The use of cover crops is a promising strategy for influencing the soil microbial consortium,which is essential for the delivery of multiple soil functions(i.e.,soil multifunctionality).Nonetheless,relatively little i...The use of cover crops is a promising strategy for influencing the soil microbial consortium,which is essential for the delivery of multiple soil functions(i.e.,soil multifunctionality).Nonetheless,relatively little is known about the role of the soil microbial consortium in mediating soil multifunctionality under different cover crop amendments in dryland Ultisols.Here,we assessed the multifunctionality of soils subjected to four cover crop amendments(control,non-amended treatment;RD,radish monoculture;HV,hairy vetch monoculture;and RDHV,radish-hairy vetch mixture),and we investigated the contributions of soil microbial richness,network complexity,and ecological clusters to soil multifunctionality.Our results demonstrated that cover crops whose chemical composition differed from that of the main plant crop promoted higher multifunctionality,and the radish-hairy vetch mixture rendered the highest enhancement.We obtained evidence that changes in soil microbial richness and network complexity triggered by the cover crops were associated with higher soil multifunctionality.Specifically,specialized microbes in a key ecological cluster(ecological cluster 2)of the soil microbial network were particularly important for maintaining soil multifunctionality.Our results highlight the importance of cover crop-induced variations in functionally important taxa for promoting the soil multifunctionality of dryland Ultisols.展开更多
Combined application of chemical fertilizers with organic amendments was recommended as a strategy for improving yield,soil carbon storage,and nutrient use efficiency.However,how the long-term substitution of chemical...Combined application of chemical fertilizers with organic amendments was recommended as a strategy for improving yield,soil carbon storage,and nutrient use efficiency.However,how the long-term substitution of chemical fertilizer with organic manure affects rice yield,carbon sequestration rate(CSR),and nitrogen use efficiency(NUE)while ensuring environmental safety remains unclear.This study assessed the long-term effect of substituting chemical fertilizer with organic manure on rice yield,CSR,and NUE.It also determined the optimum substitution ratio in the acidic soil of southern China.The treatments were:(i)NPK0,unfertilized control;(ii)NPK1,100%chemical nitrogen,phosphorus,and potassium fertilizer;(iii)NPKM1,70%chemical NPK fertilizer and 30%organic manure;(iv)NPKM2,50%chemical NPK fertilizer and 50%organic manure;and(v)NPKM3,30%chemical NPK fertilizer and 70%organic manure.Milk vetch and pig manure were sources of manure for early and late rice seasons,respectively.The result showed that SOC content was higher in NPKM1,NPKM2,and NPKM3 treatments than in NPK0 and NPK1 treatments.The carbon sequestration rate increased by 140,160,and 280%under NPKM1,NPKM2,and NPKM3 treatments,respectively,compared to NPK1 treatment.Grain yield was 86.1,93.1,93.6,and 96.5%higher under NPK1,NPKM1,NPKM2,and NPKM3 treatments,respectively,compared to NPK0 treatment.The NUE in NPKM1,NPKM2,and NPKM3 treatments was higher as compared to NPK1 treatment for both rice seasons.Redundancy analysis revealed close positive relationships of CSR with C input,total N,soil C:N ratio,catalase,and humic acids,whereas NUE was closely related to grain yield,grain N content,and phenol oxidase.Furthermore,CSR and NUE negatively correlated with humin acid and soil C:P and N:P ratios.The technique for order of preference by similarity to ideal solution(TOPSIS)showed that NPKM3 treatment was the optimum strategy for improving CSR and NUE.Therefore,substituting 70%of chemical fertilizer with organic manure could be the best management option for increasing CSR and NUE in the paddy fields of southern China.展开更多
Dear Editor,Reduction in plant height has been associated with yield increases and yield stability in a number of important crop species,such as wheat and rice[1].In these plants,dwarfing is mainly attributed to the i...Dear Editor,Reduction in plant height has been associated with yield increases and yield stability in a number of important crop species,such as wheat and rice[1].In these plants,dwarfing is mainly attributed to the inability to synthesize or respond to certain phytohormones,predominantly gibberellin(GA)[2].Ideal Plant Architecture 1(IPA1),an miR156 target gene,encodes SPL14 and it is able to bind directly to the promoters of multiple GA biosynthetic,signal,and deactivating genes in rice[3].Moreover,IPA1 loss-of-function mutants exhibit dwarf phenotypes[4].展开更多
[Objectives]Selenium(Se)-enriched rice is the main type of Se-enriched agricultural product developed in China,and this study aimed to understand the impact of selenium application on the metabolites in rice.[Methods]...[Objectives]Selenium(Se)-enriched rice is the main type of Se-enriched agricultural product developed in China,and this study aimed to understand the impact of selenium application on the metabolites in rice.[Methods]Se-enriched rice was prepared by foliar application of a sodium selenite aqueous solution,and high-throughput analysis of differential metabolites in Se-enriched rice was conducted based on extensive non-targeted metabolome.[Results]There were significant differences in metabolites between Se-enriched rice and ordinary rice,and a total of 535 differential metabolites were identified.Among them,420 metabolites in Se-enriched rice were upregulated,accounting for 78.5%,far higher than downregulated metabolites.The enrichment differences of three KEGG metabolic pathways,including cysteine and methionine metabolism,zeatin biosynthesis,and arachidonic acid metabolism,reached a significant level,indicating that selenium enrichment had a significant regulatory effect on the metabolism of sulfur-containing amino acids,the synthesis of natural cytokinin zeatin,and arachidonic acid bioactive components in rice.[Conclusions]The results can provide a theoretical basis for the production of Se-enriched rice.展开更多
The flesh color of pummelo(Citrus maxima)fruits is highly diverse and largely depends on the level of carotenoids,which are beneficial to human health.It is vital to investigate the regulatory network of carotenoid bi...The flesh color of pummelo(Citrus maxima)fruits is highly diverse and largely depends on the level of carotenoids,which are beneficial to human health.It is vital to investigate the regulatory network of carotenoid biosynthesis to improve the carotenoid content in pummelo.However,the molecular mechanism underlying carotenoid accumulation in pummelo is not fully understood.In this study,we identified a novel histone methyltransferase gene,CgSDG40,involved in carotenoid regulation by analyzing the flesh transcriptome of typical white-fleshed pummelo,red-fleshed pummelo and extreme-colored F1 hybrids from a segregated pummelo population.Expression of CgSDG40 corresponded to flesh color change and was highly coexpressed with CgPSY1.Interestingly,CgSDG40 and CgPSY1 are located physically adjacent to each other on the chromosome in opposite directions,sharing a partially overlapping promoter region.Subcellular localization analysis indicated that CgSDG40 localizes to the nucleus.Overexpression of CgSDG40 significantly increased the total carotenoid content in citrus calli relative to that in wild type.In addition,expression of CgPSY1 was significantly activated in overexpression lines relative to wild type.Taken together,our findings reveal a novel histone methyltransferase regulator,CgSDG40,involved in the regulation of carotenoid biosynthesis in citrus and provide new strategies for molecular design breeding and genetic improvement of fruit color and nutritional quality.展开更多
Flowering time is important for adaptation of soybean(Glycine max)to different environments.Here,we conducted a genome-wide association study of flowering time using a panel of 1490 cultivated soybean accessions.We id...Flowering time is important for adaptation of soybean(Glycine max)to different environments.Here,we conducted a genome-wide association study of flowering time using a panel of 1490 cultivated soybean accessions.We identified three strong signals at the qFT02-2 locus(Chr02:12037319–12238569),which were associated with flowering time in three environments:Gongzhuling,Mengcheng,and Nanchang.By analyzing linkage disequilibrium,gene expression patterns,gene annotation,and the diversity of variants,we identified an AP1 homolog as the candidate gene for the qFT02-2 locus,which we named GmAP1d.Only one nonsynonymous polymorphism existed among 1490 soybean accessions at position Chr02:12087053.Accessions carrying the Chr02:12087053-T allele flowered significantly earlier than those carrying the Chr02:12087053-A allele.Thus,we developed a cleaved amplified polymorphic sequence(CAPS)marker for the SNP at Chr02:12087053,which is suitable for marker-assisted breeding of flowering time.Knockout of GmAP1d in the‘Williams 82’background by gene editing promoted flowering under long-day conditions,confirming that GmAP1d is the causal gene for qFT02-2.An analysis of the region surrounding GmAP1d revealed that GmAP1d was artificially selected during the genetic improvement of soybean.Through stepwise selection,the proportion of modern cultivars carrying the Chr02:12087053-T allele has increased,and this allele has become nearly fixed(95%)in northern China.These findings provide a theoretical basis for better understanding the molecular regulatory mechanism of flowering time in soybean and a target gene that can be used for breeding modern soybean cultivars adapted to different latitudes.展开更多
