Semidwarf breeding has boosted crop production and is a well-known outcome from the first Green Revolution. The Green Revolution gene Semidwarf 1(SD1), which modulates gibberellic acid(GA) biosynthesis, plays a princi...Semidwarf breeding has boosted crop production and is a well-known outcome from the first Green Revolution. The Green Revolution gene Semidwarf 1(SD1), which modulates gibberellic acid(GA) biosynthesis, plays a principal role in determining rice plant height. Mutations in SD1 reduce rice plant height and promote lodging resistance and fertilizer tolerance to increase grain production. The plant height mediated by SD1 also favors grain yield under certain conditions. However, it is not yet known whether the function of SD1 in upland rice promotes adaptation and grain production. In this study, the plant height and grain yield of irrigated and upland rice were comparatively analyzed under paddy and dryland conditions. In response to dryland environments, rice requires a reduction in plant height to cope with water deficits. Upland rice accessions had greater plant heights than their irrigated counterparts under both paddy and dryland conditions, and appropriately reducing plant height could improve adaptability to dryland environments and maintain high grain yield formation. Moreover, upland rice cultivars with thicker stem diameters had stronger lodging resistance, which addresses the lodging problem. Knockout of SD1 in the upland rice cultivar IRAT104 reduced the plant height and grain yield, demonstrating that the adjustment of plant height mediated by SD1 could increase grain production in dryland fields. In addition, an SD1 genetic diversity analysis verified that haplotype variation causes phenotypic variation in plant height. During the breeding history of rice, SD1 allelic mutations were selected from landraces to improve the grain yield of irrigated rice cultivars, and this selection was accompanied by a reduction in plant height. Thus, five known mutant alleles were analyzed to verify that functional SD1 is required for upland rice production. All these results suggest that SD1 might have undergone artificial positive selection in upland rice, which provides further insights concerning greater plant height in upland rice breeding.展开更多
Upland rice shows dryland adaptation in the form of a deeper and denser root system and greater drought resistance than its counterpart,irrigated rice.Our previous study revealed a difference in the frequency of the O...Upland rice shows dryland adaptation in the form of a deeper and denser root system and greater drought resistance than its counterpart,irrigated rice.Our previous study revealed a difference in the frequency of the OsNCED2 gene between upland and irrigated populations.A nonsynonymous mutation(C to T,from irrigated to upland rice)may have led to functional variation fixed by artificial selection,but the exact biological function in dryland adaptation is unclear.In this study,transgenic and association analysis indicated that the domesticated fixed mutation caused functional variation in OsNCED2,increasing ABA levels,root development,and drought tolerance in upland rice under dryland conditions.OsNCED2-overexpressing rice showed increased reactive oxygen species-scavenging abilities and transcription levels of many genes functioning in stress response and development that may regulate root development and drought tolerance.OsNCED2^(T)-NILs showed a denser root system and drought resistance,promoting the yield of rice under dryland conditions.OsNCED2^(T)may confer dryland adaptation in upland rice and may find use in breeding dryland-adapted,water-saving rice.展开更多
Background Cotton fiber is a model tissue for studying microtubule-associated proteins(MAPs).The Xklp2(TPX2)proteins that belong to the novel MAPs member mainly participate in the formation and development of microtub...Background Cotton fiber is a model tissue for studying microtubule-associated proteins(MAPs).The Xklp2(TPX2)proteins that belong to the novel MAPs member mainly participate in the formation and development of microtubule(MT).However,there is a lack of studies concerning the systematic characterization of the TPX2 genes family in cotton.Therefore,the identification and portrayal of G.hirsutum TPX2 genes can provide key targets for molecular manipula-tion in the breeding of cotton fiber improvement.Result In this study,TPX2 family genes were classified into two distinct subclasses TPXLs and MAP genes WAVE DAMP-ENED2-LIKE(WDLs)and quite conservative in quantity.GhWDL3 was significantly up-regulated in 15 days post anthe-sis fibers of ZRI-015(an upland cotton with longer and stronger fiber).GhWDL3 promotes all stem hairs to become straight when overexpressed in Arabidopsis,which may indirectly regulate cotton fiber cell morphology during fiber development.Virus induced gene silencing(VIGS)results showed that GhWDL3 inhibited fiber cell elongation at fiber development periods through regulating the expression of cell wall related genes.Conclusion These results reveal that GhWDL3 regulated cotton fiber cell elongation and provide crucial information for the further investigation in the regulatory mechanisms/networks of cotton fiber length.展开更多
Background High temperature stress at peak flowering stage of cotton is a major hindrance for crop potential.This study aimed to increase genetic divergence regarding heat tolerance in newly developed cultivars and hy...Background High temperature stress at peak flowering stage of cotton is a major hindrance for crop potential.This study aimed to increase genetic divergence regarding heat tolerance in newly developed cultivars and hybrids.Fifty cotton genotypes and 40 F1(hybrids)were tested under field conditions following the treatments,viz.,high temperature stress and control at peak flowering stage in August and October under April and June sowing,respectively.Results The mean squares revealed significant differences among genotypes,treatments,genotype×treatment for relative cell injury,chlorophyll contents,canopy temperature,boll retention and seed cotton yield per plant.The genetic diversity among 50 genotypes was analyzed through cluster analysis and heat susceptibility index(HSI).The heat tolerant genotypes including FH-Noor,NIAB-545,FH-466,FH-Lalazar,FH-458,NIAB-878,IR-NIBGE-8,Weal-AGShahkar,and heat sensitive,i.e.,CIM-602,Silky-3,FH-326,SLH-12 and FH-442 were hybridized in line×tester fashion to produce F1 populations.The breeding materials’populations(40 F1)revealed higher specific combining ability variances along with dominance variances,decided the non-additive type gene action for all the traits.The best general combining ability effects for most of the traits were displayed by the lines,i.e.,FH-Lalazar,NIAB-878 along with testers FH-326 and Silky-3.Specific combining ability effects and better-parent heterosis were showed by the crosses,viz.,FH-Lalazar×Silky-3,FH-Lalazar×FH-326,NIAB-878×Silky-3,and NIAB-878×FH-326 for seed cotton yield and yield contributing traits under high temperature stress.Conclusion Heterosis breeding should be carried out in the presence of non-additive type gene action for all the studied traits.The best combiner parents with better-parent heterosis may be used in crossing program to develop high yielding cultivars,and hybrids for high temperature stress tolerance.展开更多
Lignin metabolism plays a pivotal role in plant defense against pathogens and is always positively correlated as a response to pathogen infection. Thus, understanding resistance genes against plant pathogens depends o...Lignin metabolism plays a pivotal role in plant defense against pathogens and is always positively correlated as a response to pathogen infection. Thus, understanding resistance genes against plant pathogens depends on a genetic analysis of the lignin response. This study used eight Upland cotton lines to construct a multi-parent advanced generation intercross(MAGIC) population(n=280), which exhibited peculiar characteristics from the convergence of various alleles coding for advantageous traits. In order to measure the lignin response to Verticillium wilt(LRVW), the artificial disease nursery(ADN) and rotation nursery(RN) were prepared for MAGIC population planting in four environments. The stem lignin contents were collected, and the LRVW was measured with the lignin value of ADN/RN in each environment, which showed significant variations. We employed 9 323 high-quality single-nucleotide polymorphism(SNP) markers obtained from the Cotton-SNP63K array for genotyping the MAGIC population. The SNPs were distributed through the whole genome with 4.78 SNP/Mb density, ranging from 1.14(ChrA06) to 10.08(ChrD08). In addition, a genome-wide association study was performed using a Mixed Linear Model(MLM) for LRVW. Three stable quantitative trait loci(QTLs), qLRVW-A04, qLRVW-A10, and qLRVW-D05, were identified in more than two environments. Two key candidate genes, Ghi_D05G01046 and Ghi_D05G01221, were selected within the QTLs through the combination of variations in the coding sequence, induced expression patterns, and function annotations. Both genes presented nonsynonymous mutations in coding regions and were strongly induced by Verticillium dahliae. Ghi_D05G01046 encodes a leucine-rich extensin(LRx) protein involved in Arabidopsis cell wall biosynthesis and organization. Ghi_D05G01221 encodes a transcriptional co-repressor novel interactor of novel interactor of jasmonic acid ZIM-domain(JAZ–NINJA), which functions in the jasmonic acid(JA) signaling pathway. In summary, the study creates valuable genetic resources for breeding and QTL mapping and opens up a new perspective to uncover the genetic basis of VW resistance in Upland cotton.展开更多
