[Objective] This study aimed to reveal the effects of Aphelenchoides besseyi infection on different rice varieties（lines）.[Method] By field observation and indoor phenotypic investigation,four conventional japonica ...[Objective] This study aimed to reveal the effects of Aphelenchoides besseyi infection on different rice varieties（lines）.[Method] By field observation and indoor phenotypic investigation,four conventional japonica rice varieties（lines） and japonica rice restorer line R161 under natural onset conditions were observed and analyzed.[Result] After being infected by A.besseyi,different rice varieties（lines）exhibited various symptoms.Specifically,Ning 1707,Ning 1818,Zhendao 88 and Nanjing 9108 had withered leaf tips and exhibited the symptoms of ＂small grains and erect panicles＂;japonica rice restorer line R161 only had withered leaf tips without symptoms of ＂small grains and erect panicles＂,and the withering symptoms occurred in flag leaf tip,whole flag leaf and top second leaf,respectively.After being infected by A.besseyi,all the experimental materials could sprout normally,but their plant height,panicle length,seed-setting rate and 1 000-grain weight were affected to varying degrees.In addition,after being infected by A.besseyi,various symptomatic tissues of R161 exerted different effects on rice yield.Especially,panicles with withered and twisted whole flag leaf were most affected.[Conclusion] This study provided the basis for further exploration of the damages of A.besseyi infection to rice and development of corresponding control measures.展开更多
A population of 140 recombinant inbred lines at F8 generation were obtained after seven successive generations of self-pollination using single seed descent（SSD） method from the F2 hybrids of three-line restorers Lu...A population of 140 recombinant inbred lines at F8 generation were obtained after seven successive generations of self-pollination using single seed descent（SSD） method from the F2 hybrids of three-line restorers Luhui 8258 with high combining ability and Yanghui 34. Then, the 140 inbred lines obtained above and their parents Luhui 8258 and Yanghui 34 were crossed with three different types of cyto-plasmic male sterile（CMS） lines（Gang 46 A, Ⅱ-32 A and Lu 98A） according to NCⅡ design. The resulting 426 combinations were planted at Deyang and Suining bases to test the combining ability and inheritance of five yield traits： yield per plant, panicle number per plant, filled grain number per panicle, seed setting rate and 1 000-grain weight. The results showed that the variances of both general and specific combining abilities of the five traits all reached a significant or extremely significant level at the two sites. The broad and narrow heritability of the yield traits（except 1 000-grain weight whose broad and narrow heritability were both over70%） were all below 50% at the two experimental bases, suggesting that the four traits were easily subjected to environment influence. Very significant positive correlation of general combining ability was found between yield per plant and other traits except 1 000-grain weight. The general combining ability variance showed a normal distribution among the recombinant inbred lines at two sites, right in line with inheritance of quantitative traits. So, the genes controlling rice general combining ability can be targeted by QTL mapping.展开更多
This study was undertaken to dissect quantitative trait loci （QTLs） controlling yield traits on the short arm of rice chromosome 6. A residual heterozygous line that carries a heterozygous segment extending from RM5...This study was undertaken to dissect quantitative trait loci （QTLs） controlling yield traits on the short arm of rice chromosome 6. A residual heterozygous line that carries a heterozygous segment extending from RM587 to RM19784 on the short arm of rice chromosome 6 was selected from an F7 population of the indica rice cross Zhenshan 97B/Milyang 46. An F2：3 population consisting of 221 lines was derived and grown in two trial sites. Six yield traits including number of panicles per plant, number of filled grains per panicle, total number of spikelets per panicle, spikelet fertility, 1 000-grain weight, and grain yield per plant were measured. An SSR marker linkage map was constructed and employed to determine QTLs for yield traits with Windows QTL Cartographer 2.5. QTLs were detected in the target interval for all the traits analyzed except NP, with phenotypic variance explained by a single QTL ranging between 6.3% and 35.2%. Most of the QTLs for yield components acted as additive QTLs, while the three QTLs for grain yield had dominance degrees of 1.65, 0.84, and -0.42, respectively. It was indicated that three or more QTLs for yield traits were located in the target region. The genetic action mode, the direction of the QTL effect, and the magnitude of the QTL effect varied among different QTLs for a given trait, and among QTLs for different traits that were located in the same interval.展开更多
Grain yield and heading date are key factors determining the commercial potential of a rice variety. Mapping of quantitative trait loci （QTLs） in rice has been advanced from primary mapping to gene cloning, and head...Grain yield and heading date are key factors determining the commercial potential of a rice variety. Mapping of quantitative trait loci （QTLs） in rice has been advanced from primary mapping to gene cloning, and heading date and yield traits have always attracted the greatest attention. In this review, genomic distribution of QTLs for heading date detected in populations derived from intra-specific crosses of Asian cultivated rice （Oryza sativa） was summarized, and their relationship with the genetic control of yield traits was analyzed. The information could be useful in the identification of QTLs for heading date and yield traits that are promising for the improvement of rice varieties.展开更多
The study of yield traits can reveal the genetic architecture of grain yield for improving maize production.In this study, an association panel comprising 362 inbred lines and a recombinant inbred line population deri...The study of yield traits can reveal the genetic architecture of grain yield for improving maize production.In this study, an association panel comprising 362 inbred lines and a recombinant inbred line population derived from X178 × 9782 were used to identify candidate genes for nine yield traits. High-priority overlap(HPO) genes, which are genes prioritized in a genome-wide association study(GWAS), were investigated using coexpression networks. The GWAS identified 51 environmentally stable SNPs in two environments and 36 pleiotropic SNPs, including three SNPs with both attributes. Seven hotspots containing 41 trait-associated SNPs were identified on six chromosomes by permutation. Pyramiding of superior alleles showed a highly positive effect on all traits, and the phenotypic values of ear diameter and ear weight consistently corresponded with the number of superior alleles in tropical and temperate germplasm. A total of 61 HPO genes were detected after trait-associated SNPs were combined with the coexpression networks. Linkage mapping identified 16 environmentally stable and 16 pleiotropic QTL.Seven SNPs that were located in QTL intervals were assigned as consensus SNPs for the yield traits.Among the candidate genes predicted by our study, some genes were confirmed to function in seed development. The gene Zm00001 d016656 encoding a serine/threonine protein kinase was associated with five different traits across multiple environments. Some genes were uniquely expressed in specific tissues and at certain stages of seed development. These findings will provide genetic information and resources for molecular breeding of maize grain yield.展开更多
