One of the most important objectives for breeders is to develop high-yield cultivars.The increase in crop yield has met with bottlenecks after the first green revolution,and more recent efforts have been focusing on a...One of the most important objectives for breeders is to develop high-yield cultivars.The increase in crop yield has met with bottlenecks after the first green revolution,and more recent efforts have been focusing on achieving high photosynthetic efficiency traits in order to enhance the yield.Leaf shape is a significant agronomic trait of upland cotton that affects plant and canopy architecture,yield,and other production attributes.The major leaf shape types,including normal,sub-okra,okra,and super-okra,with varying levels of lobe severity,are controlled by a multiple allelic series of the D-genome locus L-D_(1).To analyze the effects of L-D_(1)alleles on leaf morphology,photosynthetic related traits and yield of cotton,two sets of near isogenic lines(NILs)with different alleles were constructed in Lumianyan 22(LMY22)and Lumianyan 28(LMY28)backgrounds.The analysis of morphological parameters and the results of virus-induced gene silencing(VIGS)showed that the regulation of leaf shape by L-D_(1)alleles was similar to a gene-dosage effect.Compared with the normal leaf,deeper lobes of the sub-okra leaf improved plant canopy structure by decreasing the leaf area index(LAI)and increasing the light transmittance rate(LTR),and the mid-range LAI of sub-okra leaf also guaranteed the accumulation of cotton biomass.Although the chlorophyll content(SPAD)of sub-okra leaf was lower than those of the other two leaf shapes,the net photosynthetic rate(Pn)of sub-okra leaf was higher than those of okra leaf and normal leaf at most stages.Thus,the improvements in canopy structure,as well as photosynthetic and physiological characteristics,contributed to optimizing the light environment,thereby increasing the total biomass and yield in the lines with a sub-okra leaf shape.Our results suggest that the sub-okra leaf may have practical application in cultivating varieties,and could enhance sustainable and profitable cotton production.展开更多
Straw return is a promising strategy for managing soil organic carbon(SOC)and improving yield stability.However,the optimal straw return strategy for sustainable crop production in the wheat(Triticum aestivum L.)-cott...Straw return is a promising strategy for managing soil organic carbon(SOC)and improving yield stability.However,the optimal straw return strategy for sustainable crop production in the wheat(Triticum aestivum L.)-cotton(Gossypium hirsutum L.)cropping system remains uncertain.The objective of this study was to quantify the long-term(10 years)impact of carbon(C)input on SOC sequestration,soil aggregation and crop yields in a wheat-cotton cropping system in the Yangtze River Valley,China.Five treatments were arranged with a single-factor randomized design as follows:no straw return(Control),return of wheat straw only(Wt),return of cotton straw only(Ct),return of 50%wheat and 50%cotton straw(Wh-Ch)and return of 100%wheat and 100%cotton straw(Wt-Ct).In comparison to the Control,the SOC content increased by 8.4 to 20.2%under straw return.A significant linear positive correlation between SOC sequestration and C input(1.42-7.19 Mg ha^(−1)yr^(−1))(P<0.05)was detected.The percentages of aggregates of sizes>2 and 1-2 mm at the 0-20 cm soil depth were also significantly elevated under straw return,with the greatest increase of the aggregate stability in the Wt-Ct treatment(28.1%).The average wheat yields increased by 12.4-36.0%and cotton yields increased by 29.4-73.7%,and significantly linear positive correlations were also detected between C input and the yields of wheat and cotton.The average sustainable yield index(SYI)reached a maximum value of 0.69 when the C input was 7.08 Mg ha^(−1)yr^(−1),which was close to the maximum value(SYI of 0.69,C input of 7.19 Mg ha^(−1)yr^(-1))in the Wt-Ct treatment.Overall,the return of both wheat and cotton straw was the best strategy for improving SOC sequestration,soil aggregation,yields and their sustainability in the wheat-cotton rotation system.展开更多
