Cultivated peanut (Arachis hypogaea) is an allotetraploid crop planted in Asia, Africa, and America for edible oil and protein. To explore the origins and consequences of tetraploidy, we sequenced the allotetraploid A...Cultivated peanut (Arachis hypogaea) is an allotetraploid crop planted in Asia, Africa, and America for edible oil and protein. To explore the origins and consequences of tetraploidy, we sequenced the allotetraploid A. hypogaea genome and compared it with the related diploid Arachis duranensis and Arachis ipaensis genomes. We annotated 39 888 A-subgenome genes and 41 526 B-subgenome genes in allotetraploid peanut. The A. hypogaea subgenomes have evolved asymmetrically, with the B subgenome resembling the ancestral state and the A subgenome undergoing more gene disruption, loss, conversion, and transposable element proliferation, and having reduced gene expression during seed development despite lacking genome-wide expression dominance. Genomic and transcriptomic analyses identified more than 2 500 oil metabolism-related genes and revealed that most of them show altered expression early in seed development while their expression ceases during desiccation, presenting a comprehensive map of peanut lipid biosynthesis. The availability of these genomic resources will facilitate a better understanding of the complex genome architecture, agronomically and economically important genes, and genetic improvement of peanut.展开更多
Flowering time and plant height are key agronomic traits that directly affect soybean(Glycine max)yield.APETALA1(AP1)functions as a class A gene in the ABCE model for floral organ development,helping to specify carpel...Flowering time and plant height are key agronomic traits that directly affect soybean(Glycine max)yield.APETALA1(AP1)functions as a class A gene in the ABCE model for floral organ development,helping to specify carpel,stamen,petal,and sepal identities.There are four AP1 homologs in soybean,all of which are mainly expressed in the shoot apex.Here,we used clustered regularly interspaced short palindromic repeats(CRISPR)–CRISPR-associated protein 9 technology to generate a homozygous quadruple mutant,gmap1,with loss-of-function mutations in all four GmAP1 genes.Under short-day(SD)conditions,the gmap1 quadruple mutant exhibited delayed flowering,changes in flower morphology,and increased node number and internode length,resulting in plants that were taller than the wild type.Conversely,overexpression of GmAP1a resulted in early flowering and reduced plant height compared to the wild type under SD conditions.The gmap1 mutant and the overexpression lines also exhibited altered expression of several genes related to flowering and gibberellic acid metabolism,thereby providing insight into the role of GmAP1 in the regulatory networks controlling flowering time and plant height in soybean.Increased node number is the trait with the most promise for enhancing soybean pod number and grain yield.Therefore,the mutant alleles of the four AP1 homologs described here will be invaluable for molecular breeding of improved soybean yield.展开更多
Genotyping platforms,as critical supports for genomics,genetics,and molecular breeding,have been well implemented at national institutions/universities in developed countries and multinational seed companies that poss...Genotyping platforms,as critical supports for genomics,genetics,and molecular breeding,have been well implemented at national institutions/universities in developed countries and multinational seed companies that possess high-throughput,automatic,large-scale,and shared facilities.In this study,we integrated an improved genotyping by target sequencing(GBTS)system with capture-in-solution(liquid chip)technology to develop a multiple single-nucleotide polymorphism(mSNP)approach in which mSNPs can be captured from a single amplicon.From one 40K maize mSNP panel,we developed three types of markers(40K mSNPs,251K SNPs,and 690K haplotypes),and generated multiple panels with various marker densities(1K–40K mSNPs)by sequencing at different depths.Comparative genetic diversity analysis was performed with genic versus intergenic markers and di-allelic SNPs versus non-typical SNPs.Compared with the one-amplicon-one-SNP system,mSNPs and within-mSNP haplotypes are more powerful for genetic diversity detection,linkage disequilibrium decay analysis,and genome-wide association studies.The technologies,protocols,and application scenarios developed for maize in this study will serve as a model for the development of mSNP arrays and highly efficient GBTS systems in animals,plants,and microorganisms.展开更多
The gene Fhb1 has been used in many countries to improve wheat Fusarium head blight(FHB) resistance. To make better use of this gene in the Yellow-Huai River Valleys Winter Wheat Zone(YHWZ), the most important wheat-p...The gene Fhb1 has been used in many countries to improve wheat Fusarium head blight(FHB) resistance. To make better use of this gene in the Yellow-Huai River Valleys Winter Wheat Zone(YHWZ), the most important wheat-producing region of China, it is desirable to elucidate its effects on FHB resistance and agronomic traits in different genetic backgrounds. Based on a diagnostic marker for Fhb1, six BC2 populations were developed by crossing dwarf-male-sterile(DMS)-Zhoumai 16 to three Fhb1 donors(Ningmai 9, Ningmai 13, and Jianyang 84) and backcrossing to Zhoumai 16 and Zhoumai16’s derivative cultivars(Lunxuan 136 and Lunxuan 13) using marker-assisted backcross breeding. The progenies were assessed for FHB resistance and major agronomic traits.The Fhb1 alleles were identified using the gene-specific molecular marker. The plants with the Fhb1-resistant genotype(Fhb1-R) in these populations showed significantly fewer infected spikelets than those with the Fhb1-susceptible genotype(Fhb1-S). When Lunxuan 136 was used as the recurrent parent, Fhb1-R plants showed significantly fewer infected spikelets per spike than Fhb1-R plants produced using Lunxuan 13 as the recurrent parent, indicating that the genetic backgrounds of Fhb1 influence the expression of FHB resistance. Fhb1-R plants from the DMS-Zhoumai 16/Ningmai 9//Zhoumai 16/3/Lunxuan 136 population showed the highest FHB resistance among the six populations and a significantly higher level of FHB resistance than the moderately susceptible control Huaimai 20. No significant phenotypic differences between Fhb1-R and Fhb1-S plants were observed for the eight agronomic traits investigated. These results suggest that it is feasible to improve FHB resistance of winter wheat withoutreducing yield potential by introgressing Fhb1 resistance allele into FHB-susceptible cultivars in the YHWZ.展开更多
Soybean(Glycine max)is an important and valuable crop,providing oil and proteins for both humans and animals.Seed weight is a key trait that determines soybean yields;however,the genes and mechanisms controlling seed ...Soybean(Glycine max)is an important and valuable crop,providing oil and proteins for both humans and animals.Seed weight is a key trait that determines soybean yields;however,the genes and mechanisms controlling seed weight remain poorly understood.Here,we used genome-wide association study(GWAS)and joint linkage mapping to identify a ubiquitin-specific protease,GmSW17.1,which regulates 100-seed weight in soybean.Two natural allelic variants of GmSW17.1 resulted in significantly different 100-seed weight,with GmSW17.1T conferring heavier seeds.We used CRISPR/Cas9 technology to knock out GmSW17.1,resulting in lighter and smaller seeds;however,these mutants produced more seeds than the wild type,resulting in similar overall yields.Owing to the increased number of seeds,we determined that GmSW17.1 is highly transcribed in developing seeds,and its encoded protein physically interacts in the nucleus with GmSGF11,which plays a crucial role in the deubiquitinating pathway.Analysis of genomic sequences from more than 1714 soybean accessions suggested that the natural allele GmSW17.1T was selected during the domestication and genetic improvement,resulting in its rapid expansion in cultivated soybean.These findings provide important insights into the role of GmSW17.1 in 100-seed weight and offer valuable clues for the molecular breeding of soybean.展开更多
Despite recent advances in crop metabolomics,the genetic control and molecular basis of the wheat kernel metabolome at different developmental stages remain largely unknown.Here,we performed widely tar-geted metabolit...Despite recent advances in crop metabolomics,the genetic control and molecular basis of the wheat kernel metabolome at different developmental stages remain largely unknown.Here,we performed widely tar-geted metabolite profiling of kernels from three developmental stages(grain-filling kernels[FKs],mature kernels[MKs],and germinating kernels[GKs])using a population of 159 recombinant inbred lines.We de-tected 625 annotated metabolites and mapped 3173,3143,and 2644 metabolite quantitative trait loci(mQTLs)in FKs,MKs,and GKs,respectively.Only 52 mQTLs were mapped at all three stages,indicating the high stage specificity of the wheat kernel metabolome.Four candidate genes were functionally vali-dated by in vitro enzymatic reactions and/or transgenic approaches in wheat,three of which mediated the tricin metabolic pathway.Metaboliteflux efficiencies within the tricin pathway were evaluated,and su-perior candidate haplotypes were identified,comprehensively delineating the tricin metabolism pathway in wheat.Finally,additional wheat metabolic pathways were re-constructed by updating them to incorporate the 177 candidate genes identified in this study.Our work provides new information on variations in the wheat kernel metabolome and important molecular resources for improvement of wheat nutritional quality.展开更多