Three residual heterozygous lines (RHLs) carrying heterozygous segments in the intervals RM587–RM225, RM204–RM6119 and RM6119–RM402 on the short arm of rice chromosome 6, respectively, were selected from a rice pop...Three residual heterozygous lines (RHLs) carrying heterozygous segments in the intervals RM587–RM225, RM204–RM6119 and RM6119–RM402 on the short arm of rice chromosome 6, respectively, were selected from a rice population derived from an RHL for the interval RM587–RM402. Ten maternal homozygotes, 10 paternal homozygotes and 20 heterozygotes were selected from each of the F2 populations derived from the three RHLs. The three sets of near isogenic lines (NILs) were grown to detect the grain yield per plant, number of panicles per plant, number of filled grains per panicle and 1000-grain weight. With analysis on the phenotypic differences among the three genotype groups in each NIL set and those among overlapping chromosome segment substitution lines, three QTLs for number of filled grains per panicle and two QTLs for grain yield per plant were resolved. They were located in the intervals ranging from 0.66 Mb to 2.49 Mb. The additive effect was higher than the dominance effect at each locus. The allele for increasing the trait value was derived from the paternal parent at qNFGP6-1, and from the maternal alleles at other QTLs. Based on the present study, an approach for constructing new genetic resource to facilitate fine mapping of QTLs in rice was proposed.展开更多
A recombinant inbred line population derived from a super hybrid rice Xieyou 9308（Xieqingzao B/Zhonghui 9308） and its genetic linkage map were used to detect quantitative trait loci（QTLs） for rice yield traits und...A recombinant inbred line population derived from a super hybrid rice Xieyou 9308（Xieqingzao B/Zhonghui 9308） and its genetic linkage map were used to detect quantitative trait loci（QTLs） for rice yield traits under the low and normal nitrogen（N） levels. A total of 52 QTLs for yield traits distributed in 27 regions on 9 chromosomes were detected, with each QTL explaining 4.93%–26.73% of the phenotypic variation. Eleven QTLs were simultaneously detected under the two levels, and 30 different QTLs were detected under the two N levels, thereby suggesting that the genetic bases controlling rice growth under the low and normal N levels were different. QTLs for number of panicles per plant, number of spikelets per panicle, number of filled grains per panicle, and grain density per panicle under the two N levels were detected in the RM135–RM168 interval on chromosome 3. QTLs for number of spikelets per panicle and number of filled grains per panicle under the two N levels, as well as number of panicles per plant and grain density per panicle, under the low N level, were detected in the RM5556–RM310 interval on chromosome 8. The above described QTLs shared similar regions with previously reported QTLs for rice N recycling.展开更多
Two recombinant inbred line （RIL） populations, one derived from a cross between Zhongyouzao 8 （indica） and Toyonishiki （japonica） and the other from a cross between Qishanzhan （indica） and Akihikari （japonica...Two recombinant inbred line （RIL） populations, one derived from a cross between Zhongyouzao 8 （indica） and Toyonishiki （japonica） and the other from a cross between Qishanzhan （indica） and Akihikari （japonica）, were grown in Liaoning and Sichuan Provinces, China, to study the panicle type index （PTI, the ratio of a number of node position on panicle axis where the secondary branch with the most numerous secondary branch grains is located to the number of primary branches） and its relationships with subspecies characteristics and yield traits. With continuous distribution of PTI and numerous of lines with different PTIs in the progenies, indica-japonica hybridization could be a method for breeding cultivars with ideal panicle type. PTI was significantly influenced by environments, with a significant decrease from Liaoning to Sichuan A significantly negative correlation was found between PTI and most of subspecies characteristics. PTI varied remarkably with different subspecies types. As a whole, it showed a trend of indica （H）〉indicalinous （H＇）〉japonicalinous （K＇）〉japonica （K） However, it is not appropriate to regard PTI as a parameter for subspecies classification in rice because it was recombined in the filial generations of cross between indica and japonica rice. The negative correlations were found between PTI and most of panicle characteristics, as well as yield-related traits. Based on PTI, most of lines from the two populations were middle dominant panicle type （the number of grains on the secondary branch is numerous in middle position of the panicle） and lower dominant panicle type （the number of grains on the secondary branch is numerous in lower position of the panicle and becomes less towards the top of panicle） with significant yield advantages.展开更多
A genetic linkage map consisting of 168 DNA markers was constructed based on a recombinant inbred line(RID population derived from a cross between a high yielding indica variety, Zhong156, and a low yielding indica va...A genetic linkage map consisting of 168 DNA markers was constructed based on a recombinant inbred line(RID population derived from a cross between a high yielding indica variety, Zhong156, and a low yielding indica variety, Gumeil. The markers on the linkage map were distributed on all 12 chromosomes and covered 1 447. 9 cM of the genome. The parents and 304 RILs were grown in China National Rice Research Institute(CNRRI), Hangzhou, China, in 2001, over two seasons in a randomized block design. The statistic software of QTL Mapper 1.01 was applied to detect quantitative trait loci(QTLs)and additive by environment(AE)interactions for yield traits, including panicle length, number of panicles per plant, number of spikelets per panicle, number of filled grains per panicle, fertility and kilo-grain weight. A total of 30 QTLs with significant additive effects located on all chromosomes, except chromosomes 5 and 9, and two QTLs with significant AE interactions, were detected. Thirty-one interactions of QTLs showing significant additive by additive epistatic effects for yield traits were also detected. Genetic contributions were generally lower for QTLs showing epistatic effects compared with QTLs showing additive effects. No significant interactions between epistasis and environment were detected.展开更多
In flowering plants,the inflorescence meristem(IM)provides founder cells to form successive floral meristems,which are precursors of fruits and seeds.The activity and developmental progression of IM are thus critical ...In flowering plants,the inflorescence meristem(IM)provides founder cells to form successive floral meristems,which are precursors of fruits and seeds.The activity and developmental progression of IM are thus critical for yield production in seed crops.In some cereals,such as rice(Oryza sativa)and maize(Zea mays),the size of undifferentiated IM,which is located at the inflorescence apex,is positively associated with yield traits such as spikelet number.However,the relationship between IM size and yieldrelated spike traits remains unknown in the Triticeae tribe.Here we report that IM size has a negative correlation with yield traits in barley(Hordeum vulgare).Three FASCIATED EAR(FEA)orthologs,HvFEA2,HvFEA3,and HvFEA4,regulate IM size and spike morphogenesis and ultimately affect yield traits.Three HvFEAs genes are highly expressed in developing spikes,and all three loss-of-function mutants exhibit enlarged IM size,shortened spikes,and reduced spikelet number,which may lead to reduced grain yield.Natural variations identified in HvFEAs indicate selection events during barley domestication.We further reveal that HvFEA4,as a transcription factor,potentially targets multiple pathways during reproductive development,including transcriptional control,phytohormone signaling,and redox status.The roles of barley FEA genes in limiting IM size and promoting spikelet formation suggest the potential of increasing yield by manipulating IM activity.展开更多