The upland agricultural soils in North China are distributed north of a line between the Kunlun Mountains, the Qinling Mountains and the Huaihe River. They occur in arid, semi-arid and semi-humid regions and crop prod...The upland agricultural soils in North China are distributed north of a line between the Kunlun Mountains, the Qinling Mountains and the Huaihe River. They occur in arid, semi-arid and semi-humid regions and crop production often depends on rain-fed or irrigation to supplement rainfall. This paper summarizes the characteristics of gross nitrogen(N) transformation, the fate of N fertilizer and soil N as well as the N loss pathway, and makes suggestions for proper N management in the region. The soils of the region are characterized by strong N mineralization and nitrification, and weak immobilization and denitrification ability, which lead to the production and accumulation of nitrate in the soil profile. Large amounts of accumulated nitrate have been observed in the vadose-zone in soils due to excess N fertilization in the past three decades, and this nitrate is subject to occasional leaching which leads to groundwater nitrate contamination. Under farmer's conventional high N fertilization practice in the winter wheat-summer maize rotation system(N application rate was approximately 600 kg ha–1 yr–1), crop N uptake, soil residual N, NH_3 volatilization, NO_3~– leaching, and denitrification loss accounted for around 27, 30, 23, 18 and 2% of the applied fertilizer N, respectively. NH_3 volatilization and NO_3~– leaching were the most important N loss pathways while soil residual N was an important fate of N fertilizer for replenishing soil N depletion from crop production. The upland agricultural soils in North China are a large source of N_2O and total emissions in this region make up a large proportion(approximately 54%) of Chinese cropland N_2O emissions. The "non-coupled strong ammonia oxidation" process is an important mechanism of N_2O production. Slowing down ammonia oxidation after ammonium-N fertilizer or urea application and avoiding transient high soil NH4+ concentrations are key measures for reducing N_2O emissions in this region. Further N management should aim to minimize N losses from crop and livestock production, and increase the recycling of manure and straw back to cropland. We also recommend adoption of the 4 R(Right soure, Right rate, Right time, Right place) fertilization techniques to realize proper N fertilizer management, and improving application methods or modifying fertilizer types to reduce NH_3 volatilization, improving water management to reduce NO_3~– leaching, and controlling the strong ammonia oxidation process to abate N_2O emission. Future research should focus on the study of the trade-off effects among different N loss pathways under different N application methods or fertilizer products.展开更多
To evaluate the effects of various rotation systems on rice grain yield and N use efficiency, a paddy–upland cropping experiment(2013–2016) was conducted in southeastern China. The experiment was designed using six ...To evaluate the effects of various rotation systems on rice grain yield and N use efficiency, a paddy–upland cropping experiment(2013–2016) was conducted in southeastern China. The experiment was designed using six different rice––winter crop rotations: rice–fallow(RF),rice–wheat(RW), rice–potato with rice straw mulch(RP), rice–green manure(Chinese milk vetch; RC–G), rice–oilseed rape(RO), and rice–green manure crop(oilseed rape with fresh straw incorporated into soil at flowering; RO–G) and three N rates, N0(0 kg N ha-1), N1(142.5 kg N ha-1), and N2(202.5 kg N ha-1). Average rice yields in the RF(5.93 t ha-1) rotation were significantly lower than those in the rotations with winter crops(7.20–7.48 t ha-1)under the N0 treatment, suggesting that incorporation of straw might be more effective for increasing soil N than winter fallow. The rice yield differences among the rotations varied by year with the N input. In general, the grain yields in the RP and RO–G rotations –were respectively 11.6–28.5% and 14.80–37.19% higher than those in the RF in plots with N applied. Increasing the N rate may have tended to minimize the average yield gap between the RF and the other rotations; the yield gaps were 18.55%, 4.14%, and 0.23% in N0, N1, and N2, respectively. However, the N recovery efficiency in the RF was significantly lower than that in other rotations, except for 2015 under both N1 and N2 rates, a finding that implies a large amount of chemical N loss. No significant differences in nitrogen agronomic efficiency(NAE) and physiological efficiency(NPE) were found between the rotations with legume(RC–G) and non–legume(RO and RW) winter crops, a result that may be due partly to straw incorporation. For this reason, we concluded that the return of straw could reduce differences in N use efficiency between rotations with and without legume crops. The degree of synchrony between the crop N demand and the N supply was evaluated by comparison of nitrogen balance degree(NBD) values. The NBD values in the RP and RW were significantly lower than those in the other rotations under both N1 and N2 rates. Thus,in view of the higher grain yield in the RP compared to the RW under the N1 rate, the RP rotation might be a promising practice with comparable grain yield and greater N use efficiency under reduced N input relative to the other rotations. The primary yield components of the RF and RP were identified as number of panicles m-2 and numbers of kernels panicle-1, respectively. The NAE and NPE were positively correlated with harvest index, possibly providing a useful indicator for evaluating N use efficiency.展开更多
Worldwide, approximately 27 million ha of rice are grown in upland rather than paddy fields, and is subject to drought stress. To counter this stress, it is desirable to breed new rice cultivars with improved drought ...Worldwide, approximately 27 million ha of rice are grown in upland rather than paddy fields, and is subject to drought stress. To counter this stress, it is desirable to breed new rice cultivars with improved drought tolerance. For breeding purposes, especially for breeding upland rice, it is desirable to develop a simple and accurate method to evaluate rice drought tolerance. We describe a new method that can be used to evaluate efficiently the drought tolerance degree(DTD) of upland rice cultivars, and call it the DTD method.DTD is defined as the mean of the ratios of green leaf length to total leaf length of the top three leaves in every rice seedling after drought treatment, and thus takes values from zero to one. To test whether the DTD method works effectively to evaluate drought tolerance of upland rice cultivars, we determined the DTD values of 13 upland rice cultivars showing varying degrees of drought tolerance in drought-tolerance trials. The idrl-1 mutant, which displayed the strongest drought tolerance of the 13 cultivars as identified by drought-tolerance trials under severe drought stress, had the highest DTD value and297-28, displaying the weakest drought tolerance, had the lowest DTD value. Further analyses of water potential, survival rate, panicles per plant, spikelets per panicle, seed setting rate, yield per plant, and contents of proline, chlorophyll, and malondialdehyde(MDA) indicated that DTD values are in general correlated with the values of these traits,making this new method useful for assessing the drought tolerance of upland rice cultivars.These results show that the DTD method is a simple, direct and relatively accurate evaluation method for drought-tolerance breeding of upland rice.展开更多
It is of great significance to study the root characteristics of rice to improve water and nitrogen(N) use efficiency and reduce environmental pollution. This study investigated whether root traits and architecture of...It is of great significance to study the root characteristics of rice to improve water and nitrogen(N) use efficiency and reduce environmental pollution. This study investigated whether root traits and architecture of rice influence grain yield, as well as water and N utilization efficiency. An experiment was conducted using the upland rice cultivar Zhonghan 3(a japonica cultivar) and paddy rice cultivar Huaidao 5(also a japonica cultivar) using three N levels, namely, 2 g urea/pot(low amount, LN), 3 g urea/pot(normal amount, NN), and 4 g urea/pot(high amount, HN), and three soil water potentials(SWPs, namely, well-watered(0 kPa), mildly dried(–20 kPa) and severely dried(–40 kPa). The results showed that with decreasing SWP, the percentage of upland rice roots increased in the 0–5 cm tillage layer, and decreased in the 5–10 and 10–20 cm tillage layers, whereas paddy rice roots showed the opposite trend. With increasing amounts of N, the yield of upland and paddy rice increased, and the percentage of root volume ratios of the two rice cultivars in the 0–5 and 5–10 cm tillage layers increased, whereas that in the 10–20 cm tillage layer decreased. The roots of upland rice are mainly distributed in the 10–20 cm tillage layer, whereas most paddy rice roots are in the 0–5 cm tillage layer. These results indicate that the combination of-20 kPa SWP and NN in upland rice and 0 kPa SWP and LN in paddy rice promotes the growth of the root system during the middle and late stages, which in turn may decrease the requirements for water and N fertilizer and increase rice yield.展开更多
