a significant correlation with hybrid performance,suggesting that SCA serves as a reliable predictor for hybrid performance.The assessed maize inbred lines and developed hybrids revealed substantial genetic variability,offering valuable resources for enhancing maize productivity under arid conditions.The identified promising inbred lines(P_(1),P_(3),and P_(4))might be regarded as effective combiners for developing early-maturing genotypes and excellent combiners for enhancing yield attributes.Notably,the developed hybrids P_(1)×P_(5) and P_(4)×P_(7) possessed significant SCA alongside superior yield traits.SCA demonstrated a significant correlation with hybrid performance,suggesting its potential as a reliable predictor for the performance of developed hybrids.
基金financial support of the National Natural Science Foundation of China(U21A20218 and 32101857)the‘Double First-Class’Key Scientific Research Project of Education Department in Gansu Province,China(GSSYLXM-02)+1 种基金the Fuxi Young Talents Fund of Gansu Agricultural University,China(Gaufx03Y10)the“Innovation Star”Program of Graduate Students in 2023 of Gansu Province,China(2023CXZX681)。
文摘The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.However,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains unknown.This study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to 2021.The treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N supply.When water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme activities.Compared with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improved urease activity and nitrate reductase activity by 5.4% at the R2(blister)stage and 19.6% at the V6(6th leaf)stage,and increased net income and the benefit:cost ratio by 22.1 and 16.7%,respectively.W1N1D2 and W1N2D2 reduced the nitrate nitrogen and ammoniacal nitrogen contents at the R6 stage in the 40-100 cm soil layer,compared with W2N2D1.In summary,increasing the planting density by 30% can compensate for the loss of grain yield and aboveground N accumulation under reduced water and N inputs.Meanwhile,increasing the maize density by 30% improved grain yield and aboveground N accumulation when water was reduced by 20% while the N application rate remained constant in arid irrigation areas.