QTLs for heading date located in the regions of Hd3a and Hd1 were detected using an F2:3 population developed from a residual heterozygous line(RHL) identified from the recombinant inbred lines of the indica rice cros...QTLs for heading date located in the regions of Hd3a and Hd1 were detected using an F2:3 population developed from a residual heterozygous line(RHL) identified from the recombinant inbred lines of the indica rice cross Zhenshan 97B /Milyang 46.Linkage in coupling phase between the QTLs for heading date and yield traits detected in a previous study was found.Four more F2:3 populations were each developed from an RHL that was homozygous at Hd3a and Hd1 but heterozygous in a portion of the intervals flanked by Hd3a and Hd1.QTLs for grain yield per plant,number of panicles per plant,number of grains per panicle and 1000-grain weight were detected in the heterozygous region.Five sets of near-isogenic lines(NILs) with overlapping heterogenous segments covering the interval RM6119-RM6779 were developed and used to validate and delimitate the QTLs.A QTL conferring a consistent effect for the number of grains per panicle was located within the interval RM19615-RM19652 that corresponded to a 514.4-kb region on chromosome 6.The same region might have pleiotropic effects on the other three yield-related traits analyzed,but the effects varied greatly among different populations and across different environments.This study suggests that it is possible to develop a population with little variation on heading date and to identify QTLs for yield traits that might not be associated with heading date by using the information of physical positions of DNA markers and cloned genes.展开更多
[Objectives]This study was conducted to provide a reliable theoretical basis for the correct formulation of breeding programs for red-seed watermelon and the effective breeding of hybrid offspring.[Methods]With local ...[Objectives]This study was conducted to provide a reliable theoretical basis for the correct formulation of breeding programs for red-seed watermelon and the effective breeding of hybrid offspring.[Methods]With local varieties and inbred lines of red-seed watermelon as test materials,the generalized heritability of fruit number per plant,single-fruit weight,single-fruit seed number,single-fruit seed weight,seed kernel weight,1000-seed weight,kernel-producing ratio,seed production ratio and seed volume were estimated by variance analysis;and the heritability,genetic variation coefficients,and correlation of the nine yield traits in 43 red-seed watermelon varieties were studied.[Results]The generalized heritability of fruit number per plant,single-fruit weight,single-fruit seed number,single-fruit seed weight,seed kernel weight,1000-seed weight,kernel-producing ratio,seed production ratio and seed volume were 12.86%,80.14%,75.96%,74.39%,48.01%,17.12%,24.97%,18.60%,and 37.07%,respectively.The heritability of single-fruit weight,single-fruit seed number and single-fruit seed weight was higher,and early-generation individual selection could achieve a better effect on them;and 1000-seed weight and kernel-producing ratio had a higher coefficient of genetic variation,indicating a high selection potential.[Conclusions]Indirect selection could be achieved for traits such as the single-fruit seed number,single-fruit seed weight,seed kernel weight,and seed volume by selecting the single-fruit weight.In the process of red-seed watermelon breeding,traits with high heritability can be selected in early generations of hybrids,thus playing the role of early-generation orientation.展开更多
The genetic distances among 18 cytoplasmic male sterile lines and 11 restorer lines were analyzed with molecular markers derived from yield-related functional genes. The correlation between parental genetic distance a...The genetic distances among 18 cytoplasmic male sterile lines and 11 restorer lines were analyzed with molecular markers derived from yield-related functional genes. The correlation between parental genetic distance and heterosis was investigated by analyzing the performance of 47 combinations. The results showed that the genetic distance was significantly correlated with yield heterosis （r=0.29^＊）, but not significantly correlated with heterosis for other traits, such as number of effective panicles per plant, seed setting rate, 1000-grain weight, number of grains per panicle and theoretical yield. However, the correlation coefficient was so small that the parental genetic distance could not to be used to predict heterosis.展开更多
Production of mutants with altered phenotypes is a powerful approach for determining the biological functions of genes in an organism. In this study, a high-grain-weight mutant line M8008 was identified from a library...Production of mutants with altered phenotypes is a powerful approach for determining the biological functions of genes in an organism. In this study, a high-grain-weight mutant line M8008 was identified from a library of mutants of the common wheat cultivar YN15 treated with ethylmethane sulfonate(EMS). F2 and F2:3generations produced from crosses of M8008 × YN15(MY) and M8008 × SJZ54(MS) were used for genetic analysis. There were significant differences between M8008 and YN15 in plant height(PH), spike length(SL),fertile spikelet number per spike(FSS), grain width(GW), grain length(GL), GL/GW ratio(GLW), and thousand-grain weight(TGW). Most simple correlation coefficients were significant for the investigated traits, suggesting that the correlative mutations occurred in M8008. Approximately 21% of simple sequence repeat(SSR) markers showed polymorphisms between M8008 and YN15, indicating that EMS can induce a large number of mutated loci. Twelve quantitative trait loci(QTLs) forming QTL clusters(one in MY and two in MS) were detected. The QTL clusters coinciding with(MY population) or near(MS population) the marker wmc41 were associated mainly with grain-size traits, among which the M8008 locus led to decreases in GW, factor form density(FFD), and TGW and to increases in GLW. The cluster in the wmc25–barc168 interval in the MS population was associated with yield traits, for which the M8008 locus led to decreased PH, spike number per plant(SN), and SL.展开更多
Seed priming is an effective seed pretreatment technology that enhances germination and overall crop performance by optimizing seed hydration and metabolic processes before planting.Seed quality is a critical determin...Seed priming is an effective seed pretreatment technology that enhances germination and overall crop performance by optimizing seed hydration and metabolic processes before planting.Seed quality is a critical determinant of cotton(Gossypium hirsutum)crop performance,influencing germination,plant vigor,and yield.This study evaluates the effects of seed priming with potassium salts(1%and 2%KCl and K2SO4)on germination,morphological traits,and Cry1Ac gene expression in three Bt cotton cultivars(IUB-2013,NIAB-878B,FH-142)as Cry1Ac enhance the pest resistance in Bt cotton and reduce the plant’s dependence on chemical insecticides.Seeds were primed for six hours,air-dried,and sown in the field.Germination rates,plant height,number of bolls per plant,boll weight,seed cotton yield,and ginning outturn(GOT)were assessed at crop maturity.Cry1Ac gene expression was quantified to explore the influence of priming treatments on transgene activity.Results demonstrated that 1%K2SO4 priming significantly enhanced germination and yield-related traits,with Cry1Ac expression peaking in the IUB-2013 cultivar under 1%K2SO4 treatment.These findings suggest that potassium-based halopriming improves cotton seedling establishment and Bt gene expression.This study addresses the critical gaps in understanding the effects of seed halopriming on morphological traits,germination,and expression of the Cry1Ac gene in Bt cotton while providing a novel eco-friendly and cost-effective halopriming approach,offering the potential to improve cotton production.展开更多