The effects of mulching mode on population physiology and ecology of rice were studied using a combination P88S/1128 as the material under three mulching cultivation modes including plastic film mulching, straw mulchi...The effects of mulching mode on population physiology and ecology of rice were studied using a combination P88S/1128 as the material under three mulching cultivation modes including plastic film mulching, straw mulching and liquid film mulching, as well as bare cultivation (control). The results indicated that mulching mode had significant effects on micro-meteorological factors and individual growth of rice, as shown by an increase of relative humidity, a better internal micro-meteorological environment of rice population, a significant reduction under the rice canopy temperature, especially during high-temperature periods. Rice plants under mulching cultivation conditions displayed a stronger transpiration and lower leaf temperature, thereby improving the ability of anti-high temperature stress and markedly increasing the photosynthetic rate. Furthermore, the yield components of rice were significantly optimized under mulching cultivation, of which with plastic film mulching displayed the highest grain number per panicle and seed-setting rate, and a yield increase of 16.81% compared with the control; and with straw mulching displayed an increase of effective panicle number and a 9.59% increase of total yield compared to the control.展开更多
To investigate the effects of long-term fertilization systems on soil microbial community structure,labile organic carbon and nitrogen and enzyme activity in yellow sand paddy field and upland,a field experiment was c...To investigate the effects of long-term fertilization systems on soil microbial community structure,labile organic carbon and nitrogen and enzyme activity in yellow sand paddy field and upland,a field experiment was conducted at the experimental station of Dongyang Institute of Maize Research in Zhejiang Province,China in 2009.The experiment consisted of six treatments with three replicates,and they were arranged in a completely randomized design,including no fertilization in paddy field (PCK),conventional fertilization in paddy field (PCF),formulated fertilization by soil testing in paddy field (PSTF),formulated fertilization by soil testing with organic manure in paddy field (PSTF+OF),conventional fertilization on upland (DCF),and formulated fertilization by soil testing with organic manure on upland (DSTF+OF).Soil nutrients,enzyme activity,microbial biomass and community structure were determined in 2015.The results showed that compared with no fertilization in paddy field (PCK),fertilization increased soil phosphorus and potassium content,and decreased pH value.No fertilization in paddy field (PCK) had no significant effect on soil culturable microorganisms in paddy field and upland,but formulated fertilization by soil testing with organic manure on upland (DSTF+OF) significantly increased the number of fungi.Formula fertilization by soil testing with organic manure (PSTF+OF) also significantly increased soil microbial biomass carbon and nitrogen in paddy field and upland.Moreover,fertilization had no significant effect on soil cellulase activity,but formula fertilization by soil testing with organic manure (PSTF+OF) significantly increased soil dehydrogenase and catalase activity.Therefore,long-term application of chemical fertilizer with organic fertilizer can effectively improve soil fertility.展开更多
Allene oxide cyclase(AOC, E 5.3.99.6) is an essential enzyme in the jasmonic acid(JA)biosynthetic pathway and mediates a wide range of adaptive responses. In this report, five AOC genes(Gh AOC1–Gh AOC5) were cloned f...Allene oxide cyclase(AOC, E 5.3.99.6) is an essential enzyme in the jasmonic acid(JA)biosynthetic pathway and mediates a wide range of adaptive responses. In this report, five AOC genes(Gh AOC1–Gh AOC5) were cloned from upland cotton(Gossypium hirsutum L.),sequenced, and characterized. Real-time PCR analysis indicated that the transcripts of Gh AOCs were abundantly expressed in roots and less in fibers, and regulated in cotton plants under methyl jasmonate(Me JA) and Cu Cl2 stresses. To investigate the role of Gh AOC under copper stress, transgenic Arabidopsis plants overexpressing cotton Gh AOC1 under control of the Cauliflower mosaic virus 35S(Ca MV 35S) promoter were generated. Compared to untransformed plants, Gh AOC1-overexpressing Arabidopsis thaliana plants exhibited markedly higher survival rate, shoot fresh weight, shoot dry weight, and photosynthetic efficiency, and reduced cell membrane damage and lipid peroxidation under copper stress.This study provides the first evidence that Gh AOC1 plays an important role in copper stress tolerance.展开更多
A total of 17 simple sequence repeat(SSR) markers linked to QTLs(qDTYs) governing grain yield under reproductive stage(RS) drought stress were used to assess the genetic relationship and prospecting new donors for q D...A total of 17 simple sequence repeat(SSR) markers linked to QTLs(qDTYs) governing grain yield under reproductive stage(RS) drought stress were used to assess the genetic relationship and prospecting new donors for q DTYs among 32 popular upland rice genotypes. These SSR markers generated a total of 36 alleles with an average allele count of 2.1 per locus. Polymorphic information content value of the markers ranged from 0.376 to 0.662 with an average value of 0.484. The expected heterozyogosity ranged from 0.381 to 0.632. STRUCTURE analysis divided the 32 genotypes into three sub-populations. Subsequent phenotyping revealed that all the tolerant genotypes were grouped into one sub-population, whereas the moderately tolerant and susceptible genotypes were grouped into separate sub-populations. Phylogenetic tree constructed by the unweighted neighbour-joining method also divided the genotypes into three clusters. The grouping pattern of genotypes into the clusters was similar to that into the STRUCTURE analysis, on the basis of drought tolerance level. The average value of genetic dissimilarity coefficient among the genotypes was observed to be 0.486. Furthermore, by combining genotyping data with phenotyping data, 16 new donors for 6 qDTYs were identified.展开更多
With increasing demand for high-quality cotton,it is desirable to identify genes involved in fiber development for molecular improvement of cotton.In this study,780 differentially expressed genes(DEGs)were identified ...With increasing demand for high-quality cotton,it is desirable to identify genes involved in fiber development for molecular improvement of cotton.In this study,780 differentially expressed genes(DEGs)were identified in developing fibers at 10 days post-anthesis(DPA)in Gossypium hirsutum acc.DH962 and G.hirsutum cv.Jimian 5 using RNA-seq.Of 15 stable QTL for fiber quality identified in the same two parents in previous studies,4,3,6,1,and 1 QTL were associated with fiber length(FL),fiber strength(FS),micronaire(MIC),fiber elongation(FE)and fiber length uniformity ratio(FU),respectively.Integration of DEGs and QTL allowed the identification of 31 genes in 9 QTL regions,of which 25 were highly expressed in fibers based on the transcriptome datasets and 9 were preferentially expressed in different stages of fiber development.Gh_A01G0453(GhDTX19),Gh_D07G1581 and Gh_D04G0942 were expressed specifically in 5 and 10 DPA fibers,with Gh_D04G0942 showing low expression in other tissues except pistil.Gh_D07G1799(GhGAUT9),Gh_D11G0326(GhVPS29),Gh_D11G0333(GhTCP14),and Gh_D11G0334(GhNRP2)were preferentially expressed in 5 or 10 DPA fibers;Gh_A01G0397(GhABCG10)and Gh_D07G1744 were expressed specifically in 20 and 25 DPA fibers.These results suggest candidate genes for molecular improvement of cotton fiber quality.展开更多
Somatic embryogenesis in upland cotton isstrongly genotype-dependent,which is a troublein cotton genetic engineering.Cloning genesrelated to somatic embryogenesis and thenintroducing the gene into mainly cultivatedvar...Somatic embryogenesis in upland cotton isstrongly genotype-dependent,which is a troublein cotton genetic engineering.Cloning genesrelated to somatic embryogenesis and thenintroducing the gene into mainly cultivatedvarieties would be greatly helpful for cottonimprovement by gene transfer.To study展开更多