This study attempted to clarify the carrying-over effect of different nitrogen treatments applied to the main crop on the crop population growth and yield formation of ratoon rice under mechanized cultivation in South...This study attempted to clarify the carrying-over effect of different nitrogen treatments applied to the main crop on the crop population growth and yield formation of ratoon rice under mechanized cultivation in Southeast China.Based on the constant total nitrogen application amounts(225.00 kg ha;)in the main crop,an experiment with different ratios of basal and topdressing nitrogen fertilizer(the ratio of basal fertilizer:primary tillering fertilizer:secondary tillering fertilizer:booting fertilizer at 3:1:2:4(N1),3:2:1:4(N2),3:3:0:4(N3),and 4:3:0:3(N4),respectively,and a control without nitrogen treatment(N0))was set up across two consecutive years in field using hybrid rice variety Yongyou 1540 as the test materials.The results showed that the total tiller number and effective tillering percentage increased in the main crop under the N1 treatment,more nitrogen fertilizer applied in late growth stage of the main crop,and its effective tillering percentage of the main crop was the highest at up to 70.18%,which was 9.15%higher than that of conventional fertilization treatment(N4),more nitrogen fertilizer applied in early growth stage of the main crop.The same tendency was observed in leaf area index(LAI)value of the main crop and its subsequent ratoon rice,which were 16.52 and 29.87%higher,respectively,in the N1 treatment than that in the N4 treatment at the full heading stage.The same was true in the case of the transport rates of stem and sheath dry mater and the canopy light interception rates in both the main and its ratoon crops.The transport rate of stem and sheath in main crop rice under N1 treatment increased by 50.57%compared with N4 treatment.The canopy light interception rate of N1 treatment increased by 5.07%compared with N4 treatment at the full heading stage of the ratoon crop.Therefore,the total actual yield was the highest in the main and its ratoon crops under N1 treatment,averaging 17351.23 kg ha;in two-year trials,which was 23.00%higher than that in the conventional fertilization treatment(N4).The results showed that appropriate nitrogen treatment was able to produce a good crop stand in the main crop,which was essential for producing a good ratoon crop population and high yield especially under mechanized cultivation with low stubble height of the main crop.The study suggested that shifting the proper nitrogen application amounts to the late growth stage of the main crop,such as N1 treatment,not only had a higher productive effect on ensuring the yield of the main crop,but also had a positive effect on the axillary bud sprouts from the stubbles for ratoon rice,resulting in an increased percentage of productive panicles and achieving the goal of one planting with two good harvests under the conditions of our study.展开更多
In the study, an improved approach was proposed to identify the contribution shares of three group factors that are climate, technology and input, social economic factors by which the grain production is shaped. In or...In the study, an improved approach was proposed to identify the contribution shares of three group factors that are climate, technology and input, social economic factors by which the grain production is shaped. In order to calibrate the method, Jiangxi Province, one of the main paddy rice producers in China was taken as an example. Based on 50 years （1961-2010） meteorological and statistic data, using GIS and statistical analysis tools, the three group factors that in certain extent impact China＇s paddy rice production have been analyzed quantitatively. The individual and interactive contribution shares of each factor group have been identiifed via eta square （η2）. In the paper, two group ordinary leasr square （OLS） models, paddy models and climate models, have been constructed for further analysis. Each model group consists of seven models, one full model and six partial models. The results of paddy models show that climate factors individually and interactively contribute 11.42-15.25%explanatory power to the variation of paddy rice production in the studied province. Technology and input factors contribute 16.17%individually and another 8.46%interactively together with climate factors, totally contributing about 25%. Social economic factors contribute about 7%of which 4.65%is individual contribution and 2.49%is interactive contribution together with climate factors. The three factor groups individually contribute about 23%and interactively contribute additional 41%to paddy rice production. In addition every two of the three factor groups also function interactively and contribute about 22%. Among the three factor groups, technology and input are the most important factors to paddy rice production. The results of climate models support the results of paddy models, and display that solar radiation （indicated by sunshine hour variable） is the dominate climate factor for paddy rice production.展开更多
Green manure can be used as a substitute for chemical fertilizer without reducing rice yield.We studied the responses of soil fertility and rice yield to different combinations of Chinese milk vetch(CMV;Astragalus sin...Green manure can be used as a substitute for chemical fertilizer without reducing rice yield.We studied the responses of soil fertility and rice yield to different combinations of Chinese milk vetch(CMV;Astragalus sinicus L.)and chemical fertilizer in a subtropical double-rice cropping system.Our goal is to reduce chemical fertilizer use and decrease environmental contamination.Compared with the recommended rate of chemical fertilizer(CF),both early-and late-rice yields in the two treatments supplied with 15 and 22.5 Mg CMV ha^-1 plus 60%CF(represented as 60 A and 60 B,respectively)showed no significant differences while the two treatments supplied with 30 and 37.5 Mg CMV ha^-1 plus 60%CF(represented as 60 C and 60 D,respectively)showed significantly higher values.The sustainable yield index(SYI)values in the 60 C and 60 D treatments with double-rice croppong system were significantly higher than those in other treatments(P<0.05).Early-rice yield showed a significant positive relationship with the Chinese milk vetch incorporation rate.The coefficients increased annually from 2009 to 2013 and then decreased in 2014.Soil organic matter increased over time by the end of the experiment in all of the treatment groups.Soil organic matter in 60 A,60 B and 60 C showed no significant difference compared with that in CF,while soil organic matter in 60 D was significantly higher than that in CF.The slopes of soil organic matter and total nitrogen over six years were the highest in 60 C and 60 D.The soil total nitrogen content in 60 A,60 B,60 C and 60 D was higher than that in CF,but the differences were not significant(P>0.05).Therefore,a relatively high Chinese milk vetch incorporation rate(≥30 Mg ha^-1)was more effective in improving the productivity and sustainability of paddy soil.The decreased coefficients of early-rice yield and the Chinese milk vetch incorporation rate in 2014 implied that the benefits of soil fertility and rice yield created by Chinese milk vetch input may decline after five years under a continuously high rate of Chinese milk vetch incorporation.展开更多
This study was conducted to develop and characterize a novel cytoplasmic male sterile （CMS） source which was identified from Dongxiang wild rice （Oryza rufipogon） by crossing Dongxiang wild rice as female with Zho...This study was conducted to develop and characterize a novel cytoplasmic male sterile （CMS） source which was identified from Dongxiang wild rice （Oryza rufipogon） by crossing Dongxiang wild rice as female with Zhongzao 35, an indica inbred variety, as male and continuous backcrossing with Zhongzao 35. Observation under optical microscope manifested that this novel CMS belonged to typical abortion type with less pollen compared with wild abortive type cytoplasm （CMS-WA）. Sequential planting showed that this novel CMS has complete and stable male sterility. Testcross experiment showed that all the 24 tested materials including maintainer and restorer lines of CMS-WA and Honglian type cytoplasm （CMS-HL） and other indica inbred varieties are the maintainers with complete maintaining ability, suggesting that this novel CMS has fertility restoration totally different from CMS-WA and CMS-HL and belongs to a novel type of CMS. So far, we only discovered a unique fertility restoration source for this novel CMS. Inheritance analysis showed that the fertility restoration of this CMS was governed by three pairs of independent dominant genes. Prospect for application of this novel CMS system in hybrid rice breeding was also discussed.展开更多