To screen high-quality early-maturing rapeseed germplasm resources,this study took six early-maturing Brassica napus varieties(ZY1,ZY2,ZY3,ZY4,ZY5,and ZY6)as research objects to compare and analyze their agronomic tra...To screen high-quality early-maturing rapeseed germplasm resources,this study took six early-maturing Brassica napus varieties(ZY1,ZY2,ZY3,ZY4,ZY5,and ZY6)as research objects to compare and analyze their agronomic traits,resistance,and yield traits.The results showed that the six early-maturing rapeseed varieties exhibited strong pre-winter growth,with the number of green leaf on the main stem ranging from 9.0 to 11.6,the total leaf number of main stem from 11.8 to 14.2,the maximum leaf length on main stem from 41.28 cm to 47.54 cm,the maximum leaf width from 12.02 cm to 13.38 cm,and the rhizome thickness from 20.64 mm to 25.82 mm.The order of green leaf,total leaf,maximum leaf length,and rhizome thickness from high to low across varieties was ZY1>ZY2>ZY3>ZY4>ZY5>ZY6,while the maximum leaf width followed ZY2>ZY1>ZY3>ZY4>ZY5>ZY6.Compared with other varieties,ZY1 and ZY2 had earlier bolting,initial flowering,final flowering,and harvesting times.The growth periods of the varieties were 183-189 d,with ZY1 being the shortest(183 d)and ZY2 following(185 d).Resistance investigations showed that ZY1 had the lowest freeze damage rate(13%)and freeze damage index(0.043),followed by ZY2(15%and 0.060).No Sclerotinia stem rot was observed at the seedling stage,while all varieties developed the disease at maturity;ZY1 had the lowest incidence(15%)and disease index(0.050),followed by ZY2(18%and 0.070).In terms of yield traits,the yield per plant of the six varieties ranged from 11.46 g to 14.53 g,with ZY1 being the highest(14.53 g)and ZY2 following(13.42 g).In conclusion,ZY1 and ZY2 exhibited vigorous pre-winter growth,early bolting and flowering,short growth periods,strong freeze and disease resistance,and high yield per plant,making them ideal materials for early-maturing rapeseed breeding.展开更多
Grass pea(Lathyrus sativus L.)is an imperative food crop cultured in dryland agricultural ecology.It is a vital source of dietary protein to millions of populaces living in low-income countries in South-East Asia and ...Grass pea(Lathyrus sativus L.)is an imperative food crop cultured in dryland agricultural ecology.It is a vital source of dietary protein to millions of populaces living in low-income countries in South-East Asia and Africa.This study highlights the improvement of genomic properties and their application in marker-trait relationships for 17 yield-related characters in 400 grass pea genotypes from China and Bangladesh.These characters were assessed via 56 polymorphic markers using general linear model(GLM)(P+G+Q)and mixed linear model(MLM)(P+G+Q+K)in the tassel software based on the linkage disequilibrium and population structure analysis.Population structure analysis showed two major groups and one admixed group in the populace.Statistically significant loci pairs of linkage disequilibrium(LD)mean value(D′)was 0.479.A total of 99 and 61 marker-trait associations in GLM and MLM models allied to the 17 traits were accepted at a 5%level of significance.Among these markers,21 markers were associated with more than one trait;12 marker-trait associations passed the Bonferroni correction threshold.Both models found six markers C41936,C39067,C34100,C47146,C47638,and C43047 significantly associated with days to maturity,flower color,plant height,and seed per pod were detected in the Hebei and Liaoyang location(p≤0.01),and the interpretation rate(R^(2)value)11.2%to 43.6%.Conferring to the consequences,the association analysis methodology may operative system for quantitative,qualitative,and biochemical traits related to gene position mapping and support breeders in improving novel approaches for advancing the grass pea quality.展开更多
Based on the results of the national regional trail for winter rapeseed in four groups,including the upper reaches,middle reaches and lower reaches of Yangtze River and Huang-Huai region in the past twenty years,new v...Based on the results of the national regional trail for winter rapeseed in four groups,including the upper reaches,middle reaches and lower reaches of Yangtze River and Huang-Huai region in the past twenty years,new varieties of winter rapeseed showed upward trend in average yield,the yield level in Huang-huai group was higher than other groups.The changes of average effective pods per plant were not significant in any group,but the number of grain per pod and 1 000-grain weight showed increase trend.However,the increment of grains per pod in three Yangtze River groups was higher than that in Huang-Huai River group,while the increment of 1 000-grain weight was just opposite.The incidence rate of Sclerotinia sclerotiorum and viral disease in new varieties of winter rapeseed obviously decreased,and the incidence rate of S.sclerotiorum decreased lower than 5%.Genetic improvement for winter rapeseed should be focus on the number of grain per pod and 1 000-grain weight in the future,and yield level of new varieties in all four groups is expected to increase.展开更多
In order to define the relationship between yield and important agronomic traits of two lines hybrid Uangyou 2111, the principal component analysis method was used to analyze the expadmental data of six test points in...In order to define the relationship between yield and important agronomic traits of two lines hybrid Uangyou 2111, the principal component analysis method was used to analyze the expadmental data of six test points in Yunnan Province. The results showed that the main factors influencing the production of Liangyou 2111 were grain number, grains seed number, panicle length, growth padod and panicle rate; then were 1 O00-grain weight, seed setting rate, effective panicle and highest stem tillers number; again was plant height. Therefore, when hybrid rice of Uangyou 2111 will be planted widely in yunnan province, we should focus on en- sudng the panicle traits, especially increase grain number and grain seed number, and coordinately develop other traits to achieve high yield.展开更多
Ethylene plays essential roles in adaptive growth of rice plants in water-saturating environment; how- ever, ethylene signaling pathway in rice is largely unclear. In this study, we report identification and character...Ethylene plays essential roles in adaptive growth of rice plants in water-saturating environment; how- ever, ethylene signaling pathway in rice is largely unclear. In this study, we report identification and characterization of ethylene-response mutants based on the specific ethylene-response phenotypes of etiolated rice seedlings, includ- ing ethylene-inhibited root growth and ethylene-promoted coleoptile elongation, which is different from the ethylene triple-response phenotype in Arabidopsis. We establish an efficient system for screening and a set of rice mutants have been identified. Genetic analysis reveals that these mutants form eight complementation groups. All the mutants show insensitivity or reduced sensitivity to ethylene in root growth but exhibit differential responses in cole0ptile growth. One mutant group mhz7 has insensitivity to ethylene in both root and coleoptile growth. We identified the corresponding gene by a map-based cloning method. MHZ7 encodes a membrane protein homologous to EIN2, a central component of ethylene signaling in Arabidopsis. Upon ethylene treatment, etiolated MHZ7-overexpressing seedlings exhibit enhanced coleoptiie elongation, increased mesocotyl growth and extremely twisted short roots, featuring enhanced ethylene- response phenotypes in rice. Grain length was promoted in MHZ7-transgenic plants and 1000-grain weight was reduced in mhz7 mutants. Leaf senescent process was also affected by MHZ7 expression. Manipulation of ethylene signaling may improve adaptive growth and yield-related traits in rice.展开更多
文摘[Objective] This study aimed to reveal the effects of Aphelenchoides besseyi infection on different rice varieties（lines）.[Method] By field observation and indoor phenotypic investigation,four conventional japonica rice varieties（lines） and japonica rice restorer line R161 under natural onset conditions were observed and analyzed.[Result] After being infected by A.besseyi,different rice varieties（lines）exhibited various symptoms.Specifically,Ning 1707,Ning 1818,Zhendao 88 and Nanjing 9108 had withered leaf tips and exhibited the symptoms of ＂small grains and erect panicles＂;japonica rice restorer line R161 only had withered leaf tips without symptoms of ＂small grains and erect panicles＂,and the withering symptoms occurred in flag leaf tip,whole flag leaf and top second leaf,respectively.After being infected by A.besseyi,all the experimental materials could sprout normally,but their plant height,panicle length,seed-setting rate and 1 000-grain weight were affected to varying degrees.In addition,after being infected by A.besseyi,various symptomatic tissues of R161 exerted different effects on rice yield.Especially,panicles with withered and twisted whole flag leaf were most affected.[Conclusion] This study provided the basis for further exploration of the damages of A.besseyi infection to rice and development of corresponding control measures.