Luang Prabang Province is located within the area recognized as the center of rice(Oryza sativa L.) diversity in Lao PDR. This study reported on grain quality characteristics of 60 upland rice seed samples sharing 49 ...Luang Prabang Province is located within the area recognized as the center of rice(Oryza sativa L.) diversity in Lao PDR. This study reported on grain quality characteristics of 60 upland rice seed samples sharing 49 variety names collected from 6 villages in Luang Prabang in 2015. Most of the samples has non-pigmented pericarp, while red pericarp was found in four samples and purple in five samples. Almost all of the samples were of large grain type, with glutinous endosperm in 70% and non-glutinous endosperm in 30%. The brown(unpolished) rice was found with a wide range of grain nutritional quality, including protein(9.2% ± 0.9%), Fe(15.9 ± 6.9 mg/kg), Zn(19.6 ± 2.1 mg/kg), anthocyanin(0.774 ± 0.880 mg/g), and anti-oxidative capacity(2.071 ± 1.373 mg/g). The varieties sharing similar names had similar morphological characteristics but varied in nutritional concentration, with required confirmation in genetic variation analysis. This study found that some rice varieties with high grain quality may benefit the farmers directly or could be used in varietal improvement programs.展开更多
A glutathione S-transferase gene (gst) has been introduced into restorers of cytoplasmic male sterility in upland cotton ( Gossypium hirsutum L. ) using Agrobacterium-mediated transformation. A transviable pollens of ...A glutathione S-transferase gene (gst) has been introduced into restorers of cytoplasmic male sterility in upland cotton ( Gossypium hirsutum L. ) using Agrobacterium-mediated transformation. A transviable pollens of hybrid (sterile line×restorer) F1. The hybrid gave 3.6 more bolls per plant, 10.1% less aborted seeds and 10.6% more lint yield when ‘Zheda strong restorer’ was used as male parent than when ‘DES-HAF277’ was. Southern and Northern bloting analysis showed that the foreign gst gene was detectable and highly expressed in ‘Zheda strong restorer’.展开更多
A field study was conducted to investigate the effects of leguminous crop cultivation on nitrousoxide (N2O) emissions from upland agricultural soils. Results demonstrated that N2O emission sequences were tively. While...A field study was conducted to investigate the effects of leguminous crop cultivation on nitrousoxide (N2O) emissions from upland agricultural soils. Results demonstrated that N2O emission sequences were tively. While in terms of seasonal emission, the sequence was that soybean ＞ peanut crop ＞ upland rice, being 0.77, 0.70 and 0.55 kg/ha respectively. Results also demonstrated that legume crop treatment emitted much more N2O than non-legume upland rice treatment and that N fertilized treatments emitted more than unand N fertilizer, therefore, were one of the important sources of N2O emissions from agricultural fields.展开更多
The planting of upland rice is one cropping option in area with limited water availability and low soil fertility in North and Northeast Thailand.The varietal selection was determined by grain yield potential,wide ada...The planting of upland rice is one cropping option in area with limited water availability and low soil fertility in North and Northeast Thailand.The varietal selection was determined by grain yield potential,wide adaptation,and good stability.This study was aimed at evaluation of indigenous upland rice germplasm for yield and yield stability in multi-locations.Thirty-six upland rice genotypes collected from six provinces of the North and Northeast Thailand and one check variety(Sewmaejan) were assessed under five locations in the rainy seasons of 2009 and 2010.The experiment was laid out in a randomized complete block design with three replications.The genotype grain yield was highly affected by location(59.90%),followed by genotypes(G)×location(L) interaction(12.80%) and genotype(6.79%).The most suitable location for the genotype evaluation was L3(Khon Kaen-KKU10) which associated with stability of grain yield for all genotypes.Furthermore,biplot and regression analysis indicated that genotype numbers 6(Jaowmong 1),10(Neawmong 1),18(Neawdum 1),19(Leamna),20(Prayaleamkang),32(Kunwang 2),and 33(Kunwang 3) showed great yield stability over five locations.The genotypes will be applicant for upland rice production area and parental base in breeding program.展开更多
Background:The utilization of heterosis has greatly improved the productivity of cotton worldwide.However,a major constraint for the large-scale promotion of F_(1) hybrid cotton is artificial emasculation and pollinat...Background:The utilization of heterosis has greatly improved the productivity of cotton worldwide.However,a major constraint for the large-scale promotion of F_(1) hybrid cotton is artificial emasculation and pollination.This study proposed the potential utilization of F_(2) hybrids to improve upland cotton production through a comparative evaluation of hybrid generations.Results:Eight upland cotton varieties were analyzed and crosses were made according to NCII incomplete diallel cross-breeding design in two cotton belts of China.Variance analysis revealed significant differences in agronomic,yield,and fiber quality in both generations and environments.The broad-sense heritability of agronomic and yield traits was relatively higher than quality traits.Furthermore,the narrow-sense heritability of some traits was higher in F_(2) than in the F_(1) generation in both cotton belts.Overall,parental lines Zhong901,ZB,L28,and Z98 were observed with maximum combining ability while combinations with strong special combining ability were ZB×DT,L28×Z98,and ZB×851.The yield traits heterosis was predominant in both generations.However,the level of heterosis was altered with trait,hybrid combination,generation,and environment.Interestingly,L28×Z98 performed outstandingly in Anyang.Its lint yield(LY)was 24.2%higher in F_(1) and 11.6%in F_(2) than that of the control Ruiza 816.The performance of SJ48×Z98 was excellent in Aral which showed 36.5%higher LY in F_(2)and 10.9%in F_(2)than control CCRI 49.Further results revealed most hybrid combinations had shown a low level of heterosis for agronomic and fiber quality traits in both generations.Comparatively,ZB×DT and L28×Z98 showed hybrid vigor for multiple traits in both generations and cotton belts.It is feasible to screen strong heterosis hybrid combinations with fine fiber in early generations.In the two environments,the correlation of some traits showed the same trend,and the correlation degree of Anyang site was higher than that of Aral site,and the correlation of some traits showed the opposite trend.According to the performance of strong heterosis hybrid combinations in different environments,the plant type,yield and fiber traits associated with them can be improved according to the correlation.Conclusions:Through comparative analysis of variance,combining ability,and heterosis in F_(2)and F_(2)hybrids in different cotton belts,this study proposed the potential utilization of F_(2)hybrids to improve upland cotton productivity in China.展开更多
基金supported by grants from the National Natural Science Foundation of China(32272079 and 32060474)the Yunnan Provincial Science and Technology Department,China(202101AS070001 and 202201BF070001-011)。
文摘Semidwarf breeding has boosted crop production and is a well-known outcome from the first Green Revolution. The Green Revolution gene Semidwarf 1(SD1), which modulates gibberellic acid(GA) biosynthesis, plays a principal role in determining rice plant height. Mutations in SD1 reduce rice plant height and promote lodging resistance and fertilizer tolerance to increase grain production. The plant height mediated by SD1 also favors grain yield under certain conditions. However, it is not yet known whether the function of SD1 in upland rice promotes adaptation and grain production. In this study, the plant height and grain yield of irrigated and upland rice were comparatively analyzed under paddy and dryland conditions. In response to dryland environments, rice requires a reduction in plant height to cope with water deficits. Upland rice accessions had greater plant heights than their irrigated counterparts under both paddy and dryland conditions, and appropriately reducing plant height could improve adaptability to dryland environments and maintain high grain yield formation. Moreover, upland rice cultivars with thicker stem diameters had stronger lodging resistance, which addresses the lodging problem. Knockout of SD1 in the upland rice cultivar IRAT104 reduced the plant height and grain yield, demonstrating that the adjustment of plant height mediated by SD1 could increase grain production in dryland fields. In addition, an SD1 genetic diversity analysis verified that haplotype variation causes phenotypic variation in plant height. During the breeding history of rice, SD1 allelic mutations were selected from landraces to improve the grain yield of irrigated rice cultivars, and this selection was accompanied by a reduction in plant height. Thus, five known mutant alleles were analyzed to verify that functional SD1 is required for upland rice production. All these results suggest that SD1 might have undergone artificial positive selection in upland rice, which provides further insights concerning greater plant height in upland rice breeding.