Quantitative trait loci（QTLs） of grain traits were detected to provide theoretical basis for fine mapping and molecular marker-assisted breeding of grain traits in japonica rice.Using an F2 population including 200 ...Quantitative trait loci（QTLs） of grain traits were detected to provide theoretical basis for fine mapping and molecular marker-assisted breeding of grain traits in japonica rice.Using an F2 population including 200 individuals derived from a cross combination between two japonica rice DL115 with large grain and XL005 with small grain,the grain length,grain width,grain thickness,ratio of grain length to width and 1 000-grain weight were evaluated in Beijing;and the quantitative trait loci for above five grain traits were identified by composite interval mapping using SSR markers.The results showed that the five grain traits exhibited a normal continuous distribution in F2 population,indicating they were quantitative traits controlled by multiple genes.A total of 16 QTLs conferring the five grain traits were detected on chromosomes 2,3,5 and 12,respectively.Eight QTLs,namely qGL3a,qGW2,qGW5,qGT2,qRLW2,qRLW3,qGWT2 and qGWT3,were major QTLs and explained 15.42,40.89,13.54,33.43,13.82,13.61,12.51 and 10.1% of the observed phenotypic variance,respectively.Among them,qGW2,qGT2,qRLW2 and qGWT2 were mapped in same interval RM12776-RM324 on chromosome 2.The marker interval RM12776-RM324 on chromosome 2 was common marker intervals of four major QTLs,and the two SSR markers RM12776 and RM324 would be used in molecular markerassisted breeding in japonica rice.The modes of gene action were mainly additive and partial dominance.Four QTLs＇ alleles were derived from small grain parent XL005,and other 12 QTLs＇ alleles were derived from large grain parent DL115.The alleles from larger parent were showed significant effects to grain length,grain width,grain thickness and 1 000-grain weight.展开更多
Long non-coding RNAs(lncRNAs) play important roles in response to various biotic and abiotic stresses. So far, systematic identification and characterization of lncRNAs have been reported in a few model plant species ...Long non-coding RNAs(lncRNAs) play important roles in response to various biotic and abiotic stresses. So far, systematic identification and characterization of lncRNAs have been reported in a few model plant species and major crops, but their roles in abiotic stress response have not yet been reported in common wild rice(Oryza rufipogon). Dongxiang wild rice(DXWR) possesses a high degree of drought resistance and has been well recognized as a precious genetic resource for drought resistant rice breeding. We presented the reference catalog of 1 655 novel lncRNA transcripts in DXWR using strand-specific RNA sequencing and bioinformatics approaches. Meanwhile, a total of 1092 lncRNAs were determined as differentially expressed lncRNAs under drought stress. Quantitative real-time PCR results exhibited a high concordance with RNA sequencing data, which confirmed that the expression patterns of lncRNAs based on RNA sequencing were highly reliable. Furthermore, 8 711 transcripts were predicted as target genes of the differentially expressed lncRNAs. Functional annotation analysis based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases showed that the target genes were significantly enriched in cellular and metabolic processes, cell part, binding and plant hormone signal transduction, as well as many other terms related to abiotic stress resistance. These results expanded our understanding of lncRNA biology and provided candidate regulators for genetic improvement of drought resistance in rice cultivars.展开更多
To select the cementing and coating materials of slow/controlled-release fertilizer, the natural kaoline and abandoned foam plastics were used to prepare nano-subnanocomposites through the methods of organic material ...To select the cementing and coating materials of slow/controlled-release fertilizer, the natural kaoline and abandoned foam plastics were used to prepare nano-subnanocomposites through the methods of organic material intercalation, semiemulsification, and cut at high velocity techniques. Besides, two kinds of nano-subnanocomposites were tested in this study using several instruments, including the scanning electron microscope （SEM）, the X-ray diffraction （XRD）, the infrared ray spectrum （IR）, and the laser granularity. The main results were as follows： 1） The organic material was intercalated in the layers of kaoline clays, and the natural kaoline exfoliated into nanometer-sized layers. The organic agent and clays formed nanocomposites through hydrogen bond combination. 2） The SEM pictures of polystyrenestarch nano-subnanocomposites showed that many pores and rugas were present on the surface of film at sizes ranging from 10 to 20 nm. These nano-subnanocomposites were used as the cementing and coating materials of slow/controlledrelease fertilizer.展开更多
Reducing dietary cation-anion difference （DCAD） has been proved an effective way to prevent milk fever in dairy cows. Based on the similar physiological gastro-intestinal tract anatomy and metabolic process between ...Reducing dietary cation-anion difference （DCAD） has been proved an effective way to prevent milk fever in dairy cows. Based on the similar physiological gastro-intestinal tract anatomy and metabolic process between female goats and dairy cows, this study was conducted to evaluate the effects of varying DCAD on fluid acid-base status, plasma minerals concentration and anti-oxidative stress capacity of female goats. Urinary pH, plasma Ca, P and Mg; and anti-oxidative stress indices of total superoxide dismutase （T-SOD）, hydrogen peroxide （HzO2）, glutathione peroxidase （GSH-Px） and malondialdehyde （MDA） were determined to evaluate the effect. Forty-eight Guizhou black female goats （（15±1.9） mon of old, （22.3±3.75） kg of BW） were randomly allocated to 4 blocks of 12 goats each and were fed 1 of 4 diets differed in DCAD level （calculated as Na＋K-C1-S, mEq kg-1 DM）. Levels of DCAD were preliminarily designed to be control （＋ 150 mEq kg^-1 DM, CON）, high DCAD （＋300 mEq kg^-1 DM, HD）, low DCAD （0 mEq kg^-1 DM, LD） and negative DCAD （-150 mEq kg^-1 DM, ND）, respectively. A commercial anionic salts （Animate） and sodium bicarbonate （NaHCO3） were supplemented to reduce and increase DCAD level, respectively. There was no difference in dry matter intake for 4 groups of goats. Urine pH was aggressively decreased （P〈0.0001） with reduced DCAD and there was a strong association between DCAD and urine pH （R2=0.793, P〈0.0001）. Compared with CON and HD feeding of LD and ND resulted in greater （P〈0.05） plasma Ca concentration. Plasma P level was increased （P〈0.05） when anionic salts were supplemented. The DCAD alteration did not affected （P〉0.05） plasma Mg level. There was no significant （P〉0.05） difference in plasma GSH-Px activity and H202, but anionic salts supplementation in LD and ND significantly increased （P〈0.05） plasma T-SOD activity and tended to reduce MDA （P〈0.1） over HD and CON. Results from this study indicated that reducing DCAD could decrease urine pH and increase plasma Ca concentration of female goats. Additionally, reducing DCAD was helpful to enhance anti-oxidative stress capability of female goats.展开更多