Gene innovation plays an essential role in trait evolution.Rhizobial symbioses,the most important N2-fixing agent in agricultural systems that exists mainly in Leguminosae,is one of the most attractive evolution event...Gene innovation plays an essential role in trait evolution.Rhizobial symbioses,the most important N2-fixing agent in agricultural systems that exists mainly in Leguminosae,is one of the most attractive evolution events.However,the gene innovations underlying Leguminosae root nodule symbiosis(RNS)remain largely unknown.Here,we investigated the gene gain event in Leguminosae RNS evolution through comprehensive phylogenomic analyses.We revealed that Leguminosae-gain genes were acquired by gene duplication and underwent a strong purifying selection.Kyoto Encyclopedia of Genes and Genomes analyses showed that the innovated genes were enriched in flavonoid biosynthesis pathways,particular downstream of chalcone synthase(CHS).Among them,Leguminosae-gain typeⅡchalcone isomerase(CHI)could be further divided into CHI1A and CHI1B clades,which resulted from the products of tandem duplication.Furthermore,the duplicated CHI genes exhibited exon–intron structural divergences evolved through exon/intron gain/loss and insertion/deletion.Knocking down CHI1B significantly reduced nodulation in Glycine max(soybean)and Medicago truncatula;whereas,knocking down its duplication gene CHI1A had no effect on nodulation.Therefore,Leguminosae-gain typeⅡCHI participated in RNS and the duplicated CHI1A and CHI1B genes exhibited RNS functional divergence.This study provides functional insights into Leguminosae-gain genetic innovation and sub-functionalization after gene duplication that contribute to the evolution and adaptation of RNS in Leguminosae.展开更多
The aim was to explore the linear regression prediction models between sowing time and plant height, leaf stem ratio and DW/FW ratio of forage sorghum in autumn idle land. [Method] The relationships between sowing tim...The aim was to explore the linear regression prediction models between sowing time and plant height, leaf stem ratio and DW/FW ratio of forage sorghum in autumn idle land. [Method] The relationships between sowing time and plant height, leaf stem ratio and DW/FW ratio of forage sorghum were simulated and compared by employing field plot experiment and linear regression analysis. [Result] The sowing time had a great impact on plant height, leaf stem ratio and DW/FW ratio of forage sorghum in autumn idle land. With the delay of sowing time, the plant height and DW/FW ratio of forage sorghum decreased, while the leaf stem ratio increased. The regression models between sowing time and plant height, leaf stem ratio and DW/FW ratio of forage sorghum were established： plant height and sowing time, yheight = 234.725- 5.005X; leaf stem ratio and sowing time,ylcaf= 0.096 ＋ 0,019x; DW/FW ratio and sowing time, ydry= 0.305-0.002X. From July 23rd to August 30th, the plant height of forage sorghum was reduced by 5.005 cm, the leaf stem ratio was increased by 0.019 and the DW/FW ratio was reduced by 0.002 in average when hhe sowing time was delayed by one day. [Conclusion] This study provides a theoretical support for the production of forage sorghum in autumn idle land.展开更多
The shortage of groundwater resources is a considerable challenge for winter wheat production on the North China Plain.Water-saving technologies and procedures are thus urgently required.To determine the water-saving ...The shortage of groundwater resources is a considerable challenge for winter wheat production on the North China Plain.Water-saving technologies and procedures are thus urgently required.To determine the water-saving potential of using micro-sprinkling irrigation(MSI)for winter wheat production,field experiments were conducted from 2012 to 2015.Compared to traditional flooding irrigation(TFI),micro-sprinkling thrice with 90 mm water(MSI1)and micro-sprinkling four times with 120 mm water(MSI2)increased the water use efficiency by 22.5 and 16.2%,respectively,while reducing evapotranspiration by 17.6 and 10.8%.Regardless of the rainfall pattern,MSI(i.e.,MSI1 or MSI2)either stabilized or significantly increased the grain yield,while reducing irrigation water volumes by 20–40%,compared to TFI.Applying the same volumes of irrigation water,MSI(i.e.,MSI3,micro-sprinkling five times with 150 mm water)increased the grain yield and water use efficiency of winter wheat by 4.6 and 11.7%,respectively,compared to TFI.Because MSI could supply irrigation water more frequently in smaller amounts each time,it reduced soil layer compaction,and may have also resulted in a soil water deficit that promoted the spread of roots into the deep soil layer,which is beneficial to photosynthetic production in the critical period.In conclusion,MSI1 or MSI2 either stabilized or significantly increased grain yield while reducing irrigation water volumes by 20–40%compared to TFI,and should provide water-saving technological support in winter wheat production for smallholders on the North China Plain.展开更多
The growth periods（GPs, from planting/emergence to reproductive stage 8（R8） of soybean cultivars vary in different ecological regions, especially in China with a very complex soybean cropping system. In this study,...The growth periods（GPs, from planting/emergence to reproductive stage 8（R8） of soybean cultivars vary in different ecological regions, especially in China with a very complex soybean cropping system. In this study, a 3-yr experimental study was undertaken in three geographical locations of China from 2008 to 2010, including the Northeast（40.66-45.85°N）, Huang-Huai（34.75-38.04°N） and southern（22.82-30.60°N） eco-regions with about 250 accessions in each region to clarify the classification of maturity group（MG） and identify the cultivars with stable GP to increase the knowledge about the GP distribution of soybean cultivars in China. GPs of soybean cultivars in different eco-regions were significant different with a gradual decrease from 115-125 d in the Northeast part to the 85-100 d in the southern part of China. The geographical location was the major factor for GP of cultivars from the Northeast, while the year of planting was the major factor affecting the stability of GPs in Huang-Huai summer and southern summer soybean. AMMI2（additive main effects and multiplicativeinteraction）-Biplot analysis showed that the GPs of soybean cultivars from the Northeast eco-region have a comparatively satisfactory environmental stability. Moreover, soybean cultivars with moderate GP/MG and stable environment adaptability in different eco-regions were identified based on the linear regression and AMMI analysis, which was important for the accurate classification of soybean MGs in future. Taken together, our results reflected the genetic diversity, geographical distribution and environmental stability of the Chinese soybean GP trait. Soybean cultivars with stable GP for various Chinese eco-regions would be beneficial for Chinese soybean genetic improvement, varietal introduction, exchange, and soybean breeding program for wide adaptability.展开更多
Oilseed rape(Brassica napus) is an allotetraploid with two subgenomes descended from a common ancestor. Accordingly, its genome contains syntenic regions with many duplicate genes, some of which may have retained thei...Oilseed rape(Brassica napus) is an allotetraploid with two subgenomes descended from a common ancestor. Accordingly, its genome contains syntenic regions with many duplicate genes, some of which may have retained their original functions, whereas others may have diverged. Here, we mapped quantitative trait loci(QTL) for stem rot resistance(SRR), a disease caused by the fungus Sclerotinia sclerotiorum, and flowering time(FT) in a recombinant inbred line population. The population was genotyped using B.napus 60 K single nucleotide polymorphism arrays and phenotyped in six(FT) and nine(SSR) experimental conditions or environments. In total, we detected 30 SRR QTL and 22 FT QTL and show that some of the major QTL associated with these two traits were co-localized,suggesting a genetic linkage between them. Two SRR QTL on chromosome A2 and two on chromosome C2 were shown to be syntenic, suggesting the functional conservation of these regions. We used the syntenic properties of the genomic regions to exclude genes for selection candidates responsible for QTL-associated traits. For example, 152 of the 185 genes could be excluded from a syntenic A2–C2 region. These findings will help to elucidate polyploid genomics in future studies, in addition to providing useful information for B. napus breeding programs.展开更多