基金This work was supported by the National Natural Science Foundation of China(U1602266,32060474,and 31601274)grants from the Yunnan Provincial Science and Technology Department(202005AF150009 and 202101AS070001).
文摘Upland rice shows dryland adaptation in the form of a deeper and denser root system and greater drought resistance than its counterpart,irrigated rice.Our previous study revealed a difference in the frequency of the OsNCED2 gene between upland and irrigated populations.A nonsynonymous mutation(C to T,from irrigated to upland rice)may have led to functional variation fixed by artificial selection,but the exact biological function in dryland adaptation is unclear.In this study,transgenic and association analysis indicated that the domesticated fixed mutation caused functional variation in OsNCED2,increasing ABA levels,root development,and drought tolerance in upland rice under dryland conditions.OsNCED2-overexpressing rice showed increased reactive oxygen species-scavenging abilities and transcription levels of many genes functioning in stress response and development that may regulate root development and drought tolerance.OsNCED2^(T)-NILs showed a denser root system and drought resistance,promoting the yield of rice under dryland conditions.OsNCED2^(T)may confer dryland adaptation in upland rice and may find use in breeding dryland-adapted,water-saving rice.
基金supported by the National Key Research and Development Program of China(2022YFD1200300)China Agriculture Research System(CARS-15-01).
文摘Background Cotton fiber is a model tissue for studying microtubule-associated proteins(MAPs).The Xklp2(TPX2)proteins that belong to the novel MAPs member mainly participate in the formation and development of microtubule(MT).However,there is a lack of studies concerning the systematic characterization of the TPX2 genes family in cotton.Therefore,the identification and portrayal of G.hirsutum TPX2 genes can provide key targets for molecular manipula-tion in the breeding of cotton fiber improvement.Result In this study,TPX2 family genes were classified into two distinct subclasses TPXLs and MAP genes WAVE DAMP-ENED2-LIKE(WDLs)and quite conservative in quantity.GhWDL3 was significantly up-regulated in 15 days post anthe-sis fibers of ZRI-015(an upland cotton with longer and stronger fiber).GhWDL3 promotes all stem hairs to become straight when overexpressed in Arabidopsis,which may indirectly regulate cotton fiber cell morphology during fiber development.Virus induced gene silencing(VIGS)results showed that GhWDL3 inhibited fiber cell elongation at fiber development periods through regulating the expression of cell wall related genes.Conclusion These results reveal that GhWDL3 regulated cotton fiber cell elongation and provide crucial information for the further investigation in the regulatory mechanisms/networks of cotton fiber length.
基金Higher Education Commission of Pakistan for funding the experiments
文摘Background High temperature stress at peak flowering stage of cotton is a major hindrance for crop potential.This study aimed to increase genetic divergence regarding heat tolerance in newly developed cultivars and hybrids.Fifty cotton genotypes and 40 F1(hybrids)were tested under field conditions following the treatments,viz.,high temperature stress and control at peak flowering stage in August and October under April and June sowing,respectively.Results The mean squares revealed significant differences among genotypes,treatments,genotype×treatment for relative cell injury,chlorophyll contents,canopy temperature,boll retention and seed cotton yield per plant.The genetic diversity among 50 genotypes was analyzed through cluster analysis and heat susceptibility index(HSI).The heat tolerant genotypes including FH-Noor,NIAB-545,FH-466,FH-Lalazar,FH-458,NIAB-878,IR-NIBGE-8,Weal-AGShahkar,and heat sensitive,i.e.,CIM-602,Silky-3,FH-326,SLH-12 and FH-442 were hybridized in line×tester fashion to produce F1 populations.The breeding materials’populations(40 F1)revealed higher specific combining ability variances along with dominance variances,decided the non-additive type gene action for all the traits.The best general combining ability effects for most of the traits were displayed by the lines,i.e.,FH-Lalazar,NIAB-878 along with testers FH-326 and Silky-3.Specific combining ability effects and better-parent heterosis were showed by the crosses,viz.,FH-Lalazar×Silky-3,FH-Lalazar×FH-326,NIAB-878×Silky-3,and NIAB-878×FH-326 for seed cotton yield and yield contributing traits under high temperature stress.Conclusion Heterosis breeding should be carried out in the presence of non-additive type gene action for all the studied traits.The best combiner parents with better-parent heterosis may be used in crossing program to develop high yielding cultivars,and hybrids for high temperature stress tolerance.
基金financed by the National Natural Science Foundation of China (31760402 and 31771844)the Innovation Leadership Program in Sciences and Technologies for Young and Middle-aged Scientists of Xinjiang Production and Construction Corps, China (2019CB027)。
文摘Lignin metabolism plays a pivotal role in plant defense against pathogens and is always positively correlated as a response to pathogen infection. Thus, understanding resistance genes against plant pathogens depends on a genetic analysis of the lignin response. This study used eight Upland cotton lines to construct a multi-parent advanced generation intercross(MAGIC) population(n=280), which exhibited peculiar characteristics from the convergence of various alleles coding for advantageous traits. In order to measure the lignin response to Verticillium wilt(LRVW), the artificial disease nursery(ADN) and rotation nursery(RN) were prepared for MAGIC population planting in four environments. The stem lignin contents were collected, and the LRVW was measured with the lignin value of ADN/RN in each environment, which showed significant variations. We employed 9 323 high-quality single-nucleotide polymorphism(SNP) markers obtained from the Cotton-SNP63K array for genotyping the MAGIC population. The SNPs were distributed through the whole genome with 4.78 SNP/Mb density, ranging from 1.14(ChrA06) to 10.08(ChrD08). In addition, a genome-wide association study was performed using a Mixed Linear Model(MLM) for LRVW. Three stable quantitative trait loci(QTLs), qLRVW-A04, qLRVW-A10, and qLRVW-D05, were identified in more than two environments. Two key candidate genes, Ghi_D05G01046 and Ghi_D05G01221, were selected within the QTLs through the combination of variations in the coding sequence, induced expression patterns, and function annotations. Both genes presented nonsynonymous mutations in coding regions and were strongly induced by Verticillium dahliae. Ghi_D05G01046 encodes a leucine-rich extensin(LRx) protein involved in Arabidopsis cell wall biosynthesis and organization. Ghi_D05G01221 encodes a transcriptional co-repressor novel interactor of novel interactor of jasmonic acid ZIM-domain(JAZ–NINJA), which functions in the jasmonic acid(JA) signaling pathway. In summary, the study creates valuable genetic resources for breeding and QTL mapping and opens up a new perspective to uncover the genetic basis of VW resistance in Upland cotton.