To address the relationships between the amount of nitrogen fertilizer application and the yield of double cropping rice systems,we investigated the effects of a cultivation pattern of strong seedlings with increased ...To address the relationships between the amount of nitrogen fertilizer application and the yield of double cropping rice systems,we investigated the effects of a cultivation pattern of strong seedlings with increased planting density and reduced nitrogen application(SDN)on the morphological and physiological characteristics of double cropping rice.Our results indicated that the effects of SDN on the morphological characteristics of the single plant roots of double cropping rice were not significant,but the morphological characteristics of the population roots were largely different.Specifically,SDN significantly increased the morphological indexes of the root population such as root fresh weight,root volume,root number,root length and root dry weight.The effects of SDN on the total root absorption areas and root active absorption areas of the single plants were non-significant,but it dramatically enhanced the total root absorption areas and root active absorption areas of the plant population during the tillering,heading and mature stages.In addition,SDN significantly increased the root bleeding intensity and elevated the soluble sugar and free amino acid contents of root bleeding sap.Compared to the traditional cultivation pattern(CK),SDN significantly increased root bleeding intensity at the heading stage by 4.37 and 8.90% for early and late rice,respectively.Meanwhile,SDN profoundly enhanced the soluble sugar contents of root bleeding sap by 12.85 and 10.41% for early and late rice,respectively.In addition,SDN also significantly enhanced free amino acid content of root bleeding sap by 43.25% for early rice and by 37.50% for late rice systems compared to CK.Furthermore,SDN increased the actual yield of double cropping rice mainly due to the higher effective panicle number and the larger seedsetting rate.The actual yields of early rice under SDN were higher than CK by 9.37 and 5.98% in 2016 and 2017,and the actual yields of late rice under SDN were higher than CK by 0.20 and 1.41% in 2016 and 2017,respectively.Correlation analysis indicated that the significant positive correlations were observed between the majority of the root indexes and the actual yield across the four different growth stages.展开更多
MicroRNAs （miRNAs） are non-coding small RNAs, which play important regulatory roles in response to biotic and abiotic stresses. Dongxiang wild rice （Oryza rufipogon, DXWR） can survive in extreme drought environmen...MicroRNAs （miRNAs） are non-coding small RNAs, which play important regulatory roles in response to biotic and abiotic stresses. Dongxiang wild rice （Oryza rufipogon, DXWR） can survive in extreme drought environment, but its molecular mechanism of drought resistance is still largely unknown. To further explore miRNA regulatory mechanisms involved in drought resistance, we identified 138 novel miRNAs in DXWR using small RNA sequencing and bioinformatics approaches, and found that the expression levels of 67 novel miRNAs were significantly affected by drought stress. In total, 200 candidate target genes were predicted and annotated for the drought stress-responsive novel miRNAs. Gene Ontology （GO） analysis and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathways suggested that most of the target genes were related to metabolism. Stem-loop quantitative real-time PCR （qRT-PCR） results exhibited high concordance with sequencing data, which confirmed that miRNA expression patterns based on small RNA sequencing in the present study were reliable. Meanwhile, qRT-PCR validated the inverse expression patterns between several miRNAs and their target genes. These results will enhance our understanding of miRNA regulatory mechanisms in response to drought stress in DXWR, and can serve as an important reference for the protection and utilization of this valuable genetic resource.展开更多
To construct the T-DNA insertional mutagenesis transformation system for rice sheath blight pathogen Rhizoctonia solani AG-1 IA,the virulent isolate GD118 of this pathogen was selected as an initial isolate for transf...To construct the T-DNA insertional mutagenesis transformation system for rice sheath blight pathogen Rhizoctonia solani AG-1 IA,the virulent isolate GD118 of this pathogen was selected as an initial isolate for transformation.The conditions for transformation of isolate GD118 were optimized in five aspects,i.e.pre-induction time,co-culture time,acetosyringone(AS) concentration at the co-culture phase,co-culture temperature and pH value of induction solid medium(ISM) at the co-culture phase.Finally,a system of Agrobacterium tumefaciens-mediated transformation(ATMT) for R.solani AG-1 IA was established successfully.The optimal conditions for this ATMT system were as follows:the concentration of hygromycin B at 30 μg/mL for transformant screening,8 h of pre-induction,20 h of co-culture,200 μmol/L of AS in ISM,co-culture at 25 ℃ and pH 5.6 to 5.8 of ISM at the co-culture phase.The transformants still displayed high resistance to hygromycin B after subculture for five generations.A total of 10 randomly selected transformants were used for PCR verification using the specific primers designed for the hph gene,and the results revealed that an expected band of 500 bp was amplified from all of the 10 transformants.Moreover,PCR amplification for these 10 transformants was carried out using specific primers designed for the Vir gene of A.tumefaciens,with four strains of A.tumefaciens as positive controls for eliminating the false-positive caused by the contamination of A.tumefaciens.An expected band of 730 bp was amplified from the four strains of A.tumefaciens,whereas no corresponding DNA band could be amplified from the 10 transformants.The results of the two PCR amplifications clearly showed that T-DNA was indeed inserted into the genome of target isolate GD118.展开更多
A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B / Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper res...A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B / Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper resistance and yield traits. A linkage map consisting of 119 DNA markers and spanned for 1188 cM over the 12 rice chromosomes was constructed. Thirty-two chromosomal segment substitution lines were selected based on the percentage of Xieqingzao B allele at marker loci. These lines are of great potential for gene mapping and alien gene introgression.展开更多
To identify the function of differential expression proteins in different leaves of rice seedlings extracted from 2- to 5-leaf stages, the leaf proteins at the seedling stage of hybrid rice Shanyou 63 were studied by ...To identify the function of differential expression proteins in different leaves of rice seedlings extracted from 2- to 5-leaf stages, the leaf proteins at the seedling stage of hybrid rice Shanyou 63 were studied by using the approach of plant proteomics, and those proteins were separated with two-dimensional electrophoresis （2-DE） and then analyzed with an imagemaster 2D Elite 5.0. The results showed that the 41 protein spots were detected differential expression, of which 17 new protein spots appeared after the 3-leaf stage, including 9 special protein spots, which were only detected at the 3-leaf stage. Thirteen protein spots increased first and then decreased in expression abundance gradually and finally even disappeared. For the other 11 protein spots, 3 protein spots decreased, but 6 protein spots were opposite in expression abundance, however, 2 protein spots expressed in an irregular pattern after the 2-leaf stage. Of the 41 differential leaf proteins, 15 protein spots were identified by ESI-Q MS/MS and categorized into 4 groups of functions. The results indicated that proteins were the carriers of the functions in cells, but were significantly influenced by the changes in cell function or intercellular environment; hence, the reason that caused the proteomic changes as mentioned earlier might be related to the occurrence of tillers at the rice seedling stage after the 3-leaf stage.展开更多
Glyphosate-tolerant soybean is the most widely planted genetically modified crop worldwide. However, soybean remains recalcitrant to routine transformation because of the low infection efficiency of Agrobacterium to s...Glyphosate-tolerant soybean is the most widely planted genetically modified crop worldwide. However, soybean remains recalcitrant to routine transformation because of the low infection efficiency of Agrobacterium to soybean and lack of useful selectable markers. In this study, several Agrobacterium strains and cell densities were compared by transient expression of the GUS gene. The results showed that Agrobacterium strain Ag10 at cell densities of OD_(600) of 0.6–0.9 yielded the highest infection efficiency in Agrobacterium-mediated soybean cotyledonary node transformation system. Meanwhile, a simple and rapid method was developed for identification of glyphosate tolerance in putative T_0 transgenic plants, consisting of spotting plantlets with 1 μL Roundup~?. The whole cycle of genetic transformation could be shortened to about 3 mon by highly efficient selection with glyphosate during the transformation process and application of the spot assay in putative T_0 transgenic plantlets. The transformation frequency ranged from 2.9 to 5.6%. This study provides an improved protocol for development and identification of glyphosate-tolerant transgenic soybeans.展开更多
基金supported by the National Key Research and Development Program of China(2021YFD1901201-05)the China Agriculture Research System of MOF and MARA(CARS-22)+1 种基金the Special Program for Basic Research and Talent Training of Jiangxi Academy of Agricultural Sciences,China(JXSNKYJCRC202301 and JXSNKYJCRC202325)the National Natural Science Foundation of China(32160766).