Foxtail millet(Setaria italica)growth was inhibited because of waterlogging stress,which has caused yield reduc-tion.ERF family plays an important role to plant adversity tolerance.In our study,we obtained 19,819 diff...Foxtail millet(Setaria italica)growth was inhibited because of waterlogging stress,which has caused yield reduc-tion.ERF family plays an important role to plant adversity tolerance.In our study,we obtained 19,819 differential expressed genes(DEGs)between the two treatments based on the RNA-seq sequencing of foxtail millet of water-logging stress.Furthermore,a total of 28 ERF family members were obtained,which have a complete open read-ing frame.We studied the evolution and function of SiERF family and how they affected the waterlogging tolerance.It was found that SiERF1A/B/C(GenBank ID:OR775217,OR775219,OR775218)and SiRAP2-12(GenBank ID:OR775216)have similar functions to the known waterlogging tolerance genes of other plants.Among them,the SiRAP2-12 expression was obviously significantly up-regulated in foxtail millet after 5d water-logging stress.After SiRAP2-12 was silenced,the activity of defense enzymes in millet decreased significantly.In details,superoxide dismutase(SOD),catalase(CAT)and peroxidase(POD),the osmotic regulator proline(Pro),and the activity of the anaerobic respiratory enzyme alcohol dehydrogenase(ADH)content were decreased by 78.61%,29.52%,79.95%,19.41%and 54.77%,respectively.In contrast,the relative electrical conductivity contents(REC),malondialdehyde(MDA),and hydrogen peroxide(H_(2)O_(2))of the foxtail millet subjected to virus-induced gene silencing clearly increased by 1.03-fold,36.09%,and 15.21%,respectively.The content of sodium(Na^(+))in the SiRAP2-12-silenced foxtail millet also increased,but that of potassium(K^(+))decreased.Interestingly,we found that ethylene content was significantly reduced.Further,the SiAOC1 expression,an essential gene for ethylene synthesis,was inhibited in SiRAP2-12-silenced foxtail millet after waterlogging stress.Taken together,we hypothesized that SiRAP2-12 might be a positive regulator of millet tolerance to waterlogging stress.展开更多
Nitrogen(N)is unevenly distributed throughout the soil and plant roots proliferate in N-rich soil patches.However,the relationship between the root response to localized N supply and maize N uptake efficiency among di...Nitrogen(N)is unevenly distributed throughout the soil and plant roots proliferate in N-rich soil patches.However,the relationship between the root response to localized N supply and maize N uptake efficiency among different genotypes is unclear.In this study,four maize varieties were evaluated to explore genotypic differences in the root response to local N application in relation to N uptake.A split-root system was established for hydroponically-grown plants and two methods of local N application(local banding and local dotting)were examined in the field.Genotypic differences in the root length response to N were highly correlated between the hydroponic and field conditions(r>0.99).Genotypes showing high response to N,ZD958,XY335 and XF32D22,showed 50‒63%longer lateral root length and 36‒53%greater root biomass in N-rich regions under hydroponic conditions,while the LY13 genotype did not respond to N.Under field conditions,the root length of the high-response genotypes was found to increase by 66‒75%at 40‒60 cm soil depth,while LY13 showed smaller changes in root length.In addition,local N application increased N uptake at the post-silking stage by 16‒88%in the high-response genotypes and increased the grain yield of ZD958 by 10‒12%.Moreover,yield was positively correlated with root length at 40‒60 cm soil depth(r=0.39).We conclude that local fertilization should be used for high-response genotypes,which can be rapidly identified at the seedling stage,and selection for“local-N responsive roots”can be a promising trait in maize breeding for high nitrogen uptake efficiency.展开更多
Root system architecture （RSA） plays an important role in phosphorus （P） acquisition, but enhancing P use efficiency （PUE） in maize via genetic manipulation of RSA has not yet been reported. Here, using a maize ...Root system architecture （RSA） plays an important role in phosphorus （P） acquisition, but enhancing P use efficiency （PUE） in maize via genetic manipulation of RSA has not yet been reported. Here, using a maize recombinant inbred line （RIL） population, we investigated the genetic relationships between PUE and RSA, and developed P-efficient lines by selection of quantitative trait loci （QTLs） that coincide for both traits. In low-P （LP） fields, P uptake efficiency （PupE） was more closely correlated with PUE （r = 0.48 -0.54）, and RSA in hydroponics was significantly related to PupE （r=0.25-0.30） but not to P utilization efficiency （PutE）. QTL analysis detected a chromosome region where two QTLs for PUE, three for PupE and three for RSA were assigned into two QTL clusters, Cl-bin3.04a and Cl-bin3.04b. These QTLs had favorable effects from alleles derived from the large-rooted and high-PupE parent. Marker-assisted selection （MAS） identified nine advanced backcross-derived lines carrying Cl-bin3.04a or Cl-bin3.04b that displayed mean increases of 22%-26% in PUE in LP fields. Furthermore, a line L224 pyramiding Cl- binB.04a and Cl-bin3.04b showed enhanced PupE, relying mainly on changes in root morphology, rather than root physiology, under both hydroponic and field conditions. These results highlight the physiological and genetic contributions of RSA to maize PupE, and provide a successful study case of developing P-efficient crops through QTL-based selection.展开更多
Mesocotyl elongation is a key trait influencing seedling emergence and establishment in direct-seeding rice cultivation.The phytohormone gibberellin(GA)has positive effects on mesocotyl elongation in rice.However,the ...Mesocotyl elongation is a key trait influencing seedling emergence and establishment in direct-seeding rice cultivation.The phytohormone gibberellin(GA)has positive effects on mesocotyl elongation in rice.However,the physiological and molecular basis underlying the regulation of mesocotyl elongation mediated by GA priming under deep-sowing conditions remains largely unclear.In the present study,we performed a physiological and comprehensive transcriptomic analysis of the function of GA priming in mesocotyl elongation and seedling emergence using a direct-seeding japonica rice cultivar ZH10 at a5-cm sowing depth.Physiological experiments indicated that GA priming significantly improved rice seedling emergence by increasing the activity of starch-metabolizing enzymes and compatible solute content to supply the energy essential for subsequent development.Transcriptomic analysis revealed 7074 differentially expressed genes(false discovery rate of<0.05,|log2(fold change)|of≥1)after GA priming.Furthermore,gene ontology(GO)and Kyoto encyclopedia of genes and genomes(KEGG)enrichment analyses revealed that genes associated with transcriptional regulation,plant hormone biosynthesis or signaling,and starch and sucrose metabolism were critical for GA-mediated promotion of rice mesocotyl elongation.Further analyses showed that the expression of the transcription factor(TF)genes(v-myb avian myeloblastosis viral oncogene homolog(MYB)alternative splicing 1(MYBAS1),phytochrome-interacting factors 1(PIF1),Oryza sativa teosinte branched 1/cycloidea/proliferating cell factor 5(Os TCP5),slender 1(SLN1),and mini zinc finger 1(MIF1)),plant hormone biosynthesis or signaling genes(brassinazole-resistant 1(BZR1),ent-kaurenoic acid oxidase-like(KAO),GRETCHEN HAGEN 3.2(GH3.2),and small auxin up RNA 36(SAUR36)),and starch and sucrose metabolism genes(α-amylases(AMY2 A and AMY1.4))was highly correlated with the mesocotyl elongation and deep-sowing tolerance response.These results enhance our understanding of how nutrient metabolism-related展开更多
Flowering time is an indicator of adaptation in maize and a key trait for selection in breeding.The genetic basis of flowering time in maize,especially in response to plant density,remains unclear.The objective of thi...Flowering time is an indicator of adaptation in maize and a key trait for selection in breeding.The genetic basis of flowering time in maize,especially in response to plant density,remains unclear.The objective of this study was to identify maize quantitative trait loci(QTL)associated with flowering time-related traits that are stably expressed under several plant densities and show additive effects that vary with plant density.Three hundred recombinant inbred lines(RIL)derived from a cross between Ye 478 and Qi 319,together with their parents,were planted at three plant densities(90,000,120,000,and 150,000 plants ha^(-1))in four environments.The five traits investigated were days to tasseling(DTT),days to silking(DTS),days to pollen shed(DTP),interval between anthesis and silking(ASI),and interval between tasseling and anthesis(TAI).A high-resolution bin map was used for QTL mapping.In the RIL population,the DTT,DTS,and DTP values increased with plant density,whereas the ASI and TAI values showed negligible response to plant density.A total of 72 QTL were identified for flowering time-related traits,including 15 stably expressed across environments.Maize flowering time under different densities seems to be regulated by complex pathways rather than by several major genes or an independent pathway.The effects of some stable QTL,especially qDTT8-1 and qDTT10-4,varied with plant density.Fine mapping and cloning of these QTL will shed light on the mechanism of flowering time and assist in breeding earlymaturing maize inbred lines and hybrids.展开更多