基金Innovation Capacity Building Project of Supported by the Youth Fund of Innovation Capability Building Program of Sichuan Provincial Department of Finance(2014QNJJ-01)National High Technology Research and Development Program of China(2011AA10A101)Special Fund for Public Interest(Super Rice)from the Ministry of Agriculture of China(201100)~~
文摘A population of 140 recombinant inbred lines at F8 generation were obtained after seven successive generations of self-pollination using single seed descent（SSD） method from the F2 hybrids of three-line restorers Luhui 8258 with high combining ability and Yanghui 34. Then, the 140 inbred lines obtained above and their parents Luhui 8258 and Yanghui 34 were crossed with three different types of cyto-plasmic male sterile（CMS） lines（Gang 46 A, Ⅱ-32 A and Lu 98A） according to NCⅡ design. The resulting 426 combinations were planted at Deyang and Suining bases to test the combining ability and inheritance of five yield traits： yield per plant, panicle number per plant, filled grain number per panicle, seed setting rate and 1 000-grain weight. The results showed that the variances of both general and specific combining abilities of the five traits all reached a significant or extremely significant level at the two sites. The broad and narrow heritability of the yield traits（except 1 000-grain weight whose broad and narrow heritability were both over70%） were all below 50% at the two experimental bases, suggesting that the four traits were easily subjected to environment influence. Very significant positive correlation of general combining ability was found between yield per plant and other traits except 1 000-grain weight. The general combining ability variance showed a normal distribution among the recombinant inbred lines at two sites, right in line with inheritance of quantitative traits. So, the genes controlling rice general combining ability can be targeted by QTL mapping.
基金supported by the Zhejiang Natural Science Foundation(Y304446)the National 863 Program of China(2006AA10Z1E8)the Chinese Super Rice Breeding Program(200606).
文摘This study was undertaken to dissect quantitative trait loci （QTLs） controlling yield traits on the short arm of rice chromosome 6. A residual heterozygous line that carries a heterozygous segment extending from RM587 to RM19784 on the short arm of rice chromosome 6 was selected from an F7 population of the indica rice cross Zhenshan 97B/Milyang 46. An F2：3 population consisting of 221 lines was derived and grown in two trial sites. Six yield traits including number of panicles per plant, number of filled grains per panicle, total number of spikelets per panicle, spikelet fertility, 1 000-grain weight, and grain yield per plant were measured. An SSR marker linkage map was constructed and employed to determine QTLs for yield traits with Windows QTL Cartographer 2.5. QTLs were detected in the target interval for all the traits analyzed except NP, with phenotypic variance explained by a single QTL ranging between 6.3% and 35.2%. Most of the QTLs for yield components acted as additive QTLs, while the three QTLs for grain yield had dominance degrees of 1.65, 0.84, and -0.42, respectively. It was indicated that three or more QTLs for yield traits were located in the target region. The genetic action mode, the direction of the QTL effect, and the magnitude of the QTL effect varied among different QTLs for a given trait, and among QTLs for different traits that were located in the same interval.
基金funded by the Chinese High-Yielding Transgenic Program (Grant No. 2011ZX08001-004)the National High-Tech Research and Development Program (Grant No. 2011AA10A101)the Research Funding of China National Rice Research Institute(Grant No. 2009RG002)
文摘Grain yield and heading date are key factors determining the commercial potential of a rice variety. Mapping of quantitative trait loci （QTLs） in rice has been advanced from primary mapping to gene cloning, and heading date and yield traits have always attracted the greatest attention. In this review, genomic distribution of QTLs for heading date detected in populations derived from intra-specific crosses of Asian cultivated rice （Oryza sativa） was summarized, and their relationship with the genetic control of yield traits was analyzed. The information could be useful in the identification of QTLs for heading date and yield traits that are promising for the improvement of rice varieties.
基金funded and supported by China Agriculture Research System of MOF and MARA,Sichuan Science and Technology Support Project(2021YFYZ0020,2021YFYZ0027,2021YFFZ0017)National Natural Science Foundation of China(31971955)Sichuan Science and Technology Program(2019YJ0418,2020YJ0138)。
文摘The study of yield traits can reveal the genetic architecture of grain yield for improving maize production.In this study, an association panel comprising 362 inbred lines and a recombinant inbred line population derived from X178 × 9782 were used to identify candidate genes for nine yield traits. High-priority overlap(HPO) genes, which are genes prioritized in a genome-wide association study(GWAS), were investigated using coexpression networks. The GWAS identified 51 environmentally stable SNPs in two environments and 36 pleiotropic SNPs, including three SNPs with both attributes. Seven hotspots containing 41 trait-associated SNPs were identified on six chromosomes by permutation. Pyramiding of superior alleles showed a highly positive effect on all traits, and the phenotypic values of ear diameter and ear weight consistently corresponded with the number of superior alleles in tropical and temperate germplasm. A total of 61 HPO genes were detected after trait-associated SNPs were combined with the coexpression networks. Linkage mapping identified 16 environmentally stable and 16 pleiotropic QTL.Seven SNPs that were located in QTL intervals were assigned as consensus SNPs for the yield traits.Among the candidate genes predicted by our study, some genes were confirmed to function in seed development. The gene Zm00001 d016656 encoding a serine/threonine protein kinase was associated with five different traits across multiple environments. Some genes were uniquely expressed in specific tissues and at certain stages of seed development. These findings will provide genetic information and resources for molecular breeding of maize grain yield.
基金supported by the National High Technology Research and Development Program of China (Grant No. 2006AA10Z1E8)the Super Rice Program of Ministry of Agriculture, China (Grant No. 200606)the Natural Science Foundation of Zhejiang Province, China (Grant No. Y304446).