文摘The use of cover crops is a promising strategy for influencing the soil microbial consortium,which is essential for the delivery of multiple soil functions(i.e.,soil multifunctionality).Nonetheless,relatively little is known about the role of the soil microbial consortium in mediating soil multifunctionality under different cover crop amendments in dryland Ultisols.Here,we assessed the multifunctionality of soils subjected to four cover crop amendments(control,non-amended treatment;RD,radish monoculture;HV,hairy vetch monoculture;and RDHV,radish-hairy vetch mixture),and we investigated the contributions of soil microbial richness,network complexity,and ecological clusters to soil multifunctionality.Our results demonstrated that cover crops whose chemical composition differed from that of the main plant crop promoted higher multifunctionality,and the radish-hairy vetch mixture rendered the highest enhancement.We obtained evidence that changes in soil microbial richness and network complexity triggered by the cover crops were associated with higher soil multifunctionality.Specifically,specialized microbes in a key ecological cluster(ecological cluster 2)of the soil microbial network were particularly important for maintaining soil multifunctionality.Our results highlight the importance of cover crop-induced variations in functionally important taxa for promoting the soil multifunctionality of dryland Ultisols.
基金supported by the National Natural Science Foundation of China (41671301)the National Key Research and Development Program of China (2016YFD0300901)the Central Public-interest Scientific Institution Basal Research Fund, China (GY2022-13-5, G2022-02-2, G2022-02-3 and G2022-02-10)
文摘Combined application of chemical fertilizers with organic amendments was recommended as a strategy for improving yield,soil carbon storage,and nutrient use efficiency.However,how the long-term substitution of chemical fertilizer with organic manure affects rice yield,carbon sequestration rate(CSR),and nitrogen use efficiency(NUE)while ensuring environmental safety remains unclear.This study assessed the long-term effect of substituting chemical fertilizer with organic manure on rice yield,CSR,and NUE.It also determined the optimum substitution ratio in the acidic soil of southern China.The treatments were:(i)NPK0,unfertilized control;(ii)NPK1,100%chemical nitrogen,phosphorus,and potassium fertilizer;(iii)NPKM1,70%chemical NPK fertilizer and 30%organic manure;(iv)NPKM2,50%chemical NPK fertilizer and 50%organic manure;and(v)NPKM3,30%chemical NPK fertilizer and 70%organic manure.Milk vetch and pig manure were sources of manure for early and late rice seasons,respectively.The result showed that SOC content was higher in NPKM1,NPKM2,and NPKM3 treatments than in NPK0 and NPK1 treatments.The carbon sequestration rate increased by 140,160,and 280%under NPKM1,NPKM2,and NPKM3 treatments,respectively,compared to NPK1 treatment.Grain yield was 86.1,93.1,93.6,and 96.5%higher under NPK1,NPKM1,NPKM2,and NPKM3 treatments,respectively,compared to NPK0 treatment.The NUE in NPKM1,NPKM2,and NPKM3 treatments was higher as compared to NPK1 treatment for both rice seasons.Redundancy analysis revealed close positive relationships of CSR with C input,total N,soil C:N ratio,catalase,and humic acids,whereas NUE was closely related to grain yield,grain N content,and phenol oxidase.Furthermore,CSR and NUE negatively correlated with humin acid and soil C:P and N:P ratios.The technique for order of preference by similarity to ideal solution(TOPSIS)showed that NPKM3 treatment was the optimum strategy for improving CSR and NUE.Therefore,substituting 70%of chemical fertilizer with organic manure could be the best management option for increasing CSR and NUE in the paddy fields of southern China.
基金Thisworkwas funded by the National Natural Science Foundation of China(grants 31960433 and 31860562)Natural Science Foundation of Jiangxi Province(grant 20171ACB20001).
文摘Dear Editor,Reduction in plant height has been associated with yield increases and yield stability in a number of important crop species,such as wheat and rice[1].In these plants,dwarfing is mainly attributed to the inability to synthesize or respond to certain phytohormones,predominantly gibberellin(GA)[2].Ideal Plant Architecture 1(IPA1),an miR156 target gene,encodes SPL14 and it is able to bind directly to the promoters of multiple GA biosynthetic,signal,and deactivating genes in rice[3].Moreover,IPA1 loss-of-function mutants exhibit dwarf phenotypes[4].
基金Supported by National Natural Science Foundation of China(32260067)National Key R&D Program of China(20202BBF63011)Innovative Research and Industrial Demonstration of Standardized Production Technology for Seleniumenriched Rice and Vegetables(20202BBF62001)。
文摘[Objectives]Selenium(Se)-enriched rice is the main type of Se-enriched agricultural product developed in China,and this study aimed to understand the impact of selenium application on the metabolites in rice.[Methods]Se-enriched rice was prepared by foliar application of a sodium selenite aqueous solution,and high-throughput analysis of differential metabolites in Se-enriched rice was conducted based on extensive non-targeted metabolome.[Results]There were significant differences in metabolites between Se-enriched rice and ordinary rice,and a total of 535 differential metabolites were identified.Among them,420 metabolites in Se-enriched rice were upregulated,accounting for 78.5%,far higher than downregulated metabolites.The enrichment differences of three KEGG metabolic pathways,including cysteine and methionine metabolism,zeatin biosynthesis,and arachidonic acid metabolism,reached a significant level,indicating that selenium enrichment had a significant regulatory effect on the metabolism of sulfur-containing amino acids,the synthesis of natural cytokinin zeatin,and arachidonic acid bioactive components in rice.[Conclusions]The results can provide a theoretical basis for the production of Se-enriched rice.
基金supported by the Major Special Projects and Key R&D Projects in Yunnan Province,China(202102AE090054)the National Natural Science Foundation of China(31925034)+1 种基金the Foundation of Hubei Hongshan Laboratory granted to Dr.Qiang Xu,China(2021hszd016)the Key Project of Hubei Provincial Natural Science Foundation,China(2021CFA017)。
文摘The flesh color of pummelo(Citrus maxima)fruits is highly diverse and largely depends on the level of carotenoids,which are beneficial to human health.It is vital to investigate the regulatory network of carotenoid biosynthesis to improve the carotenoid content in pummelo.However,the molecular mechanism underlying carotenoid accumulation in pummelo is not fully understood.In this study,we identified a novel histone methyltransferase gene,CgSDG40,involved in carotenoid regulation by analyzing the flesh transcriptome of typical white-fleshed pummelo,red-fleshed pummelo and extreme-colored F1 hybrids from a segregated pummelo population.Expression of CgSDG40 corresponded to flesh color change and was highly coexpressed with CgPSY1.Interestingly,CgSDG40 and CgPSY1 are located physically adjacent to each other on the chromosome in opposite directions,sharing a partially overlapping promoter region.Subcellular localization analysis indicated that CgSDG40 localizes to the nucleus.Overexpression of CgSDG40 significantly increased the total carotenoid content in citrus calli relative to that in wild type.In addition,expression of CgPSY1 was significantly activated in overexpression lines relative to wild type.Taken together,our findings reveal a novel histone methyltransferase regulator,CgSDG40,involved in the regulation of carotenoid biosynthesis in citrus and provide new strategies for molecular design breeding and genetic improvement of fruit color and nutritional quality.
基金supported by the National Natural Science Foundation of China(U22A20473)the National Key Research and Development Program of China(2021YFD1201600)+2 种基金the China Agriculture Research System(CARS-04-PS01)the Agricultural Science and Technology Innovation Program(ASTIP)of Chinese Academy of Agricultural Sciences,Scientific Innovation 2030 Project(2022ZD0401703)the Platform of National Crop Germplasm Resources of China。
文摘Flowering time is important for adaptation of soybean(Glycine max)to different environments.Here,we conducted a genome-wide association study of flowering time using a panel of 1490 cultivated soybean accessions.We identified three strong signals at the qFT02-2 locus(Chr02:12037319–12238569),which were associated with flowering time in three environments:Gongzhuling,Mengcheng,and Nanchang.By analyzing linkage disequilibrium,gene expression patterns,gene annotation,and the diversity of variants,we identified an AP1 homolog as the candidate gene for the qFT02-2 locus,which we named GmAP1d.Only one nonsynonymous polymorphism existed among 1490 soybean accessions at position Chr02:12087053.Accessions carrying the Chr02:12087053-T allele flowered significantly earlier than those carrying the Chr02:12087053-A allele.Thus,we developed a cleaved amplified polymorphic sequence(CAPS)marker for the SNP at Chr02:12087053,which is suitable for marker-assisted breeding of flowering time.Knockout of GmAP1d in the‘Williams 82’background by gene editing promoted flowering under long-day conditions,confirming that GmAP1d is the causal gene for qFT02-2.An analysis of the region surrounding GmAP1d revealed that GmAP1d was artificially selected during the genetic improvement of soybean.Through stepwise selection,the proportion of modern cultivars carrying the Chr02:12087053-T allele has increased,and this allele has become nearly fixed(95%)in northern China.These findings provide a theoretical basis for better understanding the molecular regulatory mechanism of flowering time in soybean and a target gene that can be used for breeding modern soybean cultivars adapted to different latitudes.