Rapeseed is a very important oil crop in China;however,its production is challenging due to the absence of effective weed management strategies.This is predominantly because of a shortage of herbicide resistance genes...Rapeseed is a very important oil crop in China;however,its production is challenging due to the absence of effective weed management strategies.This is predominantly because of a shortage of herbicide resistance genes.Acetohydroxyacid synthase(AHAS) herbicides inhibit AHAS,a key enzyme involved in branched-chain amino acid synthesis that is required for plant growth.A rapeseed line designated M342 with AHAS herbicide resistance was developed through seed mutagenesis and was studied to assess the level and mode of inheritance of the resistance and to identify the molecular basis of resistance.M342 possessed a high level of cross-resistance to sulfonylureas(SUs) and imidazolinones(IMIs).This resistance was due to AHAS insensitivity to these herbicides and was inherited as a dominant trait conferred by a single nuclear-encoded gene.Molecular analysis revealed the presence of a Trp574 Leu mutation in M342,and an allele-specific cleaved amplified polymorphic sequence(AS-CAPS) marker was developed and cosegregated with herbicide resistance in the F2,BC1,and BC2 populations.This mutation altered the transcript levels of Bn AHAS1 and Bn AHAS3 in M342 compared with those in the wild type,but it did not affect the agronomic or quality traits.The simple genetic inheritance of this mutation and the availability of the cleaved amplified polymorphic sequence(CAPS) marker and herbicide resistance gene should facilitate the development of herbicide-resistant rapeseed cultivars for effective weed control in China.展开更多
In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to g...In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to governmental organizations in charge of cultivar registration. Where competition among breeding companies exists, effective and fair multi-environment variety trials are of utmost importance to motivate investment in breeding. The objective of this study was to use genotype main effect plus genotype by environment interaction(GGE) biplot analysis to evaluate test locations in terms of discrimination ability, representativeness and desirability, and to investigate the presence of multiple mega-environments in cotton production in the Yangtze River Valley(YaRV), China. Four traits(cotton lint yield, fiber length, lint breaking tenacity, micronaire) and two composite selection indices were considered. It was found that the assumption of a single mega-environment in the YaRV for cotton production does not hold. The YaRV consists of three cotton mega-environments: a main one represented by 11 locations and two minor ones represented by two test locations each. This demands that the strategy of cotton variety registration or recommendation must be adjusted. GGE biplot analysis has also led to the identification of test location superior for cotton variety evaluation. Although test location desirable for selecting different traits varied greatly, Jinzhou, Hubei Province, China, was found to be desirable for selecting for all traits considered while Jianyang, Sichuan Province, China, was found to be desirable for none.展开更多
Influences of PGR, sucrose, and ammonium nitrate on in vitro flowering and fruiting from cotyledon explants of P.frutescens were studied. The regenerated shoots at 2-4 cm from cotyledon explants on MS medium supplemen...Influences of PGR, sucrose, and ammonium nitrate on in vitro flowering and fruiting from cotyledon explants of P.frutescens were studied. The regenerated shoots at 2-4 cm from cotyledon explants on MS medium supplemented with0.5 mg L-1 BA and 1.0 mg L-1 IAA were excised and transferred to MS medium containing 30 g L-1 sucrose, 8.25 g L-1ammonium nitrate, and 1.0 mg L-1 BA. Following 40 d of culture, 86.2% of them flowered and set seeds. These seeds weregerminable and developed into flowering plants in the fields. This study provides a simple system for rapid breeding ofP. frutescens and studying the physiological mechanism of flowering of plants.展开更多
The ascomycete fungus Colletotrichum gloeosporioides is a devastating plant pathogen with a wide host range and worldwide distribution. Carbendazim has been widely used to control anthracnose caused by the C. gloeospo...The ascomycete fungus Colletotrichum gloeosporioides is a devastating plant pathogen with a wide host range and worldwide distribution. Carbendazim has been widely used to control anthracnose caused by the C. gloeosporioides complex in China for more than 30 years and resistance to carbendazim has been reported in China. A total of 125 Colletotrichum isolates of strawberry and yam were collected from different geographical regions in Hubei Province, China. Approximately 52.8% of Colletotrichum spp. isolates showed resistance to carbendazim. The isolates tested in this study belong to four species, and the frequencies of resistant isolates differed across Colletotrichum species. Resistant isolates were found in C. siamense and C. fructicola. In contrast, all isolates of C. gloeosporioides and C. aenigma were sensitive to carbendazim. Highly carbendazim-resistant isolates harbored the E198 A mutation in the β-tubulin 2(TUB2) gene, whereas moderately carbendazim-resistant isolates harbored the F200 Y mutation in the TUB2 gene. Carbendazim-sensitive Colletotrichum isolates in this study were not genetically similar enough to form a separate cluster from resistant isolates. The result of this study emphasizes the importance of knowing which Colletotrichum sp. is present, when strategies for disease control are made.展开更多