Field experiments were conducted at Cereal Crops Research Institute, Pirsabak, Nowshera, Pakistan, during winter 2003～2004; 2004～2005 to evaluate the effect of nitrogen; sulfur levels; methods of nitrogen applicatio...Field experiments were conducted at Cereal Crops Research Institute, Pirsabak, Nowshera, Pakistan, during winter 2003～2004; 2004～2005 to evaluate the effect of nitrogen; sulfur levels; methods of nitrogen application on canola (Brassica napus L. cv. Bulbul-98) under rainfed conditions. Four levels of S (0, 10, 20,; 30 kg/ha); three levels of N (40, 60,; 80 kg/ha); a control treatment with both nutrients at zero level were included in the experiments. Sulfur levels were applied at sowing while N levels were applied by three methods (100% soil application, 90% soil+10% foliar application,; 80% soil +20% foliar application). The experiments were laid out in randomized complete block (RCB) design having four replications. Oil content increased significantly up to 20 kg S/ha but further increase in S level did not enhance oil content. Glucosinolate content increased from 13.6 to 24.6 μmol/g as S rate was increased from 0 to 30 kg/ha. Protein content increased from 22.4% to 23.2% as S rate was increased from 0 to 20 kg/ha. Oil content responded negatively to the increasing N levels. The highest N level resulted in the highest values for protein (23.5%); glucosinolate (19.9 μmol/g) contents. Methods of N application had no significant impact on any parameters under study.展开更多
Although the use of heterosis in maize breeding has increased crop productivity,the genetic causes underlying heterosis for nitrogen(N) use efficiency(NUE) have been insufficiently investigated.In this study,five N-re...Although the use of heterosis in maize breeding has increased crop productivity,the genetic causes underlying heterosis for nitrogen(N) use efficiency(NUE) have been insufficiently investigated.In this study,five N-response traits and five low-N-tolerance traits were investigated using two inbred line populations(ILs) consisting of recombinant inbred lines(RIL) and advanced backcross(ABL) populations,derived from crossing Ye478 with Wu312.Both populations were crossed with P178 to construct two testcross populations.IL populations,their testcross populations,and the midparent heterosis(MPH)for NUE were investigated.Kernel weight,kernel number,and kernel number per row were sensitive to N level and ILs showed higher N response than did the testcross populations.Based on a highdensity linkage map,138 quantitative trait loci(QTL) were mapped,each explaining 5.6%–38.8% of genetic variation.There were 52,34 and 52 QTL for IL populations,MPH,and testcross populations,respectively.The finding that 7.6% of QTL were common to the ILs and their testcross populations and that 11.7% were common to the MPH and testcross population indicated that heterosis for NUE traits was regulated by non-additive and non-dominant loci.A QTL on chromosome 5 explained 27% of genetic variation in all of the traits and Gln1-3 was identified as a candidate gene for this QTL.Genome-wide prediction of NUE traits in the testcross populations showed 14%–51% accuracy.Our results may be useful for clarifying the genetic basis of heterosis for NUE traits and the candidate gene may be used for genetic improvement of maize NUE.展开更多
Since reform and open to the outside world,foxtail millet planting area in Hebei Province has constantly reduced,and its planting region has changed from the whole province into some regions,with obvious changes. In t...Since reform and open to the outside world,foxtail millet planting area in Hebei Province has constantly reduced,and its planting region has changed from the whole province into some regions,with obvious changes. In this paper,by using qualitative and quantitative approaches like chart analysis,summarizing,Delphi method and osculating value model,the influencing factors of changes in millet growing region in Hebei Province were studied. The results showed that the changes of millet planting area were closely related to many factors,such as little investment in scientific research,weak policy support,a single consumer product demand,the rapid development of other staple crops, labor migration,relatively low comparative effectiveness and physiological characteristics of the millet itself. Then some suggestions were put forward,such as increasing research support,strengthening scientific research strength,researching and developing deeply processed products, expanding consumer groups,improving millet policy support,providing subsidies for planting the improved varieties,researching and developing various types of machinery,and increasing millet production technology training.展开更多
Genomic prediction(GP)in plant breeding has the potential to predict and identify the best-performing hybrids based on the genotypes of their parental lines.In a GP experiment,34 elite inbred lines were selected to ma...Genomic prediction(GP)in plant breeding has the potential to predict and identify the best-performing hybrids based on the genotypes of their parental lines.In a GP experiment,34 elite inbred lines were selected to make 285 single-cross hybrids in a partial-diallel cross design.These lines represented a mini-core collection of Chinese maize germplasm and comprised 18 inbred lines from the Stiff Stalk heterotic group and 16 inbred lines from the Non-Stiff Stalk heterotic group.The parents were genotyped by sequencing and the 285 hybrids were phenotyped for nine yield and yield-related traits at two locations in the summer sowing area(SUS)and three locations in the spring sowing area(SPS)in the main maizeproducing regions of China.Multiple GP models were employed to assess the accuracy of trait prediction in the hybrids.By ten-fold cross-validation,the prediction accuracies of yield performance of the hybrids estimated by the genomic best linear unbiased prediction(GBLUP)model in SUS and SPS were 0.51 and 0.46,respectively.The prediction accuracies of the remaining yield-related traits estimated with GBLUP ranged from 0.49 to 0.86 and from 0.53 to 0.89 in SUS and SPS,respectively.When additive,dominance,epistasis effects,genotype-by-environment interaction,and multi-trait effects were incorporated into the prediction model,the prediction accuracy of hybrid yield performance was improved.The ratio of training to testing population and size of training population optimal for yield prediction were determined.Multiple prediction models can improve prediction accuracy in hybrid breeding.展开更多
基金National Natural Science Foundation of China (31501246,31771841,31801401)the Natural Science Foundation of Guangdong Province (2017A030311007)+4 种基金the Modem Agroindustry Technology Research System (CARS-14)the Science and Technology Planning Project of Guangdong Province (2015B020231006, 2015A020209051, 2016B020201003, 2016LM3161, 2016LM3164, 2014A020208060 and S2013020012647)the International Science & Technology Cooperation Program of Guangdong Province (2013B050800021)the Agricultural Science and Technology Program of Guangdong (2013B020301014)the teamwork projects funded Guangdong Natural Science Foundation of Guangdong Province (no. 2017A030312004).
文摘Cultivated peanut (Arachis hypogaea) is an allotetraploid crop planted in Asia, Africa, and America for edible oil and protein. To explore the origins and consequences of tetraploidy, we sequenced the allotetraploid A. hypogaea genome and compared it with the related diploid Arachis duranensis and Arachis ipaensis genomes. We annotated 39 888 A-subgenome genes and 41 526 B-subgenome genes in allotetraploid peanut. The A. hypogaea subgenomes have evolved asymmetrically, with the B subgenome resembling the ancestral state and the A subgenome undergoing more gene disruption, loss, conversion, and transposable element proliferation, and having reduced gene expression during seed development despite lacking genome-wide expression dominance. Genomic and transcriptomic analyses identified more than 2 500 oil metabolism-related genes and revealed that most of them show altered expression early in seed development while their expression ceases during desiccation, presenting a comprehensive map of peanut lipid biosynthesis. The availability of these genomic resources will facilitate a better understanding of the complex genome architecture, agronomically and economically important genes, and genetic improvement of peanut.