基金funded by the National Key Research and Development Program of China(2016YFD0300508,2017YFD0301602 and 2018YFD0301105)the FujianTaiwan Joint Innovative Centre for Germplasm Resources and Cultivation of Crop,China(Fujian 2011 Program+1 种基金2015-75)the Science and Technology Development Fund of Fujian Agriculture and Forestry University,China(KF2015043)。
文摘This study attempted to clarify the carrying-over effect of different nitrogen treatments applied to the main crop on the crop population growth and yield formation of ratoon rice under mechanized cultivation in Southeast China.Based on the constant total nitrogen application amounts(225.00 kg ha;)in the main crop,an experiment with different ratios of basal and topdressing nitrogen fertilizer(the ratio of basal fertilizer:primary tillering fertilizer:secondary tillering fertilizer:booting fertilizer at 3:1:2:4(N1),3:2:1:4(N2),3:3:0:4(N3),and 4:3:0:3(N4),respectively,and a control without nitrogen treatment(N0))was set up across two consecutive years in field using hybrid rice variety Yongyou 1540 as the test materials.The results showed that the total tiller number and effective tillering percentage increased in the main crop under the N1 treatment,more nitrogen fertilizer applied in late growth stage of the main crop,and its effective tillering percentage of the main crop was the highest at up to 70.18%,which was 9.15%higher than that of conventional fertilization treatment(N4),more nitrogen fertilizer applied in early growth stage of the main crop.The same tendency was observed in leaf area index(LAI)value of the main crop and its subsequent ratoon rice,which were 16.52 and 29.87%higher,respectively,in the N1 treatment than that in the N4 treatment at the full heading stage.The same was true in the case of the transport rates of stem and sheath dry mater and the canopy light interception rates in both the main and its ratoon crops.The transport rate of stem and sheath in main crop rice under N1 treatment increased by 50.57%compared with N4 treatment.The canopy light interception rate of N1 treatment increased by 5.07%compared with N4 treatment at the full heading stage of the ratoon crop.Therefore,the total actual yield was the highest in the main and its ratoon crops under N1 treatment,averaging 17351.23 kg ha;in two-year trials,which was 23.00%higher than that in the conventional fertilization treatment(N4).The results showed that appropriate nitrogen treatment was able to produce a good crop stand in the main crop,which was essential for producing a good ratoon crop population and high yield especially under mechanized cultivation with low stubble height of the main crop.The study suggested that shifting the proper nitrogen application amounts to the late growth stage of the main crop,such as N1 treatment,not only had a higher productive effect on ensuring the yield of the main crop,but also had a positive effect on the axillary bud sprouts from the stubbles for ratoon rice,resulting in an increased percentage of productive panicles and achieving the goal of one planting with two good harvests under the conditions of our study.
基金financed by the National Basic Research Program of China(2010CB951502)
文摘In the study, an improved approach was proposed to identify the contribution shares of three group factors that are climate, technology and input, social economic factors by which the grain production is shaped. In order to calibrate the method, Jiangxi Province, one of the main paddy rice producers in China was taken as an example. Based on 50 years （1961-2010） meteorological and statistic data, using GIS and statistical analysis tools, the three group factors that in certain extent impact China＇s paddy rice production have been analyzed quantitatively. The individual and interactive contribution shares of each factor group have been identiifed via eta square （η2）. In the paper, two group ordinary leasr square （OLS） models, paddy models and climate models, have been constructed for further analysis. Each model group consists of seven models, one full model and six partial models. The results of paddy models show that climate factors individually and interactively contribute 11.42-15.25%explanatory power to the variation of paddy rice production in the studied province. Technology and input factors contribute 16.17%individually and another 8.46%interactively together with climate factors, totally contributing about 25%. Social economic factors contribute about 7%of which 4.65%is individual contribution and 2.49%is interactive contribution together with climate factors. The three factor groups individually contribute about 23%and interactively contribute additional 41%to paddy rice production. In addition every two of the three factor groups also function interactively and contribute about 22%. Among the three factor groups, technology and input are the most important factors to paddy rice production. The results of climate models support the results of paddy models, and display that solar radiation （indicated by sunshine hour variable） is the dominate climate factor for paddy rice production.
基金funded by the National Key Research and Development Program of China(2016YFD0800500 and 2016YFD0200800)the National Natural Science Foundation of China(31860592)+2 种基金the earmarked fund for China Agriculture Research System(CARS-22-Z-06)the Special Scientific Research Fund of Agricultural Public Welfare Profession of China(201503123-07)the Innovation Fund of Jiangxi Academy of Agricultural Sciences,China(2015CBS007 and 20182CBS002)。
文摘Green manure can be used as a substitute for chemical fertilizer without reducing rice yield.We studied the responses of soil fertility and rice yield to different combinations of Chinese milk vetch(CMV;Astragalus sinicus L.)and chemical fertilizer in a subtropical double-rice cropping system.Our goal is to reduce chemical fertilizer use and decrease environmental contamination.Compared with the recommended rate of chemical fertilizer(CF),both early-and late-rice yields in the two treatments supplied with 15 and 22.5 Mg CMV ha^-1 plus 60%CF(represented as 60 A and 60 B,respectively)showed no significant differences while the two treatments supplied with 30 and 37.5 Mg CMV ha^-1 plus 60%CF(represented as 60 C and 60 D,respectively)showed significantly higher values.The sustainable yield index(SYI)values in the 60 C and 60 D treatments with double-rice croppong system were significantly higher than those in other treatments(P<0.05).Early-rice yield showed a significant positive relationship with the Chinese milk vetch incorporation rate.The coefficients increased annually from 2009 to 2013 and then decreased in 2014.Soil organic matter increased over time by the end of the experiment in all of the treatment groups.Soil organic matter in 60 A,60 B and 60 C showed no significant difference compared with that in CF,while soil organic matter in 60 D was significantly higher than that in CF.The slopes of soil organic matter and total nitrogen over six years were the highest in 60 C and 60 D.The soil total nitrogen content in 60 A,60 B,60 C and 60 D was higher than that in CF,but the differences were not significant(P>0.05).Therefore,a relatively high Chinese milk vetch incorporation rate(≥30 Mg ha^-1)was more effective in improving the productivity and sustainability of paddy soil.The decreased coefficients of early-rice yield and the Chinese milk vetch incorporation rate in 2014 implied that the benefits of soil fertility and rice yield created by Chinese milk vetch input may decline after five years under a continuously high rate of Chinese milk vetch incorporation.