Salt stress is one of the major abiotic stresses affecting soybean growth. Genetic improvement for salt tolerance is an effective way to protect soybean yield under salt stress conditions. Successful improvement of sa...Salt stress is one of the major abiotic stresses affecting soybean growth. Genetic improvement for salt tolerance is an effective way to protect soybean yield under salt stress conditions. Successful improvement of salt tolerance in soybean relies on identifying genetic variation that confers tolerance in soybean germplasm and subsequently incorporating these genetic resources into cultivars. In this review, we summarize the progress in genetic diversity and genetics of salt tolerance in soybean, which includes identifying genetic diversity for salt tolerant germplasm; mapping QTLs conferring salt tolerance; map-based cloning; and conducting genome-wide association study(GWAS) analysis in soybean. Future research avenues are also discussed, including high throughput phenotyping technology, the CRISPR/Cas9 Genome-Editing System, and genomic selection technology for molecular breeding of salt tolerance.展开更多
Gossypium anomalum represents an inestimable source of genes that could potentially be transferred into the gene pool of cultivated cotton. To resolve interspecific hybrid sterility problems, we previously treated tri...Gossypium anomalum represents an inestimable source of genes that could potentially be transferred into the gene pool of cultivated cotton. To resolve interspecific hybrid sterility problems, we previously treated triploid hybrids derived from a cross between Gossypium hirsutum and G. anomalum with 0.15% colchicine and obtained a putative fertile hexaploid. In this study, we performed morphological, molecular and cytological analyses to assess the hybridity and doubled status of putative interspecific hybrid plants. Most of the morphological characteristics of the putative hexaploid plants were intermediate between G. hirsutum and G.anomalum. Analysis of mitotic metaphase plates revealed 78 chromosomes, confirming the doubled hybrid status of the hexaploid. Genome-wide molecular analysis with different genome-derived SSR markers revealed a high level of polymorphism(96.6%) between G. hirsutum and G. anomalum. The marker transferability rate from other species to G. anomalum was as high as 98.0%. The high percentage of polymorphic markers with additive banding profiles in the hexaploid indicates the hybridity of the hexaploid on a genome-wide level. A-genome-derived markers were more powerful for distinguishing the genomic differences between G. hirsutum and G. anomalum than D-genome-derived markers. This study demonstrates the hybridity and chromosomally doubled status of the(G. anomalum × G. hirsutum)2hexaploid using morphological, cytological and molecular marker methods. The informative SSR markers screened in the study will be useful marker resources for tracking the flow of G. anomalum genetic material among progenies that may be produced by future backcrosses to G. hirsutum.展开更多
With the increasing promotion of simplified rapeseed cultivation in recent years,the development of cultivars with high resistance to herbicides is urgently needed.We previously developed M342,which shows sulfonylurea...With the increasing promotion of simplified rapeseed cultivation in recent years,the development of cultivars with high resistance to herbicides is urgently needed.We previously developed M342,which shows sulfonylurea herbicide resistance,by targeting acetohydroxyacid synthase(AHAS),a key enzyme in branched-chain amino acid synthesis.In the present study,we used a progeny line derived from M342 for an additional round of ethyl methane sulfonate mutagenesis,yielding the novel mutant DS3,which harbored two mutations in AHAS genes and showed high sulfonylurea resistance.One mutation was the substitution Trp574 Leu,as in M342,according to Arabidopsis protein sequencing.The other site was a newly recognized substitution,Pro197 Leu.A KASP marker targeting Pro197 Leu was developed and reliably predicted the response to sulfonylurea herbicides in the F2 population.The combination of Trp574 Leu and Pro197 Leu in DS3 produced a synergistic effect that greatly increased herbicide resistance.Analysis of the protein structures of AHAS1 and AHAS3 in wild-type and single-gene mutant plants revealed three-dimensional protein conformational changes that could account for differences in herbicide resistance characteristics including toxicity tolerance,AHAS enzyme activity,and AHAS gene expression.展开更多