基金The authors would like to thank Professor YaoguangLiu at the South China Agricultural University forproviding the vector pYLCRISPR/Cas9P35SThiswork was supported by the National Naturalscience Foundation of China(31901499,31725021,31930083,31801384)This work was also funded bythe Major Program of Guangdong Basic and AppliedResearch(2019B030302006).
文摘Flowering time and plant height are key agronomic traits that directly affect soybean(Glycine max)yield.APETALA1(AP1)functions as a class A gene in the ABCE model for floral organ development,helping to specify carpel,stamen,petal,and sepal identities.There are four AP1 homologs in soybean,all of which are mainly expressed in the shoot apex.Here,we used clustered regularly interspaced short palindromic repeats(CRISPR)–CRISPR-associated protein 9 technology to generate a homozygous quadruple mutant,gmap1,with loss-of-function mutations in all four GmAP1 genes.Under short-day(SD)conditions,the gmap1 quadruple mutant exhibited delayed flowering,changes in flower morphology,and increased node number and internode length,resulting in plants that were taller than the wild type.Conversely,overexpression of GmAP1a resulted in early flowering and reduced plant height compared to the wild type under SD conditions.The gmap1 mutant and the overexpression lines also exhibited altered expression of several genes related to flowering and gibberellic acid metabolism,thereby providing insight into the role of GmAP1 in the regulatory networks controlling flowering time and plant height in soybean.Increased node number is the trait with the most promise for enhancing soybean pod number and grain yield.Therefore,the mutant alleles of the four AP1 homologs described here will be invaluable for molecular breeding of improved soybean yield.
基金This research is supported by the National Key Research and Development Program of China(2016YFD0101803 and 2017YFD0101201)the Central Public-interest Scientific Institution Basal Research Fund(Y2020PT20)+4 种基金the Agricultural Science and Technology Innovation Program(ASTIP)of the Chinese Academy of Agricultural Sciences(CAAS)(CAAS-XTCX2016009)the Key Research Area and Development Program of Guangdong Province(2018B020202008)the Shijiazhuang Science and Technology Incubation Program(191540089A)the Hebei Innovation Capability Enhancement Project(19962911D)Research activities at CIMMYT were supported by the Bill and Melinda Gates Foundation and the CGIAR Research Program MAIZE.
文摘Genotyping platforms,as critical supports for genomics,genetics,and molecular breeding,have been well implemented at national institutions/universities in developed countries and multinational seed companies that possess high-throughput,automatic,large-scale,and shared facilities.In this study,we integrated an improved genotyping by target sequencing(GBTS)system with capture-in-solution(liquid chip)technology to develop a multiple single-nucleotide polymorphism(mSNP)approach in which mSNPs can be captured from a single amplicon.From one 40K maize mSNP panel,we developed three types of markers(40K mSNPs,251K SNPs,and 690K haplotypes),and generated multiple panels with various marker densities(1K–40K mSNPs)by sequencing at different depths.Comparative genetic diversity analysis was performed with genic versus intergenic markers and di-allelic SNPs versus non-typical SNPs.Compared with the one-amplicon-one-SNP system,mSNPs and within-mSNP haplotypes are more powerful for genetic diversity detection,linkage disequilibrium decay analysis,and genome-wide association studies.The technologies,protocols,and application scenarios developed for maize in this study will serve as a model for the development of mSNP arrays and highly efficient GBTS systems in animals,plants,and microorganisms.
基金supported by the National Key Research and Development Program of China (2016YFD0101802, 2017YFD010060)the National Natural Science Foundation of China (31771881, 31401468)the Agricultural Science and Technology Innovation Program
文摘The gene Fhb1 has been used in many countries to improve wheat Fusarium head blight(FHB) resistance. To make better use of this gene in the Yellow-Huai River Valleys Winter Wheat Zone(YHWZ), the most important wheat-producing region of China, it is desirable to elucidate its effects on FHB resistance and agronomic traits in different genetic backgrounds. Based on a diagnostic marker for Fhb1, six BC2 populations were developed by crossing dwarf-male-sterile(DMS)-Zhoumai 16 to three Fhb1 donors(Ningmai 9, Ningmai 13, and Jianyang 84) and backcrossing to Zhoumai 16 and Zhoumai16’s derivative cultivars(Lunxuan 136 and Lunxuan 13) using marker-assisted backcross breeding. The progenies were assessed for FHB resistance and major agronomic traits.The Fhb1 alleles were identified using the gene-specific molecular marker. The plants with the Fhb1-resistant genotype(Fhb1-R) in these populations showed significantly fewer infected spikelets than those with the Fhb1-susceptible genotype(Fhb1-S). When Lunxuan 136 was used as the recurrent parent, Fhb1-R plants showed significantly fewer infected spikelets per spike than Fhb1-R plants produced using Lunxuan 13 as the recurrent parent, indicating that the genetic backgrounds of Fhb1 influence the expression of FHB resistance. Fhb1-R plants from the DMS-Zhoumai 16/Ningmai 9//Zhoumai 16/3/Lunxuan 136 population showed the highest FHB resistance among the six populations and a significantly higher level of FHB resistance than the moderately susceptible control Huaimai 20. No significant phenotypic differences between Fhb1-R and Fhb1-S plants were observed for the eight agronomic traits investigated. These results suggest that it is feasible to improve FHB resistance of winter wheat withoutreducing yield potential by introgressing Fhb1 resistance allele into FHB-susceptible cultivars in the YHWZ.
基金supported by Research and Application of Technological Innovation in Inner Mongolia Soybean Industry (2023DXZD0002)the National Natural Science Foundation of China (32201756)+4 种基金the National Key Research and Development Program of China (2021YFD1201600)the Agricultural Science and Technology Innovation Program (ASTIP)of Chinese Academy of Agricultural Sciences (CAAS-ZDRW202109,01-ICS-05)the earmarked fund for CARS (CARS-04-PS01)Scientific Innovation 2030 Project (2022ZD0401703)the National Science Foundation for Post-doctoral Scientists of China (2021 M703554).
文摘Soybean(Glycine max)is an important and valuable crop,providing oil and proteins for both humans and animals.Seed weight is a key trait that determines soybean yields;however,the genes and mechanisms controlling seed weight remain poorly understood.Here,we used genome-wide association study(GWAS)and joint linkage mapping to identify a ubiquitin-specific protease,GmSW17.1,which regulates 100-seed weight in soybean.Two natural allelic variants of GmSW17.1 resulted in significantly different 100-seed weight,with GmSW17.1T conferring heavier seeds.We used CRISPR/Cas9 technology to knock out GmSW17.1,resulting in lighter and smaller seeds;however,these mutants produced more seeds than the wild type,resulting in similar overall yields.Owing to the increased number of seeds,we determined that GmSW17.1 is highly transcribed in developing seeds,and its encoded protein physically interacts in the nucleus with GmSGF11,which plays a crucial role in the deubiquitinating pathway.Analysis of genomic sequences from more than 1714 soybean accessions suggested that the natural allele GmSW17.1T was selected during the domestication and genetic improvement,resulting in its rapid expansion in cultivated soybean.These findings provide important insights into the role of GmSW17.1 in 100-seed weight and offer valuable clues for the molecular breeding of soybean.
基金supported by the National Major Program of China (2023ZD0406903)the Natural Science Foundation for Distinguished Young Scientists of Hubei Province (2021CFA058)+2 种基金the Young Topnotch Talent Cultivation Program of Hubei Provincethe National Natural Science Foundation of China (32001541)the China Postdoctoral Science Foundation (2021T140246).