文摘Three residual heterozygous lines (RHLs) carrying heterozygous segments in the intervals RM587–RM225, RM204–RM6119 and RM6119–RM402 on the short arm of rice chromosome 6, respectively, were selected from a rice population derived from an RHL for the interval RM587–RM402. Ten maternal homozygotes, 10 paternal homozygotes and 20 heterozygotes were selected from each of the F2 populations derived from the three RHLs. The three sets of near isogenic lines (NILs) were grown to detect the grain yield per plant, number of panicles per plant, number of filled grains per panicle and 1000-grain weight. With analysis on the phenotypic differences among the three genotype groups in each NIL set and those among overlapping chromosome segment substitution lines, three QTLs for number of filled grains per panicle and two QTLs for grain yield per plant were resolved. They were located in the intervals ranging from 0.66 Mb to 2.49 Mb. The additive effect was higher than the dominance effect at each locus. The allele for increasing the trait value was derived from the paternal parent at qNFGP6-1, and from the maternal alleles at other QTLs. Based on the present study, an approach for constructing new genetic resource to facilitate fine mapping of QTLs in rice was proposed.
基金supported by the National Natural Science Foundation of China (Grant No. 31200916)the Zhejiang Provincial Project for Rice Seed Industry of Scientific and Technological Innovation Team (Grant No. 2010R50024-16)the Academy of Institute Foundation for Basic Scientific Research of China (Grant No. 2012RG002-7)
文摘A recombinant inbred line population derived from a super hybrid rice Xieyou 9308（Xieqingzao B/Zhonghui 9308） and its genetic linkage map were used to detect quantitative trait loci（QTLs） for rice yield traits under the low and normal nitrogen（N） levels. A total of 52 QTLs for yield traits distributed in 27 regions on 9 chromosomes were detected, with each QTL explaining 4.93%–26.73% of the phenotypic variation. Eleven QTLs were simultaneously detected under the two levels, and 30 different QTLs were detected under the two N levels, thereby suggesting that the genetic bases controlling rice growth under the low and normal N levels were different. QTLs for number of panicles per plant, number of spikelets per panicle, number of filled grains per panicle, and grain density per panicle under the two N levels were detected in the RM135–RM168 interval on chromosome 3. QTLs for number of spikelets per panicle and number of filled grains per panicle under the two N levels, as well as number of panicles per plant and grain density per panicle, under the low N level, were detected in the RM5556–RM310 interval on chromosome 8. The above described QTLs shared similar regions with previously reported QTLs for rice N recycling.
基金supported by the National Natural Science Foundation of China(GrantNo.30871468)the Young Teacher Scientific Research Fund of Shenyang Agricultural University,China(Grant No.20081001)
文摘Two recombinant inbred line （RIL） populations, one derived from a cross between Zhongyouzao 8 （indica） and Toyonishiki （japonica） and the other from a cross between Qishanzhan （indica） and Akihikari （japonica）, were grown in Liaoning and Sichuan Provinces, China, to study the panicle type index （PTI, the ratio of a number of node position on panicle axis where the secondary branch with the most numerous secondary branch grains is located to the number of primary branches） and its relationships with subspecies characteristics and yield traits. With continuous distribution of PTI and numerous of lines with different PTIs in the progenies, indica-japonica hybridization could be a method for breeding cultivars with ideal panicle type. PTI was significantly influenced by environments, with a significant decrease from Liaoning to Sichuan A significantly negative correlation was found between PTI and most of subspecies characteristics. PTI varied remarkably with different subspecies types. As a whole, it showed a trend of indica （H）〉indicalinous （H＇）〉japonicalinous （K＇）〉japonica （K） However, it is not appropriate to regard PTI as a parameter for subspecies classification in rice because it was recombined in the filial generations of cross between indica and japonica rice. The negative correlations were found between PTI and most of panicle characteristics, as well as yield-related traits. Based on PTI, most of lines from the two populations were middle dominant panicle type （the number of grains on the secondary branch is numerous in middle position of the panicle） and lower dominant panicle type （the number of grains on the secondary branch is numerous in lower position of the panicle and becomes less towards the top of panicle） with significant yield advantages.
基金supported by the Key Program of Zhejiang Province,China(010007015)the National 973 Program(2001CCA04100)the Open Program of the Key Laboratory for Rice Biology,Ministry of Agriculture,China.
文摘A genetic linkage map consisting of 168 DNA markers was constructed based on a recombinant inbred line(RID population derived from a cross between a high yielding indica variety, Zhong156, and a low yielding indica variety, Gumeil. The markers on the linkage map were distributed on all 12 chromosomes and covered 1 447. 9 cM of the genome. The parents and 304 RILs were grown in China National Rice Research Institute(CNRRI), Hangzhou, China, in 2001, over two seasons in a randomized block design. The statistic software of QTL Mapper 1.01 was applied to detect quantitative trait loci(QTLs)and additive by environment(AE)interactions for yield traits, including panicle length, number of panicles per plant, number of spikelets per panicle, number of filled grains per panicle, fertility and kilo-grain weight. A total of 30 QTLs with significant additive effects located on all chromosomes, except chromosomes 5 and 9, and two QTLs with significant AE interactions, were detected. Thirty-one interactions of QTLs showing significant additive by additive epistatic effects for yield traits were also detected. Genetic contributions were generally lower for QTLs showing epistatic effects compared with QTLs showing additive effects. No significant interactions between epistasis and environment were detected.
基金financially supported by the Science and Research Grant of Southwest University of Science and Technology(19zx7146)the start-up grant from Nanjing Agricultural University(to Gang Li)+2 种基金the Australia–China Science and Research Fund Joint Research Centre grant(ACSRF48187)the Australian Research Council(DP170103352)the Waite Research Institute(WRI)of the University of Adelaide。
文摘In flowering plants,the inflorescence meristem(IM)provides founder cells to form successive floral meristems,which are precursors of fruits and seeds.The activity and developmental progression of IM are thus critical for yield production in seed crops.In some cereals,such as rice(Oryza sativa)and maize(Zea mays),the size of undifferentiated IM,which is located at the inflorescence apex,is positively associated with yield traits such as spikelet number.However,the relationship between IM size and yieldrelated spike traits remains unknown in the Triticeae tribe.Here we report that IM size has a negative correlation with yield traits in barley(Hordeum vulgare).Three FASCIATED EAR(FEA)orthologs,HvFEA2,HvFEA3,and HvFEA4,regulate IM size and spike morphogenesis and ultimately affect yield traits.Three HvFEAs genes are highly expressed in developing spikes,and all three loss-of-function mutants exhibit enlarged IM size,shortened spikes,and reduced spikelet number,which may lead to reduced grain yield.Natural variations identified in HvFEAs indicate selection events during barley domestication.We further reveal that HvFEA4,as a transcription factor,potentially targets multiple pathways during reproductive development,including transcriptional control,phytohormone signaling,and redox status.The roles of barley FEA genes in limiting IM size and promoting spikelet formation suggest the potential of increasing yield by manipulating IM activity.