基金supported by the Key Program for Scienceand Technology of Jiangxi ProvinceChina(Grant No.20114ABF03101)+1 种基金the Program of Advantage Group forInnovation of Science and Technology of Jiangxi ProvinceChina(Grant No.20115BCB29019)
文摘This study was conducted to develop and characterize a novel cytoplasmic male sterile （CMS） source which was identified from Dongxiang wild rice （Oryza rufipogon） by crossing Dongxiang wild rice as female with Zhongzao 35, an indica inbred variety, as male and continuous backcrossing with Zhongzao 35. Observation under optical microscope manifested that this novel CMS belonged to typical abortion type with less pollen compared with wild abortive type cytoplasm （CMS-WA）. Sequential planting showed that this novel CMS has complete and stable male sterility. Testcross experiment showed that all the 24 tested materials including maintainer and restorer lines of CMS-WA and Honglian type cytoplasm （CMS-HL） and other indica inbred varieties are the maintainers with complete maintaining ability, suggesting that this novel CMS has fertility restoration totally different from CMS-WA and CMS-HL and belongs to a novel type of CMS. So far, we only discovered a unique fertility restoration source for this novel CMS. Inheritance analysis showed that the fertility restoration of this CMS was governed by three pairs of independent dominant genes. Prospect for application of this novel CMS system in hybrid rice breeding was also discussed.
基金supported by the National Key Technologies R&D Program of China (2006BAD13B01)the National Basic Research Program of China(2005DKA21001-01)the National Crop Resources Protect Program of China [NB06-070401(22-27)-01]
文摘Quantitative trait loci（QTLs） of grain traits were detected to provide theoretical basis for fine mapping and molecular marker-assisted breeding of grain traits in japonica rice.Using an F2 population including 200 individuals derived from a cross combination between two japonica rice DL115 with large grain and XL005 with small grain,the grain length,grain width,grain thickness,ratio of grain length to width and 1 000-grain weight were evaluated in Beijing;and the quantitative trait loci for above five grain traits were identified by composite interval mapping using SSR markers.The results showed that the five grain traits exhibited a normal continuous distribution in F2 population,indicating they were quantitative traits controlled by multiple genes.A total of 16 QTLs conferring the five grain traits were detected on chromosomes 2,3,5 and 12,respectively.Eight QTLs,namely qGL3a,qGW2,qGW5,qGT2,qRLW2,qRLW3,qGWT2 and qGWT3,were major QTLs and explained 15.42,40.89,13.54,33.43,13.82,13.61,12.51 and 10.1% of the observed phenotypic variance,respectively.Among them,qGW2,qGT2,qRLW2 and qGWT2 were mapped in same interval RM12776-RM324 on chromosome 2.The marker interval RM12776-RM324 on chromosome 2 was common marker intervals of four major QTLs,and the two SSR markers RM12776 and RM324 would be used in molecular markerassisted breeding in japonica rice.The modes of gene action were mainly additive and partial dominance.Four QTLs＇ alleles were derived from small grain parent XL005,and other 12 QTLs＇ alleles were derived from large grain parent DL115.The alleles from larger parent were showed significant effects to grain length,grain width,grain thickness and 1 000-grain weight.
基金supported by the National Natural Science Foundation of China (Grant No. 31660386)the Natural Science Foundation of Jiangxi Province for Distinguished Young Scholars (Grant No. 20171BCB23040)+1 种基金the Foundation of Jiangxi Educational Committee (Grant No. GJJ170193)the Sponsored Program for Distinguished Young Scholars in Jiangxi Normal University, China
文摘Long non-coding RNAs(lncRNAs) play important roles in response to various biotic and abiotic stresses. So far, systematic identification and characterization of lncRNAs have been reported in a few model plant species and major crops, but their roles in abiotic stress response have not yet been reported in common wild rice(Oryza rufipogon). Dongxiang wild rice(DXWR) possesses a high degree of drought resistance and has been well recognized as a precious genetic resource for drought resistant rice breeding. We presented the reference catalog of 1 655 novel lncRNA transcripts in DXWR using strand-specific RNA sequencing and bioinformatics approaches. Meanwhile, a total of 1092 lncRNAs were determined as differentially expressed lncRNAs under drought stress. Quantitative real-time PCR results exhibited a high concordance with RNA sequencing data, which confirmed that the expression patterns of lncRNAs based on RNA sequencing were highly reliable. Furthermore, 8 711 transcripts were predicted as target genes of the differentially expressed lncRNAs. Functional annotation analysis based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases showed that the target genes were significantly enriched in cellular and metabolic processes, cell part, binding and plant hormone signal transduction, as well as many other terms related to abiotic stress resistance. These results expanded our understanding of lncRNA biology and provided candidate regulators for genetic improvement of drought resistance in rice cultivars.
文摘To select the cementing and coating materials of slow/controlled-release fertilizer, the natural kaoline and abandoned foam plastics were used to prepare nano-subnanocomposites through the methods of organic material intercalation, semiemulsification, and cut at high velocity techniques. Besides, two kinds of nano-subnanocomposites were tested in this study using several instruments, including the scanning electron microscope （SEM）, the X-ray diffraction （XRD）, the infrared ray spectrum （IR）, and the laser granularity. The main results were as follows： 1） The organic material was intercalated in the layers of kaoline clays, and the natural kaoline exfoliated into nanometer-sized layers. The organic agent and clays formed nanocomposites through hydrogen bond combination. 2） The SEM pictures of polystyrenestarch nano-subnanocomposites showed that many pores and rugas were present on the surface of film at sizes ranging from 10 to 20 nm. These nano-subnanocomposites were used as the cementing and coating materials of slow/controlledrelease fertilizer.
基金funded by the National Natural Science Foundation of China (30901038, 31160468)the State Key Laboratory of Animal Nutrition, Ministry of Science and Technology, China (2004DA125184F1115)the Key Technology Research and Development Program of Guizhou Province, China ([2009]3085)
文摘Reducing dietary cation-anion difference （DCAD） has been proved an effective way to prevent milk fever in dairy cows. Based on the similar physiological gastro-intestinal tract anatomy and metabolic process between female goats and dairy cows, this study was conducted to evaluate the effects of varying DCAD on fluid acid-base status, plasma minerals concentration and anti-oxidative stress capacity of female goats. Urinary pH, plasma Ca, P and Mg; and anti-oxidative stress indices of total superoxide dismutase （T-SOD）, hydrogen peroxide （HzO2）, glutathione peroxidase （GSH-Px） and malondialdehyde （MDA） were determined to evaluate the effect. Forty-eight Guizhou black female goats （（15±1.9） mon of old, （22.3±3.75） kg of BW） were randomly allocated to 4 blocks of 12 goats each and were fed 1 of 4 diets differed in DCAD level （calculated as Na＋K-C1-S, mEq kg-1 DM）. Levels of DCAD were preliminarily designed to be control （＋ 150 mEq kg^-1 DM, CON）, high DCAD （＋300 mEq kg^-1 DM, HD）, low DCAD （0 mEq kg^-1 DM, LD） and negative DCAD （-150 mEq kg^-1 DM, ND）, respectively. A commercial anionic salts （Animate） and sodium bicarbonate （NaHCO3） were supplemented to reduce and increase DCAD level, respectively. There was no difference in dry matter intake for 4 groups of goats. Urine pH was aggressively decreased （P〈0.0001） with reduced DCAD and there was a strong association between DCAD and urine pH （R2=0.793, P〈0.0001）. Compared with CON and HD feeding of LD and ND resulted in greater （P〈0.05） plasma Ca concentration. Plasma P level was increased （P〈0.05） when anionic salts were supplemented. The DCAD alteration did not affected （P〉0.05） plasma Mg level. There was no significant （P〉0.05） difference in plasma GSH-Px activity and H202, but anionic salts supplementation in LD and ND significantly increased （P〈0.05） plasma T-SOD activity and tended to reduce MDA （P〈0.1） over HD and CON. Results from this study indicated that reducing DCAD could decrease urine pH and increase plasma Ca concentration of female goats. Additionally, reducing DCAD was helpful to enhance anti-oxidative stress capability of female goats.