文摘Despite recent advances in crop metabolomics,the genetic control and molecular basis of the wheat kernel metabolome at different developmental stages remain largely unknown.Here,we performed widely tar-geted metabolite profiling of kernels from three developmental stages(grain-filling kernels[FKs],mature kernels[MKs],and germinating kernels[GKs])using a population of 159 recombinant inbred lines.We de-tected 625 annotated metabolites and mapped 3173,3143,and 2644 metabolite quantitative trait loci(mQTLs)in FKs,MKs,and GKs,respectively.Only 52 mQTLs were mapped at all three stages,indicating the high stage specificity of the wheat kernel metabolome.Four candidate genes were functionally vali-dated by in vitro enzymatic reactions and/or transgenic approaches in wheat,three of which mediated the tricin metabolic pathway.Metaboliteflux efficiencies within the tricin pathway were evaluated,and su-perior candidate haplotypes were identified,comprehensively delineating the tricin metabolism pathway in wheat.Finally,additional wheat metabolic pathways were re-constructed by updating them to incorporate the 177 candidate genes identified in this study.Our work provides new information on variations in the wheat kernel metabolome and important molecular resources for improvement of wheat nutritional quality.
基金The National Natural Science Foundation of China(grant nos.32388201,32300512 and U22A20467)“Strategic Priority Research Program”of the Chinese Academy of Sciences(grant no.XDA24030501)+1 种基金CAS Project for Young Scientists in Basic Research(YSBR-078)the Xplorer Prize。
文摘Gene innovation plays an essential role in trait evolution.Rhizobial symbioses,the most important N2-fixing agent in agricultural systems that exists mainly in Leguminosae,is one of the most attractive evolution events.However,the gene innovations underlying Leguminosae root nodule symbiosis(RNS)remain largely unknown.Here,we investigated the gene gain event in Leguminosae RNS evolution through comprehensive phylogenomic analyses.We revealed that Leguminosae-gain genes were acquired by gene duplication and underwent a strong purifying selection.Kyoto Encyclopedia of Genes and Genomes analyses showed that the innovated genes were enriched in flavonoid biosynthesis pathways,particular downstream of chalcone synthase(CHS).Among them,Leguminosae-gain typeⅡchalcone isomerase(CHI)could be further divided into CHI1A and CHI1B clades,which resulted from the products of tandem duplication.Furthermore,the duplicated CHI genes exhibited exon–intron structural divergences evolved through exon/intron gain/loss and insertion/deletion.Knocking down CHI1B significantly reduced nodulation in Glycine max(soybean)and Medicago truncatula;whereas,knocking down its duplication gene CHI1A had no effect on nodulation.Therefore,Leguminosae-gain typeⅡCHI participated in RNS and the duplicated CHI1A and CHI1B genes exhibited RNS functional divergence.This study provides functional insights into Leguminosae-gain genetic innovation and sub-functionalization after gene duplication that contribute to the evolution and adaptation of RNS in Leguminosae.
文摘The aim was to explore the linear regression prediction models between sowing time and plant height, leaf stem ratio and DW/FW ratio of forage sorghum in autumn idle land. [Method] The relationships between sowing time and plant height, leaf stem ratio and DW/FW ratio of forage sorghum were simulated and compared by employing field plot experiment and linear regression analysis. [Result] The sowing time had a great impact on plant height, leaf stem ratio and DW/FW ratio of forage sorghum in autumn idle land. With the delay of sowing time, the plant height and DW/FW ratio of forage sorghum decreased, while the leaf stem ratio increased. The regression models between sowing time and plant height, leaf stem ratio and DW/FW ratio of forage sorghum were established： plant height and sowing time, yheight = 234.725- 5.005X; leaf stem ratio and sowing time,ylcaf= 0.096 ＋ 0,019x; DW/FW ratio and sowing time, ydry= 0.305-0.002X. From July 23rd to August 30th, the plant height of forage sorghum was reduced by 5.005 cm, the leaf stem ratio was increased by 0.019 and the DW/FW ratio was reduced by 0.002 in average when hhe sowing time was delayed by one day. [Conclusion] This study provides a theoretical support for the production of forage sorghum in autumn idle land.
基金the National Key Research and Development Program of China(2017YFD0300203 and 2016YFD0300105)。
文摘The shortage of groundwater resources is a considerable challenge for winter wheat production on the North China Plain.Water-saving technologies and procedures are thus urgently required.To determine the water-saving potential of using micro-sprinkling irrigation(MSI)for winter wheat production,field experiments were conducted from 2012 to 2015.Compared to traditional flooding irrigation(TFI),micro-sprinkling thrice with 90 mm water(MSI1)and micro-sprinkling four times with 120 mm water(MSI2)increased the water use efficiency by 22.5 and 16.2%,respectively,while reducing evapotranspiration by 17.6 and 10.8%.Regardless of the rainfall pattern,MSI(i.e.,MSI1 or MSI2)either stabilized or significantly increased the grain yield,while reducing irrigation water volumes by 20–40%,compared to TFI.Applying the same volumes of irrigation water,MSI(i.e.,MSI3,micro-sprinkling five times with 150 mm water)increased the grain yield and water use efficiency of winter wheat by 4.6 and 11.7%,respectively,compared to TFI.Because MSI could supply irrigation water more frequently in smaller amounts each time,it reduced soil layer compaction,and may have also resulted in a soil water deficit that promoted the spread of roots into the deep soil layer,which is beneficial to photosynthetic production in the critical period.In conclusion,MSI1 or MSI2 either stabilized or significantly increased grain yield while reducing irrigation water volumes by 20–40%compared to TFI,and should provide water-saving technological support in winter wheat production for smallholders on the North China Plain.
基金supported by the Program of Accurate Identification and Display of Soybean Germplasm, China (NB08-2130315-(25-31)-06, NB07-2130315-(25-30)-06, NB06-070401-(22-27)-05), NB2010-2130315-25-05)the National Crop Germplasm Platform, Ministry of Agriculture and Ministry of Science and Technology, China (2012-004, 2014-004)
文摘The growth periods（GPs, from planting/emergence to reproductive stage 8（R8） of soybean cultivars vary in different ecological regions, especially in China with a very complex soybean cropping system. In this study, a 3-yr experimental study was undertaken in three geographical locations of China from 2008 to 2010, including the Northeast（40.66-45.85°N）, Huang-Huai（34.75-38.04°N） and southern（22.82-30.60°N） eco-regions with about 250 accessions in each region to clarify the classification of maturity group（MG） and identify the cultivars with stable GP to increase the knowledge about the GP distribution of soybean cultivars in China. GPs of soybean cultivars in different eco-regions were significant different with a gradual decrease from 115-125 d in the Northeast part to the 85-100 d in the southern part of China. The geographical location was the major factor for GP of cultivars from the Northeast, while the year of planting was the major factor affecting the stability of GPs in Huang-Huai summer and southern summer soybean. AMMI2（additive main effects and multiplicativeinteraction）-Biplot analysis showed that the GPs of soybean cultivars from the Northeast eco-region have a comparatively satisfactory environmental stability. Moreover, soybean cultivars with moderate GP/MG and stable environment adaptability in different eco-regions were identified based on the linear regression and AMMI analysis, which was important for the accurate classification of soybean MGs in future. Taken together, our results reflected the genetic diversity, geographical distribution and environmental stability of the Chinese soybean GP trait. Soybean cultivars with stable GP for various Chinese eco-regions would be beneficial for Chinese soybean genetic improvement, varietal introduction, exchange, and soybean breeding program for wide adaptability.