基金supported by the Chinese Super Rice Breeding Program(Grant No.200906)the National High Technology Research and Development Program(Grant No.2009AA101101)the Research Funding of the China National RiceResearch Institute(Grant No.2009RG002)
文摘QTLs for heading date located in the regions of Hd3a and Hd1 were detected using an F2:3 population developed from a residual heterozygous line(RHL) identified from the recombinant inbred lines of the indica rice cross Zhenshan 97B /Milyang 46.Linkage in coupling phase between the QTLs for heading date and yield traits detected in a previous study was found.Four more F2:3 populations were each developed from an RHL that was homozygous at Hd3a and Hd1 but heterozygous in a portion of the intervals flanked by Hd3a and Hd1.QTLs for grain yield per plant,number of panicles per plant,number of grains per panicle and 1000-grain weight were detected in the heterozygous region.Five sets of near-isogenic lines(NILs) with overlapping heterogenous segments covering the interval RM6119-RM6779 were developed and used to validate and delimitate the QTLs.A QTL conferring a consistent effect for the number of grains per panicle was located within the interval RM19615-RM19652 that corresponded to a 514.4-kb region on chromosome 6.The same region might have pleiotropic effects on the other three yield-related traits analyzed,but the effects varied greatly among different populations and across different environments.This study suggests that it is possible to develop a population with little variation on heading date and to identify QTLs for yield traits that might not be associated with heading date by using the information of physical positions of DNA markers and cloned genes.
基金Supported by"Watermelon and Muskmelon Germplasm Innovation and Genetic Improvement"Post of Guangxi Bagui Scholars(2016A11)。
文摘[Objectives]This study was conducted to provide a reliable theoretical basis for the correct formulation of breeding programs for red-seed watermelon and the effective breeding of hybrid offspring.[Methods]With local varieties and inbred lines of red-seed watermelon as test materials,the generalized heritability of fruit number per plant,single-fruit weight,single-fruit seed number,single-fruit seed weight,seed kernel weight,1000-seed weight,kernel-producing ratio,seed production ratio and seed volume were estimated by variance analysis;and the heritability,genetic variation coefficients,and correlation of the nine yield traits in 43 red-seed watermelon varieties were studied.[Results]The generalized heritability of fruit number per plant,single-fruit weight,single-fruit seed number,single-fruit seed weight,seed kernel weight,1000-seed weight,kernel-producing ratio,seed production ratio and seed volume were 12.86%,80.14%,75.96%,74.39%,48.01%,17.12%,24.97%,18.60%,and 37.07%,respectively.The heritability of single-fruit weight,single-fruit seed number and single-fruit seed weight was higher,and early-generation individual selection could achieve a better effect on them;and 1000-seed weight and kernel-producing ratio had a higher coefficient of genetic variation,indicating a high selection potential.[Conclusions]Indirect selection could be achieved for traits such as the single-fruit seed number,single-fruit seed weight,seed kernel weight,and seed volume by selecting the single-fruit weight.In the process of red-seed watermelon breeding,traits with high heritability can be selected in early generations of hybrids,thus playing the role of early-generation orientation.
基金supported by the National High Technology Research and Development of China(Grant No.2009AA101101)the China National Jumping Plan of Agricultural Technology and Science the Tackling Key Subject of Rice Breeding in Sichuan Province,China(Grant No.YZGG2006-1)the Youth Foundation of Sichuan Academy of Agricultural Sciences,China(Grant No.2008QNJJ)
文摘The genetic distances among 18 cytoplasmic male sterile lines and 11 restorer lines were analyzed with molecular markers derived from yield-related functional genes. The correlation between parental genetic distance and heterosis was investigated by analyzing the performance of 47 combinations. The results showed that the genetic distance was significantly correlated with yield heterosis （r=0.29^＊）, but not significantly correlated with heterosis for other traits, such as number of effective panicles per plant, seed setting rate, 1000-grain weight, number of grains per panicle and theoretical yield. However, the correlation coefficient was so small that the parental genetic distance could not to be used to predict heterosis.
基金supported by the National Natural Science Foundation of China (31271712)the National Key Technologies R&D Program of China (2013BAD01B02-8)
文摘Production of mutants with altered phenotypes is a powerful approach for determining the biological functions of genes in an organism. In this study, a high-grain-weight mutant line M8008 was identified from a library of mutants of the common wheat cultivar YN15 treated with ethylmethane sulfonate(EMS). F2 and F2:3generations produced from crosses of M8008 × YN15(MY) and M8008 × SJZ54(MS) were used for genetic analysis. There were significant differences between M8008 and YN15 in plant height(PH), spike length(SL),fertile spikelet number per spike(FSS), grain width(GW), grain length(GL), GL/GW ratio(GLW), and thousand-grain weight(TGW). Most simple correlation coefficients were significant for the investigated traits, suggesting that the correlative mutations occurred in M8008. Approximately 21% of simple sequence repeat(SSR) markers showed polymorphisms between M8008 and YN15, indicating that EMS can induce a large number of mutated loci. Twelve quantitative trait loci(QTLs) forming QTL clusters(one in MY and two in MS) were detected. The QTL clusters coinciding with(MY population) or near(MS population) the marker wmc41 were associated mainly with grain-size traits, among which the M8008 locus led to decreases in GW, factor form density(FFD), and TGW and to increases in GLW. The cluster in the wmc25–barc168 interval in the MS population was associated with yield traits, for which the M8008 locus led to decreased PH, spike number per plant(SN), and SL.
基金National Natural Science Foundation of China(3216045632360474+2 种基金32360486)grants from the Provincial Basic Research Program(Natural Science)([2020]1Z018)Provincial Key Technology R&D Program([2021]YiBan272).
文摘Seed priming is an effective seed pretreatment technology that enhances germination and overall crop performance by optimizing seed hydration and metabolic processes before planting.Seed quality is a critical determinant of cotton(Gossypium hirsutum)crop performance,influencing germination,plant vigor,and yield.This study evaluates the effects of seed priming with potassium salts(1%and 2%KCl and K2SO4)on germination,morphological traits,and Cry1Ac gene expression in three Bt cotton cultivars(IUB-2013,NIAB-878B,FH-142)as Cry1Ac enhance the pest resistance in Bt cotton and reduce the plant’s dependence on chemical insecticides.Seeds were primed for six hours,air-dried,and sown in the field.Germination rates,plant height,number of bolls per plant,boll weight,seed cotton yield,and ginning outturn(GOT)were assessed at crop maturity.Cry1Ac gene expression was quantified to explore the influence of priming treatments on transgene activity.Results demonstrated that 1%K2SO4 priming significantly enhanced germination and yield-related traits,with Cry1Ac expression peaking in the IUB-2013 cultivar under 1%K2SO4 treatment.These findings suggest that potassium-based halopriming improves cotton seedling establishment and Bt gene expression.This study addresses the critical gaps in understanding the effects of seed halopriming on morphological traits,germination,and expression of the Cry1Ac gene in Bt cotton while providing a novel eco-friendly and cost-effective halopriming approach,offering the potential to improve cotton production.