基金financially supported by the National Key Research and Development Program of China(2017YFD0300106,2018YFD0301103,and 2016YFD0300108)the National Key Technologies R&D Program of China during the 12th Five-Year Plan period(2013BAD07B12)the National Natural Science Foundation of China(31601263)。
文摘To address the relationships between the amount of nitrogen fertilizer application and the yield of double cropping rice systems,we investigated the effects of a cultivation pattern of strong seedlings with increased planting density and reduced nitrogen application(SDN)on the morphological and physiological characteristics of double cropping rice.Our results indicated that the effects of SDN on the morphological characteristics of the single plant roots of double cropping rice were not significant,but the morphological characteristics of the population roots were largely different.Specifically,SDN significantly increased the morphological indexes of the root population such as root fresh weight,root volume,root number,root length and root dry weight.The effects of SDN on the total root absorption areas and root active absorption areas of the single plants were non-significant,but it dramatically enhanced the total root absorption areas and root active absorption areas of the plant population during the tillering,heading and mature stages.In addition,SDN significantly increased the root bleeding intensity and elevated the soluble sugar and free amino acid contents of root bleeding sap.Compared to the traditional cultivation pattern(CK),SDN significantly increased root bleeding intensity at the heading stage by 4.37 and 8.90% for early and late rice,respectively.Meanwhile,SDN profoundly enhanced the soluble sugar contents of root bleeding sap by 12.85 and 10.41% for early and late rice,respectively.In addition,SDN also significantly enhanced free amino acid content of root bleeding sap by 43.25% for early rice and by 37.50% for late rice systems compared to CK.Furthermore,SDN increased the actual yield of double cropping rice mainly due to the higher effective panicle number and the larger seedsetting rate.The actual yields of early rice under SDN were higher than CK by 9.37 and 5.98% in 2016 and 2017,and the actual yields of late rice under SDN were higher than CK by 0.20 and 1.41% in 2016 and 2017,respectively.Correlation analysis indicated that the significant positive correlations were observed between the majority of the root indexes and the actual yield across the four different growth stages.
基金supported by the National Natural Science Foundation of China(Grant No.31660386)the Natural Science Foundation of Jiangxi Province for Distinguished Young Scholars(Grant No.20171 BCB23040)+1 种基金the Foundation of Jiangxi Educational Committee(Grant No.GJJ170193)the Sponsored Program for Distinguished Young Scholars in Jiangxi Normal University,China
文摘MicroRNAs （miRNAs） are non-coding small RNAs, which play important regulatory roles in response to biotic and abiotic stresses. Dongxiang wild rice （Oryza rufipogon, DXWR） can survive in extreme drought environment, but its molecular mechanism of drought resistance is still largely unknown. To further explore miRNA regulatory mechanisms involved in drought resistance, we identified 138 novel miRNAs in DXWR using small RNA sequencing and bioinformatics approaches, and found that the expression levels of 67 novel miRNAs were significantly affected by drought stress. In total, 200 candidate target genes were predicted and annotated for the drought stress-responsive novel miRNAs. Gene Ontology （GO） analysis and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathways suggested that most of the target genes were related to metabolism. Stem-loop quantitative real-time PCR （qRT-PCR） results exhibited high concordance with sequencing data, which confirmed that miRNA expression patterns based on small RNA sequencing in the present study were reliable. Meanwhile, qRT-PCR validated the inverse expression patterns between several miRNAs and their target genes. These results will enhance our understanding of miRNA regulatory mechanisms in response to drought stress in DXWR, and can serve as an important reference for the protection and utilization of this valuable genetic resource.
基金supported by a ‘Special Fund for Agro-scientific Research in the Public Interest’ from the Ministry of Agriculture of China(Grant No.nyhyzx3-16)
文摘To construct the T-DNA insertional mutagenesis transformation system for rice sheath blight pathogen Rhizoctonia solani AG-1 IA,the virulent isolate GD118 of this pathogen was selected as an initial isolate for transformation.The conditions for transformation of isolate GD118 were optimized in five aspects,i.e.pre-induction time,co-culture time,acetosyringone(AS) concentration at the co-culture phase,co-culture temperature and pH value of induction solid medium(ISM) at the co-culture phase.Finally,a system of Agrobacterium tumefaciens-mediated transformation(ATMT) for R.solani AG-1 IA was established successfully.The optimal conditions for this ATMT system were as follows:the concentration of hygromycin B at 30 μg/mL for transformant screening,8 h of pre-induction,20 h of co-culture,200 μmol/L of AS in ISM,co-culture at 25 ℃ and pH 5.6 to 5.8 of ISM at the co-culture phase.The transformants still displayed high resistance to hygromycin B after subculture for five generations.A total of 10 randomly selected transformants were used for PCR verification using the specific primers designed for the hph gene,and the results revealed that an expected band of 500 bp was amplified from all of the 10 transformants.Moreover,PCR amplification for these 10 transformants was carried out using specific primers designed for the Vir gene of A.tumefaciens,with four strains of A.tumefaciens as positive controls for eliminating the false-positive caused by the contamination of A.tumefaciens.An expected band of 730 bp was amplified from the four strains of A.tumefaciens,whereas no corresponding DNA band could be amplified from the 10 transformants.The results of the two PCR amplifications clearly showed that T-DNA was indeed inserted into the genome of target isolate GD118.
文摘A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B / Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper resistance and yield traits. A linkage map consisting of 119 DNA markers and spanned for 1188 cM over the 12 rice chromosomes was constructed. Thirty-two chromosomal segment substitution lines were selected based on the percentage of Xieqingzao B allele at marker loci. These lines are of great potential for gene mapping and alien gene introgression.
基金the National Natural Science Foundation of China (30600385)the National Key Technology R&D Program of China (2004NZ0104)
文摘To identify the function of differential expression proteins in different leaves of rice seedlings extracted from 2- to 5-leaf stages, the leaf proteins at the seedling stage of hybrid rice Shanyou 63 were studied by using the approach of plant proteomics, and those proteins were separated with two-dimensional electrophoresis （2-DE） and then analyzed with an imagemaster 2D Elite 5.0. The results showed that the 41 protein spots were detected differential expression, of which 17 new protein spots appeared after the 3-leaf stage, including 9 special protein spots, which were only detected at the 3-leaf stage. Thirteen protein spots increased first and then decreased in expression abundance gradually and finally even disappeared. For the other 11 protein spots, 3 protein spots decreased, but 6 protein spots were opposite in expression abundance, however, 2 protein spots expressed in an irregular pattern after the 2-leaf stage. Of the 41 differential leaf proteins, 15 protein spots were identified by ESI-Q MS/MS and categorized into 4 groups of functions. The results indicated that proteins were the carriers of the functions in cells, but were significantly influenced by the changes in cell function or intercellular environment; hence, the reason that caused the proteomic changes as mentioned earlier might be related to the occurrence of tillers at the rice seedling stage after the 3-leaf stage.
基金supported by the National Natural Science Foundation of China(31601326)the National Transgenic Major Program of China(2016ZX08004001 and 2016ZX08011003)the China Postdoctoral Science Foundation(2016M591300)。
文摘Glyphosate-tolerant soybean is the most widely planted genetically modified crop worldwide. However, soybean remains recalcitrant to routine transformation because of the low infection efficiency of Agrobacterium to soybean and lack of useful selectable markers. In this study, several Agrobacterium strains and cell densities were compared by transient expression of the GUS gene. The results showed that Agrobacterium strain Ag10 at cell densities of OD_(600) of 0.6–0.9 yielded the highest infection efficiency in Agrobacterium-mediated soybean cotyledonary node transformation system. Meanwhile, a simple and rapid method was developed for identification of glyphosate tolerance in putative T_0 transgenic plants, consisting of spotting plantlets with 1 μL Roundup~?. The whole cycle of genetic transformation could be shortened to about 3 mon by highly efficient selection with glyphosate during the transformation process and application of the spot assay in putative T_0 transgenic plantlets. The transformation frequency ranged from 2.9 to 5.6%. This study provides an improved protocol for development and identification of glyphosate-tolerant transgenic soybeans.