基金financially supported by the National Key Research and Development Program of China(2016YFD0100602,2016YFD0101007,2016YFD0100305)the National Natural Science Foundation of China(31471536 and 31770250)+1 种基金the China Agriculture Research System(CARS-1305)the Agricultural Science and Technology Innovation Program(ASTIP)of the National High Technology Research and Development Program of China(2013AA102602)
文摘Oilseed rape(Brassica napus) is an allotetraploid with two subgenomes descended from a common ancestor. Accordingly, its genome contains syntenic regions with many duplicate genes, some of which may have retained their original functions, whereas others may have diverged. Here, we mapped quantitative trait loci(QTL) for stem rot resistance(SRR), a disease caused by the fungus Sclerotinia sclerotiorum, and flowering time(FT) in a recombinant inbred line population. The population was genotyped using B.napus 60 K single nucleotide polymorphism arrays and phenotyped in six(FT) and nine(SSR) experimental conditions or environments. In total, we detected 30 SRR QTL and 22 FT QTL and show that some of the major QTL associated with these two traits were co-localized,suggesting a genetic linkage between them. Two SRR QTL on chromosome A2 and two on chromosome C2 were shown to be syntenic, suggesting the functional conservation of these regions. We used the syntenic properties of the genomic regions to exclude genes for selection candidates responsible for QTL-associated traits. For example, 152 of the 185 genes could be excluded from a syntenic A2–C2 region. These findings will help to elucidate polyploid genomics in future studies, in addition to providing useful information for B. napus breeding programs.
基金This research was supported by the China Agricultural Research System(CARS-06-14.5-A23)HAAFS Basic Science and Technology Contract Project(Grant No.HBNKY-BGZ-02)Technical System of Foxtail Millet Industry in Hebei Province.
文摘Foxtail millet(Setaria italica)growth was inhibited because of waterlogging stress,which has caused yield reduc-tion.ERF family plays an important role to plant adversity tolerance.In our study,we obtained 19,819 differential expressed genes(DEGs)between the two treatments based on the RNA-seq sequencing of foxtail millet of water-logging stress.Furthermore,a total of 28 ERF family members were obtained,which have a complete open read-ing frame.We studied the evolution and function of SiERF family and how they affected the waterlogging tolerance.It was found that SiERF1A/B/C(GenBank ID:OR775217,OR775219,OR775218)and SiRAP2-12(GenBank ID:OR775216)have similar functions to the known waterlogging tolerance genes of other plants.Among them,the SiRAP2-12 expression was obviously significantly up-regulated in foxtail millet after 5d water-logging stress.After SiRAP2-12 was silenced,the activity of defense enzymes in millet decreased significantly.In details,superoxide dismutase(SOD),catalase(CAT)and peroxidase(POD),the osmotic regulator proline(Pro),and the activity of the anaerobic respiratory enzyme alcohol dehydrogenase(ADH)content were decreased by 78.61%,29.52%,79.95%,19.41%and 54.77%,respectively.In contrast,the relative electrical conductivity contents(REC),malondialdehyde(MDA),and hydrogen peroxide(H_(2)O_(2))of the foxtail millet subjected to virus-induced gene silencing clearly increased by 1.03-fold,36.09%,and 15.21%,respectively.The content of sodium(Na^(+))in the SiRAP2-12-silenced foxtail millet also increased,but that of potassium(K^(+))decreased.Interestingly,we found that ethylene content was significantly reduced.Further,the SiAOC1 expression,an essential gene for ethylene synthesis,was inhibited in SiRAP2-12-silenced foxtail millet after waterlogging stress.Taken together,we hypothesized that SiRAP2-12 might be a positive regulator of millet tolerance to waterlogging stress.
基金supported by the Hainan Provincial Natural Science Foundation of China(321CXTD443)the National Natural Science Foundation of China(31972485 and 31971948).
文摘Nitrogen(N)is unevenly distributed throughout the soil and plant roots proliferate in N-rich soil patches.However,the relationship between the root response to localized N supply and maize N uptake efficiency among different genotypes is unclear.In this study,four maize varieties were evaluated to explore genotypic differences in the root response to local N application in relation to N uptake.A split-root system was established for hydroponically-grown plants and two methods of local N application(local banding and local dotting)were examined in the field.Genotypic differences in the root length response to N were highly correlated between the hydroponic and field conditions(r>0.99).Genotypes showing high response to N,ZD958,XY335 and XF32D22,showed 50‒63%longer lateral root length and 36‒53%greater root biomass in N-rich regions under hydroponic conditions,while the LY13 genotype did not respond to N.Under field conditions,the root length of the high-response genotypes was found to increase by 66‒75%at 40‒60 cm soil depth,while LY13 showed smaller changes in root length.In addition,local N application increased N uptake at the post-silking stage by 16‒88%in the high-response genotypes and increased the grain yield of ZD958 by 10‒12%.Moreover,yield was positively correlated with root length at 40‒60 cm soil depth(r=0.39).We conclude that local fertilization should be used for high-response genotypes,which can be rapidly identified at the seedling stage,and selection for“local-N responsive roots”can be a promising trait in maize breeding for high nitrogen uptake efficiency.
基金financially supported by the National Key Research and Development Program of China(No.2016YFD0100700)the National Science Foundation of China(Nos.31572186 and 31421092)
文摘Root system architecture （RSA） plays an important role in phosphorus （P） acquisition, but enhancing P use efficiency （PUE） in maize via genetic manipulation of RSA has not yet been reported. Here, using a maize recombinant inbred line （RIL） population, we investigated the genetic relationships between PUE and RSA, and developed P-efficient lines by selection of quantitative trait loci （QTLs） that coincide for both traits. In low-P （LP） fields, P uptake efficiency （PupE） was more closely correlated with PUE （r = 0.48 -0.54）, and RSA in hydroponics was significantly related to PupE （r=0.25-0.30） but not to P utilization efficiency （PutE）. QTL analysis detected a chromosome region where two QTLs for PUE, three for PupE and three for RSA were assigned into two QTL clusters, Cl-bin3.04a and Cl-bin3.04b. These QTLs had favorable effects from alleles derived from the large-rooted and high-PupE parent. Marker-assisted selection （MAS） identified nine advanced backcross-derived lines carrying Cl-bin3.04a or Cl-bin3.04b that displayed mean increases of 22%-26% in PUE in LP fields. Furthermore, a line L224 pyramiding Cl- binB.04a and Cl-bin3.04b showed enhanced PupE, relying mainly on changes in root morphology, rather than root physiology, under both hydroponic and field conditions. These results highlight the physiological and genetic contributions of RSA to maize PupE, and provide a successful study case of developing P-efficient crops through QTL-based selection.
基金supported by the National Key Research and Development Program of China(No.2016YFD0100101-19)the Rice Industry Technology System of Henan Province(No.S2012-04)the Independent Innovation Fund Program of Henan Academy of Agricultural Sciences(No.2020ZC07)。
文摘Mesocotyl elongation is a key trait influencing seedling emergence and establishment in direct-seeding rice cultivation.The phytohormone gibberellin(GA)has positive effects on mesocotyl elongation in rice.However,the physiological and molecular basis underlying the regulation of mesocotyl elongation mediated by GA priming under deep-sowing conditions remains largely unclear.In the present study,we performed a physiological and comprehensive transcriptomic analysis of the function of GA priming in mesocotyl elongation and seedling emergence using a direct-seeding japonica rice cultivar ZH10 at a5-cm sowing depth.Physiological experiments indicated that GA priming significantly improved rice seedling emergence by increasing the activity of starch-metabolizing enzymes and compatible solute content to supply the energy essential for subsequent development.Transcriptomic analysis revealed 7074 differentially expressed genes(false discovery rate of<0.05,|log2(fold change)|of≥1)after GA priming.Furthermore,gene ontology(GO)and Kyoto encyclopedia of genes and genomes(KEGG)enrichment analyses revealed that genes associated with transcriptional regulation,plant hormone biosynthesis or signaling,and starch and sucrose metabolism were critical for GA-mediated promotion of rice mesocotyl elongation.Further analyses showed that the expression of the transcription factor(TF)genes(v-myb avian myeloblastosis viral oncogene homolog(MYB)alternative splicing 1(MYBAS1),phytochrome-interacting factors 1(PIF1),Oryza sativa teosinte branched 1/cycloidea/proliferating cell factor 5(Os TCP5),slender 1(SLN1),and mini zinc finger 1(MIF1)),plant hormone biosynthesis or signaling genes(brassinazole-resistant 1(BZR1),ent-kaurenoic acid oxidase-like(KAO),GRETCHEN HAGEN 3.2(GH3.2),and small auxin up RNA 36(SAUR36)),and starch and sucrose metabolism genes(α-amylases(AMY2 A and AMY1.4))was highly correlated with the mesocotyl elongation and deep-sowing tolerance response.These results enhance our understanding of how nutrient metabolism-related
基金This study was supported by Hebei Province Special Postdoctoral Financial Assistance(B2017003030)the Youth Innovation Fund of the Institute of Cereal and Oil Crops,Hebei Academy of Agriculture and Forestry Sciences(LYS2017001)the Hebei Financial Special Project:Construction of Talents Team for Agricultural Science Technical Innovation,and the China Agriculture Research System(CARS-02).