基金supported by the National Natural Science Foundation of China (41471190)the National Key Research and Development Program of China (2016YFD0800102)+2 种基金the Special Fund for the Agricultural Public Welfare Profession of China (201503106)the Newton Fund, United Kingdom (BB/N013484/1)the GEF on the ‘Towards INMS’
文摘The upland agricultural soils in North China are distributed north of a line between the Kunlun Mountains, the Qinling Mountains and the Huaihe River. They occur in arid, semi-arid and semi-humid regions and crop production often depends on rain-fed or irrigation to supplement rainfall. This paper summarizes the characteristics of gross nitrogen(N) transformation, the fate of N fertilizer and soil N as well as the N loss pathway, and makes suggestions for proper N management in the region. The soils of the region are characterized by strong N mineralization and nitrification, and weak immobilization and denitrification ability, which lead to the production and accumulation of nitrate in the soil profile. Large amounts of accumulated nitrate have been observed in the vadose-zone in soils due to excess N fertilization in the past three decades, and this nitrate is subject to occasional leaching which leads to groundwater nitrate contamination. Under farmer's conventional high N fertilization practice in the winter wheat-summer maize rotation system(N application rate was approximately 600 kg ha–1 yr–1), crop N uptake, soil residual N, NH_3 volatilization, NO_3~– leaching, and denitrification loss accounted for around 27, 30, 23, 18 and 2% of the applied fertilizer N, respectively. NH_3 volatilization and NO_3~– leaching were the most important N loss pathways while soil residual N was an important fate of N fertilizer for replenishing soil N depletion from crop production. The upland agricultural soils in North China are a large source of N_2O and total emissions in this region make up a large proportion(approximately 54%) of Chinese cropland N_2O emissions. The "non-coupled strong ammonia oxidation" process is an important mechanism of N_2O production. Slowing down ammonia oxidation after ammonium-N fertilizer or urea application and avoiding transient high soil NH4+ concentrations are key measures for reducing N_2O emissions in this region. Further N management should aim to minimize N losses from crop and livestock production, and increase the recycling of manure and straw back to cropland. We also recommend adoption of the 4 R(Right soure, Right rate, Right time, Right place) fertilization techniques to realize proper N fertilizer management, and improving application methods or modifying fertilizer types to reduce NH_3 volatilization, improving water management to reduce NO_3~– leaching, and controlling the strong ammonia oxidation process to abate N_2O emission. Future research should focus on the study of the trade-off effects among different N loss pathways under different N application methods or fertilizer products.
基金The National Key Research and Development Program of China(2016YFD0300108,2016YFD0300208-02)the National Natural Science Foundation of China(31671638)+1 种基金the China Agriculture Research System(CARS-01-04A)the Special Fund for Agro-scientific Research in the Public Interest(201203096)partly supported this study
文摘To evaluate the effects of various rotation systems on rice grain yield and N use efficiency, a paddy–upland cropping experiment(2013–2016) was conducted in southeastern China. The experiment was designed using six different rice––winter crop rotations: rice–fallow(RF),rice–wheat(RW), rice–potato with rice straw mulch(RP), rice–green manure(Chinese milk vetch; RC–G), rice–oilseed rape(RO), and rice–green manure crop(oilseed rape with fresh straw incorporated into soil at flowering; RO–G) and three N rates, N0(0 kg N ha-1), N1(142.5 kg N ha-1), and N2(202.5 kg N ha-1). Average rice yields in the RF(5.93 t ha-1) rotation were significantly lower than those in the rotations with winter crops(7.20–7.48 t ha-1)under the N0 treatment, suggesting that incorporation of straw might be more effective for increasing soil N than winter fallow. The rice yield differences among the rotations varied by year with the N input. In general, the grain yields in the RP and RO–G rotations –were respectively 11.6–28.5% and 14.80–37.19% higher than those in the RF in plots with N applied. Increasing the N rate may have tended to minimize the average yield gap between the RF and the other rotations; the yield gaps were 18.55%, 4.14%, and 0.23% in N0, N1, and N2, respectively. However, the N recovery efficiency in the RF was significantly lower than that in other rotations, except for 2015 under both N1 and N2 rates, a finding that implies a large amount of chemical N loss. No significant differences in nitrogen agronomic efficiency(NAE) and physiological efficiency(NPE) were found between the rotations with legume(RC–G) and non–legume(RO and RW) winter crops, a result that may be due partly to straw incorporation. For this reason, we concluded that the return of straw could reduce differences in N use efficiency between rotations with and without legume crops. The degree of synchrony between the crop N demand and the N supply was evaluated by comparison of nitrogen balance degree(NBD) values. The NBD values in the RP and RW were significantly lower than those in the other rotations under both N1 and N2 rates. Thus,in view of the higher grain yield in the RP compared to the RW under the N1 rate, the RP rotation might be a promising practice with comparable grain yield and greater N use efficiency under reduced N input relative to the other rotations. The primary yield components of the RF and RP were identified as number of panicles m-2 and numbers of kernels panicle-1, respectively. The NAE and NPE were positively correlated with harvest index, possibly providing a useful indicator for evaluating N use efficiency.
基金supported by the National Key Research and Development Program of China(2016YFD0100600)the Fundamental Research Funds for the Central Universities (KYTZ201402, KYRC201409) to H.La
文摘Worldwide, approximately 27 million ha of rice are grown in upland rather than paddy fields, and is subject to drought stress. To counter this stress, it is desirable to breed new rice cultivars with improved drought tolerance. For breeding purposes, especially for breeding upland rice, it is desirable to develop a simple and accurate method to evaluate rice drought tolerance. We describe a new method that can be used to evaluate efficiently the drought tolerance degree(DTD) of upland rice cultivars, and call it the DTD method.DTD is defined as the mean of the ratios of green leaf length to total leaf length of the top three leaves in every rice seedling after drought treatment, and thus takes values from zero to one. To test whether the DTD method works effectively to evaluate drought tolerance of upland rice cultivars, we determined the DTD values of 13 upland rice cultivars showing varying degrees of drought tolerance in drought-tolerance trials. The idrl-1 mutant, which displayed the strongest drought tolerance of the 13 cultivars as identified by drought-tolerance trials under severe drought stress, had the highest DTD value and297-28, displaying the weakest drought tolerance, had the lowest DTD value. Further analyses of water potential, survival rate, panicles per plant, spikelets per panicle, seed setting rate, yield per plant, and contents of proline, chlorophyll, and malondialdehyde(MDA) indicated that DTD values are in general correlated with the values of these traits,making this new method useful for assessing the drought tolerance of upland rice cultivars.These results show that the DTD method is a simple, direct and relatively accurate evaluation method for drought-tolerance breeding of upland rice.