文摘To screen high-quality early-maturing rapeseed germplasm resources,this study took six early-maturing Brassica napus varieties(ZY1,ZY2,ZY3,ZY4,ZY5,and ZY6)as research objects to compare and analyze their agronomic traits,resistance,and yield traits.The results showed that the six early-maturing rapeseed varieties exhibited strong pre-winter growth,with the number of green leaf on the main stem ranging from 9.0 to 11.6,the total leaf number of main stem from 11.8 to 14.2,the maximum leaf length on main stem from 41.28 cm to 47.54 cm,the maximum leaf width from 12.02 cm to 13.38 cm,and the rhizome thickness from 20.64 mm to 25.82 mm.The order of green leaf,total leaf,maximum leaf length,and rhizome thickness from high to low across varieties was ZY1>ZY2>ZY3>ZY4>ZY5>ZY6,while the maximum leaf width followed ZY2>ZY1>ZY3>ZY4>ZY5>ZY6.Compared with other varieties,ZY1 and ZY2 had earlier bolting,initial flowering,final flowering,and harvesting times.The growth periods of the varieties were 183-189 d,with ZY1 being the shortest(183 d)and ZY2 following(185 d).Resistance investigations showed that ZY1 had the lowest freeze damage rate(13%)and freeze damage index(0.043),followed by ZY2(15%and 0.060).No Sclerotinia stem rot was observed at the seedling stage,while all varieties developed the disease at maturity;ZY1 had the lowest incidence(15%)and disease index(0.050),followed by ZY2(18%and 0.070).In terms of yield traits,the yield per plant of the six varieties ranged from 11.46 g to 14.53 g,with ZY1 being the highest(14.53 g)and ZY2 following(13.42 g).In conclusion,ZY1 and ZY2 exhibited vigorous pre-winter growth,early bolting and flowering,short growth periods,strong freeze and disease resistance,and high yield per plant,making them ideal materials for early-maturing rapeseed breeding.
基金the financial support from the Protection and Utilization of Crop Germplasm Resources project from the Ministry of Agriculture and Rural Affairs of China(2019NWB036-07)China Agriculture Research System of MOF and MARA-Food Legumes(CARS-08)+2 种基金National Infrastructure for Crop Germplasm Resources Project from the Ministry of Science and Technology of China(NICGR2019)Agricultural Science and Technology Innovation Program(ASTIP)in CAAS and Bangladesh-Second Phase of the National Agricultural Technology Program-Phase II Project,Bangladesh Agricultural Research Council(BARC),Bangladesh(P149553)supported by Researchers Supporting Project Number(RSP2025R7),King Saud University,Riyadh,Saudi Arabia.
文摘Grass pea(Lathyrus sativus L.)is an imperative food crop cultured in dryland agricultural ecology.It is a vital source of dietary protein to millions of populaces living in low-income countries in South-East Asia and Africa.This study highlights the improvement of genomic properties and their application in marker-trait relationships for 17 yield-related characters in 400 grass pea genotypes from China and Bangladesh.These characters were assessed via 56 polymorphic markers using general linear model(GLM)(P+G+Q)and mixed linear model(MLM)(P+G+Q+K)in the tassel software based on the linkage disequilibrium and population structure analysis.Population structure analysis showed two major groups and one admixed group in the populace.Statistically significant loci pairs of linkage disequilibrium(LD)mean value(D′)was 0.479.A total of 99 and 61 marker-trait associations in GLM and MLM models allied to the 17 traits were accepted at a 5%level of significance.Among these markers,21 markers were associated with more than one trait;12 marker-trait associations passed the Bonferroni correction threshold.Both models found six markers C41936,C39067,C34100,C47146,C47638,and C43047 significantly associated with days to maturity,flower color,plant height,and seed per pod were detected in the Hebei and Liaoyang location(p≤0.01),and the interpretation rate(R^(2)value)11.2%to 43.6%.Conferring to the consequences,the association analysis methodology may operative system for quantitative,qualitative,and biochemical traits related to gene position mapping and support breeders in improving novel approaches for advancing the grass pea quality.
文摘Based on the results of the national regional trail for winter rapeseed in four groups,including the upper reaches,middle reaches and lower reaches of Yangtze River and Huang-Huai region in the past twenty years,new varieties of winter rapeseed showed upward trend in average yield,the yield level in Huang-huai group was higher than other groups.The changes of average effective pods per plant were not significant in any group,but the number of grain per pod and 1 000-grain weight showed increase trend.However,the increment of grains per pod in three Yangtze River groups was higher than that in Huang-Huai River group,while the increment of 1 000-grain weight was just opposite.The incidence rate of Sclerotinia sclerotiorum and viral disease in new varieties of winter rapeseed obviously decreased,and the incidence rate of S.sclerotiorum decreased lower than 5%.Genetic improvement for winter rapeseed should be focus on the number of grain per pod and 1 000-grain weight in the future,and yield level of new varieties in all four groups is expected to increase.
基金Supported by Yunnan Agricultural Development BureauYunnan Modern Agricultural Rice Industry Technology System~~
文摘In order to define the relationship between yield and important agronomic traits of two lines hybrid Uangyou 2111, the principal component analysis method was used to analyze the expadmental data of six test points in Yunnan Province. The results showed that the main factors influencing the production of Liangyou 2111 were grain number, grains seed number, panicle length, growth padod and panicle rate; then were 1 O00-grain weight, seed setting rate, effective panicle and highest stem tillers number; again was plant height. Therefore, when hybrid rice of Uangyou 2111 will be planted widely in yunnan province, we should focus on en- sudng the panicle traits, especially increase grain number and grain seed number, and coordinately develop other traits to achieve high yield.
基金the National Natural Science Foundation of China，the National Key Basic Research Project，the National Transgenic Research Project
文摘Ethylene plays essential roles in adaptive growth of rice plants in water-saturating environment; how- ever, ethylene signaling pathway in rice is largely unclear. In this study, we report identification and characterization of ethylene-response mutants based on the specific ethylene-response phenotypes of etiolated rice seedlings, includ- ing ethylene-inhibited root growth and ethylene-promoted coleoptile elongation, which is different from the ethylene triple-response phenotype in Arabidopsis. We establish an efficient system for screening and a set of rice mutants have been identified. Genetic analysis reveals that these mutants form eight complementation groups. All the mutants show insensitivity or reduced sensitivity to ethylene in root growth but exhibit differential responses in cole0ptile growth. One mutant group mhz7 has insensitivity to ethylene in both root and coleoptile growth. We identified the corresponding gene by a map-based cloning method. MHZ7 encodes a membrane protein homologous to EIN2, a central component of ethylene signaling in Arabidopsis. Upon ethylene treatment, etiolated MHZ7-overexpressing seedlings exhibit enhanced coleoptiie elongation, increased mesocotyl growth and extremely twisted short roots, featuring enhanced ethylene- response phenotypes in rice. Grain length was promoted in MHZ7-transgenic plants and 1000-grain weight was reduced in mhz7 mutants. Leaf senescent process was also affected by MHZ7 expression. Manipulation of ethylene signaling may improve adaptive growth and yield-related traits in rice.