文摘Flowering time is an indicator of adaptation in maize and a key trait for selection in breeding.The genetic basis of flowering time in maize,especially in response to plant density,remains unclear.The objective of this study was to identify maize quantitative trait loci(QTL)associated with flowering time-related traits that are stably expressed under several plant densities and show additive effects that vary with plant density.Three hundred recombinant inbred lines(RIL)derived from a cross between Ye 478 and Qi 319,together with their parents,were planted at three plant densities(90,000,120,000,and 150,000 plants ha^(-1))in four environments.The five traits investigated were days to tasseling(DTT),days to silking(DTS),days to pollen shed(DTP),interval between anthesis and silking(ASI),and interval between tasseling and anthesis(TAI).A high-resolution bin map was used for QTL mapping.In the RIL population,the DTT,DTS,and DTP values increased with plant density,whereas the ASI and TAI values showed negligible response to plant density.A total of 72 QTL were identified for flowering time-related traits,including 15 stably expressed across environments.Maize flowering time under different densities seems to be regulated by complex pathways rather than by several major genes or an independent pathway.The effects of some stable QTL,especially qDTT8-1 and qDTT10-4,varied with plant density.Fine mapping and cloning of these QTL will shed light on the mechanism of flowering time and assist in breeding earlymaturing maize inbred lines and hybrids.
基金the Higher Education Commission (HEC) of Pakistan
文摘Field experiments were conducted at Cereal Crops Research Institute, Pirsabak, Nowshera, Pakistan, during winter 2003～2004; 2004～2005 to evaluate the effect of nitrogen; sulfur levels; methods of nitrogen application on canola (Brassica napus L. cv. Bulbul-98) under rainfed conditions. Four levels of S (0, 10, 20,; 30 kg/ha); three levels of N (40, 60,; 80 kg/ha); a control treatment with both nutrients at zero level were included in the experiments. Sulfur levels were applied at sowing while N levels were applied by three methods (100% soil application, 90% soil+10% foliar application,; 80% soil +20% foliar application). The experiments were laid out in randomized complete block (RCB) design having four replications. Oil content increased significantly up to 20 kg S/ha but further increase in S level did not enhance oil content. Glucosinolate content increased from 13.6 to 24.6 μmol/g as S rate was increased from 0 to 30 kg/ha. Protein content increased from 22.4% to 23.2% as S rate was increased from 0 to 20 kg/ha. Oil content responded negatively to the increasing N levels. The highest N level resulted in the highest values for protein (23.5%); glucosinolate (19.9 μmol/g) contents. Methods of N application had no significant impact on any parameters under study.
基金financially supported by the National Key Research and Development Program of China (2021YFD1200700)the National Natural Science Foundation of China (31972485,31971948)the Hainan Provincial Science and Technology Plan Sanya Yazhou Bay Science and Technology City Joint Project(320LH011)。
文摘Although the use of heterosis in maize breeding has increased crop productivity,the genetic causes underlying heterosis for nitrogen(N) use efficiency(NUE) have been insufficiently investigated.In this study,five N-response traits and five low-N-tolerance traits were investigated using two inbred line populations(ILs) consisting of recombinant inbred lines(RIL) and advanced backcross(ABL) populations,derived from crossing Ye478 with Wu312.Both populations were crossed with P178 to construct two testcross populations.IL populations,their testcross populations,and the midparent heterosis(MPH)for NUE were investigated.Kernel weight,kernel number,and kernel number per row were sensitive to N level and ILs showed higher N response than did the testcross populations.Based on a highdensity linkage map,138 quantitative trait loci(QTL) were mapped,each explaining 5.6%–38.8% of genetic variation.There were 52,34 and 52 QTL for IL populations,MPH,and testcross populations,respectively.The finding that 7.6% of QTL were common to the ILs and their testcross populations and that 11.7% were common to the MPH and testcross population indicated that heterosis for NUE traits was regulated by non-additive and non-dominant loci.A QTL on chromosome 5 explained 27% of genetic variation in all of the traits and Gln1-3 was identified as a candidate gene for this QTL.Genome-wide prediction of NUE traits in the testcross populations showed 14%–51% accuracy.Our results may be useful for clarifying the genetic basis of heterosis for NUE traits and the candidate gene may be used for genetic improvement of maize NUE.
基金Supported by the Special Funds for Modern Agricultural Industrial Technology System of the Ministry of Agriculture and Ministry of Finance(CARS-07-12.5-A18)Funds for Young Scholars of Hebei Academy of Agriculture and Forestry Sciences"Study on the Changes of Millet Planting Area in Hebei Province Development Countermeasures"(A11030103)Subject of Hebei Academy of Agriculture and Forestry Sciences"Study on the Development Mode of Milletin Mountainous Areas"(A2012030106)
文摘Since reform and open to the outside world,foxtail millet planting area in Hebei Province has constantly reduced,and its planting region has changed from the whole province into some regions,with obvious changes. In this paper,by using qualitative and quantitative approaches like chart analysis,summarizing,Delphi method and osculating value model,the influencing factors of changes in millet growing region in Hebei Province were studied. The results showed that the changes of millet planting area were closely related to many factors,such as little investment in scientific research,weak policy support,a single consumer product demand,the rapid development of other staple crops, labor migration,relatively low comparative effectiveness and physiological characteristics of the millet itself. Then some suggestions were put forward,such as increasing research support,strengthening scientific research strength,researching and developing deeply processed products, expanding consumer groups,improving millet policy support,providing subsidies for planting the improved varieties,researching and developing various types of machinery,and increasing millet production technology training.
基金the National Natural Science Foundation of China(32272049,32261143757)Sustainable Development International Cooperation Program from Bill&Melinda Gates Foundation(2022YFAG1002)+2 种基金the National Key Research and Development Program of China(2020YFE0202300)the Agricultural Science&Technology Innovation Program(CAASZDRW202109)the China Scholarship Council.
文摘Genomic prediction(GP)in plant breeding has the potential to predict and identify the best-performing hybrids based on the genotypes of their parental lines.In a GP experiment,34 elite inbred lines were selected to make 285 single-cross hybrids in a partial-diallel cross design.These lines represented a mini-core collection of Chinese maize germplasm and comprised 18 inbred lines from the Stiff Stalk heterotic group and 16 inbred lines from the Non-Stiff Stalk heterotic group.The parents were genotyped by sequencing and the 285 hybrids were phenotyped for nine yield and yield-related traits at two locations in the summer sowing area(SUS)and three locations in the spring sowing area(SPS)in the main maizeproducing regions of China.Multiple GP models were employed to assess the accuracy of trait prediction in the hybrids.By ten-fold cross-validation,the prediction accuracies of yield performance of the hybrids estimated by the genomic best linear unbiased prediction(GBLUP)model in SUS and SPS were 0.51 and 0.46,respectively.The prediction accuracies of the remaining yield-related traits estimated with GBLUP ranged from 0.49 to 0.86 and from 0.53 to 0.89 in SUS and SPS,respectively.When additive,dominance,epistasis effects,genotype-by-environment interaction,and multi-trait effects were incorporated into the prediction model,the prediction accuracy of hybrid yield performance was improved.The ratio of training to testing population and size of training population optimal for yield prediction were determined.Multiple prediction models can improve prediction accuracy in hybrid breeding.