基金the National Natural Science Foundation of China(31671617)the National Key Research and Development Program of China(2016YFD0300502,2016YFD0300206 and 2018YFD0301306)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),China。
文摘It is of great significance to study the root characteristics of rice to improve water and nitrogen(N) use efficiency and reduce environmental pollution. This study investigated whether root traits and architecture of rice influence grain yield, as well as water and N utilization efficiency. An experiment was conducted using the upland rice cultivar Zhonghan 3(a japonica cultivar) and paddy rice cultivar Huaidao 5(also a japonica cultivar) using three N levels, namely, 2 g urea/pot(low amount, LN), 3 g urea/pot(normal amount, NN), and 4 g urea/pot(high amount, HN), and three soil water potentials(SWPs, namely, well-watered(0 kPa), mildly dried(–20 kPa) and severely dried(–40 kPa). The results showed that with decreasing SWP, the percentage of upland rice roots increased in the 0–5 cm tillage layer, and decreased in the 5–10 and 10–20 cm tillage layers, whereas paddy rice roots showed the opposite trend. With increasing amounts of N, the yield of upland and paddy rice increased, and the percentage of root volume ratios of the two rice cultivars in the 0–5 and 5–10 cm tillage layers increased, whereas that in the 10–20 cm tillage layer decreased. The roots of upland rice are mainly distributed in the 10–20 cm tillage layer, whereas most paddy rice roots are in the 0–5 cm tillage layer. These results indicate that the combination of-20 kPa SWP and NN in upland rice and 0 kPa SWP and LN in paddy rice promotes the growth of the root system during the middle and late stages, which in turn may decrease the requirements for water and N fertilizer and increase rice yield.
基金supported by the Major Science and Technology Capture Project in the Eleventh Five-Year Plan in Hunan Province, China titled 'Super high yielding hybrid rice cultivation technology research and demonstration'the National Great Science and Technology Support Plan, Chinathe National Science and Technology Project for Food Production, China
文摘The effects of mulching mode on population physiology and ecology of rice were studied using a combination P88S/1128 as the material under three mulching cultivation modes including plastic film mulching, straw mulching and liquid film mulching, as well as bare cultivation (control). The results indicated that mulching mode had significant effects on micro-meteorological factors and individual growth of rice, as shown by an increase of relative humidity, a better internal micro-meteorological environment of rice population, a significant reduction under the rice canopy temperature, especially during high-temperature periods. Rice plants under mulching cultivation conditions displayed a stronger transpiration and lower leaf temperature, thereby improving the ability of anti-high temperature stress and markedly increasing the photosynthetic rate. Furthermore, the yield components of rice were significantly optimized under mulching cultivation, of which with plastic film mulching displayed the highest grain number per panicle and seed-setting rate, and a yield increase of 16.81% compared with the control; and with straw mulching displayed an increase of effective panicle number and a 9.59% increase of total yield compared to the control.
基金Supported by National Modern Agricultural Industrial Technology System(CARS-02-69)Major Agriculture Science Foundation of Upland Grain Crops Breeding of Zhejiang Province(2016C02050-9-1)Project for Training of Youth Talents of Zhejiang Academy of Agricultural Sciences(2015)
文摘To investigate the effects of long-term fertilization systems on soil microbial community structure,labile organic carbon and nitrogen and enzyme activity in yellow sand paddy field and upland,a field experiment was conducted at the experimental station of Dongyang Institute of Maize Research in Zhejiang Province,China in 2009.The experiment consisted of six treatments with three replicates,and they were arranged in a completely randomized design,including no fertilization in paddy field (PCK),conventional fertilization in paddy field (PCF),formulated fertilization by soil testing in paddy field (PSTF),formulated fertilization by soil testing with organic manure in paddy field (PSTF+OF),conventional fertilization on upland (DCF),and formulated fertilization by soil testing with organic manure on upland (DSTF+OF).Soil nutrients,enzyme activity,microbial biomass and community structure were determined in 2015.The results showed that compared with no fertilization in paddy field (PCK),fertilization increased soil phosphorus and potassium content,and decreased pH value.No fertilization in paddy field (PCK) had no significant effect on soil culturable microorganisms in paddy field and upland,but formulated fertilization by soil testing with organic manure on upland (DSTF+OF) significantly increased the number of fungi.Formula fertilization by soil testing with organic manure (PSTF+OF) also significantly increased soil microbial biomass carbon and nitrogen in paddy field and upland.Moreover,fertilization had no significant effect on soil cellulase activity,but formula fertilization by soil testing with organic manure (PSTF+OF) significantly increased soil dehydrogenase and catalase activity.Therefore,long-term application of chemical fertilizer with organic fertilizer can effectively improve soil fertility.
基金supported by the project of Modern Seed Industry Enterprise Science and Technology Development of Shandong Province, China (SDKJ2012QF003)
文摘Allene oxide cyclase(AOC, E 5.3.99.6) is an essential enzyme in the jasmonic acid(JA)biosynthetic pathway and mediates a wide range of adaptive responses. In this report, five AOC genes(Gh AOC1–Gh AOC5) were cloned from upland cotton(Gossypium hirsutum L.),sequenced, and characterized. Real-time PCR analysis indicated that the transcripts of Gh AOCs were abundantly expressed in roots and less in fibers, and regulated in cotton plants under methyl jasmonate(Me JA) and Cu Cl2 stresses. To investigate the role of Gh AOC under copper stress, transgenic Arabidopsis plants overexpressing cotton Gh AOC1 under control of the Cauliflower mosaic virus 35S(Ca MV 35S) promoter were generated. Compared to untransformed plants, Gh AOC1-overexpressing Arabidopsis thaliana plants exhibited markedly higher survival rate, shoot fresh weight, shoot dry weight, and photosynthetic efficiency, and reduced cell membrane damage and lipid peroxidation under copper stress.This study provides the first evidence that Gh AOC1 plays an important role in copper stress tolerance.
基金funded by ICAR-National Rice Research Institute(NRRI)
文摘A total of 17 simple sequence repeat(SSR) markers linked to QTLs(qDTYs) governing grain yield under reproductive stage(RS) drought stress were used to assess the genetic relationship and prospecting new donors for q DTYs among 32 popular upland rice genotypes. These SSR markers generated a total of 36 alleles with an average allele count of 2.1 per locus. Polymorphic information content value of the markers ranged from 0.376 to 0.662 with an average value of 0.484. The expected heterozyogosity ranged from 0.381 to 0.632. STRUCTURE analysis divided the 32 genotypes into three sub-populations. Subsequent phenotyping revealed that all the tolerant genotypes were grouped into one sub-population, whereas the moderately tolerant and susceptible genotypes were grouped into separate sub-populations. Phylogenetic tree constructed by the unweighted neighbour-joining method also divided the genotypes into three clusters. The grouping pattern of genotypes into the clusters was similar to that into the STRUCTURE analysis, on the basis of drought tolerance level. The average value of genetic dissimilarity coefficient among the genotypes was observed to be 0.486. Furthermore, by combining genotyping data with phenotyping data, 16 new donors for 6 qDTYs were identified.
基金supported by the National Natural Science Foundation of China(31871669)
文摘With increasing demand for high-quality cotton,it is desirable to identify genes involved in fiber development for molecular improvement of cotton.In this study,780 differentially expressed genes(DEGs)were identified in developing fibers at 10 days post-anthesis(DPA)in Gossypium hirsutum acc.DH962 and G.hirsutum cv.Jimian 5 using RNA-seq.Of 15 stable QTL for fiber quality identified in the same two parents in previous studies,4,3,6,1,and 1 QTL were associated with fiber length(FL),fiber strength(FS),micronaire(MIC),fiber elongation(FE)and fiber length uniformity ratio(FU),respectively.Integration of DEGs and QTL allowed the identification of 31 genes in 9 QTL regions,of which 25 were highly expressed in fibers based on the transcriptome datasets and 9 were preferentially expressed in different stages of fiber development.Gh_A01G0453(GhDTX19),Gh_D07G1581 and Gh_D04G0942 were expressed specifically in 5 and 10 DPA fibers,with Gh_D04G0942 showing low expression in other tissues except pistil.Gh_D07G1799(GhGAUT9),Gh_D11G0326(GhVPS29),Gh_D11G0333(GhTCP14),and Gh_D11G0334(GhNRP2)were preferentially expressed in 5 or 10 DPA fibers;Gh_A01G0397(GhABCG10)and Gh_D07G1744 were expressed specifically in 20 and 25 DPA fibers.These results suggest candidate genes for molecular improvement of cotton fiber quality.
文摘Somatic embryogenesis in upland cotton isstrongly genotype-dependent,which is a troublein cotton genetic engineering.Cloning genesrelated to somatic embryogenesis and thenintroducing the gene into mainly cultivatedvarieties would be greatly helpful for cottonimprovement by gene transfer.To study
基金financial support provided by the International Development Research Center(IDRC)the Southeast Asian Regional Center for Graduate Study and Research in Agriculture(SEARCA)the National Research University Program of Thailand’s Commission on Higher Education
文摘Luang Prabang Province is located within the area recognized as the center of rice(Oryza sativa L.) diversity in Lao PDR. This study reported on grain quality characteristics of 60 upland rice seed samples sharing 49 variety names collected from 6 villages in Luang Prabang in 2015. Most of the samples has non-pigmented pericarp, while red pericarp was found in four samples and purple in five samples. Almost all of the samples were of large grain type, with glutinous endosperm in 70% and non-glutinous endosperm in 30%. The brown(unpolished) rice was found with a wide range of grain nutritional quality, including protein(9.2% ± 0.9%), Fe(15.9 ± 6.9 mg/kg), Zn(19.6 ± 2.1 mg/kg), anthocyanin(0.774 ± 0.880 mg/g), and anti-oxidative capacity(2.071 ± 1.373 mg/g). The varieties sharing similar names had similar morphological characteristics but varied in nutritional concentration, with required confirmation in genetic variation analysis. This study found that some rice varieties with high grain quality may benefit the farmers directly or could be used in varietal improvement programs.
基金supported by grants from the National Program of Plant Gene Transfer(J00-B-002-10)the National High Technology Research and Development Program of China(863 Program,2001AA212081)the Research Programs of the Ministry of Education P.C.R.(0114).
文摘A glutathione S-transferase gene (gst) has been introduced into restorers of cytoplasmic male sterility in upland cotton ( Gossypium hirsutum L. ) using Agrobacterium-mediated transformation. A transviable pollens of hybrid (sterile line×restorer) F1. The hybrid gave 3.6 more bolls per plant, 10.1% less aborted seeds and 10.6% more lint yield when ‘Zheda strong restorer’ was used as male parent than when ‘DES-HAF277’ was. Southern and Northern bloting analysis showed that the foreign gst gene was detectable and highly expressed in ‘Zheda strong restorer’.
基金financially supported by the National Natural Science Foundation of China(39790100).
文摘A field study was conducted to investigate the effects of leguminous crop cultivation on nitrousoxide (N2O) emissions from upland agricultural soils. Results demonstrated that N2O emission sequences were tively. While in terms of seasonal emission, the sequence was that soybean ＞ peanut crop ＞ upland rice, being 0.77, 0.70 and 0.55 kg/ha respectively. Results also demonstrated that legume crop treatment emitted much more N2O than non-legume upland rice treatment and that N fertilized treatments emitted more than unand N fertilizer, therefore, were one of the important sources of N2O emissions from agricultural fields.
基金supported by the Plant Breeding Research Centre for Sustainable Agriculture and Research Center of Agricultural Biotechnology for Sustainable Economy,Khon Kaen University,Thailandthe Faculty of Agriculture at Khon Kaen University for providing financial support for manuscript preparation activities
文摘The planting of upland rice is one cropping option in area with limited water availability and low soil fertility in North and Northeast Thailand.The varietal selection was determined by grain yield potential,wide adaptation,and good stability.This study was aimed at evaluation of indigenous upland rice germplasm for yield and yield stability in multi-locations.Thirty-six upland rice genotypes collected from six provinces of the North and Northeast Thailand and one check variety(Sewmaejan) were assessed under five locations in the rainy seasons of 2009 and 2010.The experiment was laid out in a randomized complete block design with three replications.The genotype grain yield was highly affected by location(59.90%),followed by genotypes(G)×location(L) interaction(12.80%) and genotype(6.79%).The most suitable location for the genotype evaluation was L3(Khon Kaen-KKU10) which associated with stability of grain yield for all genotypes.Furthermore,biplot and regression analysis indicated that genotype numbers 6(Jaowmong 1),10(Neawmong 1),18(Neawdum 1),19(Leamna),20(Prayaleamkang),32(Kunwang 2),and 33(Kunwang 3) showed great yield stability over five locations.The genotypes will be applicant for upland rice production area and parental base in breeding program.
基金sponsored by funds from the Zhongyuan Academician Foundation (212101510001)the Fundamental Research Funds for State Key Laboratory of Cotton Biology (CB2021C08)the General Program of the National Natural Science Foundation of China (31871679)
文摘Background:The utilization of heterosis has greatly improved the productivity of cotton worldwide.However,a major constraint for the large-scale promotion of F_(1) hybrid cotton is artificial emasculation and pollination.This study proposed the potential utilization of F_(2) hybrids to improve upland cotton production through a comparative evaluation of hybrid generations.Results:Eight upland cotton varieties were analyzed and crosses were made according to NCII incomplete diallel cross-breeding design in two cotton belts of China.Variance analysis revealed significant differences in agronomic,yield,and fiber quality in both generations and environments.The broad-sense heritability of agronomic and yield traits was relatively higher than quality traits.Furthermore,the narrow-sense heritability of some traits was higher in F_(2) than in the F_(1) generation in both cotton belts.Overall,parental lines Zhong901,ZB,L28,and Z98 were observed with maximum combining ability while combinations with strong special combining ability were ZB×DT,L28×Z98,and ZB×851.The yield traits heterosis was predominant in both generations.However,the level of heterosis was altered with trait,hybrid combination,generation,and environment.Interestingly,L28×Z98 performed outstandingly in Anyang.Its lint yield(LY)was 24.2%higher in F_(1) and 11.6%in F_(2) than that of the control Ruiza 816.The performance of SJ48×Z98 was excellent in Aral which showed 36.5%higher LY in F_(2)and 10.9%in F_(2)than control CCRI 49.Further results revealed most hybrid combinations had shown a low level of heterosis for agronomic and fiber quality traits in both generations.Comparatively,ZB×DT and L28×Z98 showed hybrid vigor for multiple traits in both generations and cotton belts.It is feasible to screen strong heterosis hybrid combinations with fine fiber in early generations.In the two environments,the correlation of some traits showed the same trend,and the correlation degree of Anyang site was higher than that of Aral site,and the correlation of some traits showed the opposite trend.According to the performance of strong heterosis hybrid combinations in different environments,the plant type,yield and fiber traits associated with them can be improved according to the correlation.Conclusions:Through comparative analysis of variance,combining ability,and heterosis in F_(2)and F_(2)hybrids in different cotton belts,this study proposed the potential utilization of F_(2)hybrids to improve upland cotton productivity in China.