[Objective] This study was to evaluate the high yielding and stability of candidate cultivars, depict the adaptive planting region, analyze trial location discrimination ability and representativeness, as well as iden...[Objective] This study was to evaluate the high yielding and stability of candidate cultivars, depict the adaptive planting region, analyze trial location discrimination ability and representativeness, as well as identify the ideal cultivar and trial location, with the aim to provide theory background for cultivar selection and reasonable scheme of test location in Jiangsu Province. [Method] The GGE biplot method was used to analyze the lint cotton yield of 12 experimental genotypes in the 6 test locations(three replicates in each) of the cotton regional trial in Jiangsu Province in 2013. [Result] The effects of genotype(G), environment(E), and genotype by environment interaction(G×E) on lint cotton yield were all highly significant(P<0.01), which made it necessary to further explore the specific pattern of genotype by environment interaction. Jinmian118(G4) and SF3303(G5) were the best ideal genotypes screened by the "ideal cultivar" and "ideal location" view of GGE biplot, and the ordination of test sites based on the ideal index were in the order of Dafeng(DF), Yanliang(YL), Liuhe(LH), Dongtai(DT), Yancheng(YC), and Nantong(NT), among which NT was relatively weak in representing of the whole target cotton planting region in Jiangsu Province. The "similarity among locations" view of GGE biplot clustered all trial locations into one group, showing that the test sites in the cotton planting region in Jiangsu Province were in the same mega-environment.The "which-won-where" view of GGE biplot indicated that cotton cultivar Jinmian118(G4) was the most appropriate cultivar in the homogeneous cotton planting region in Jiangsu Province. [Conclusion] Among the candidate cultivars, Jinmian118 and SF3303 were identified as the most ideal cultivars in this set of conventional cotton regional trial in Jiangsu Province; the test site of Dafeng ranked the first out of all locations in terms of discrimination and representativeness, and all test locations were clustered into the same mega-environmet, which indicated the high efficiency of cultivar selection in the cotton regional trial in Jiangsu Province.展开更多
Flax is a kind of worldwide fiber and oil crops, and it has a very important role in economic crop production in the world. With the development of molecular biology techniques, the research of flax molecular level ha...Flax is a kind of worldwide fiber and oil crops, and it has a very important role in economic crop production in the world. With the development of molecular biology techniques, the research of flax molecular level has a very big breakthrough. But, flax molecular biology researches are less reported due to the later starting. This paper summarized the latest research progress of molecular biology of flax, including molecular marker technology, construction of genetic map, gene engineering and omics researches, in order to provide the reference to understand the development and research status for flax molecular breeding researchers.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, a ...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
[Objective] The aim of this study was to explore the dominant fiber quality traits of test sites in cotton regional trials, by analyzing the regional characteristics of cotton fiber quality in Jiangsu province, in ord...[Objective] The aim of this study was to explore the dominant fiber quality traits of test sites in cotton regional trials, by analyzing the regional characteristics of cotton fiber quality in Jiangsu province, in order to provide the theory background for cotton fiber quality improvement. [Method] The dominant fiber quality traits of test locations were analyzed with eight main fiber quality indexes of hybrid cotton regional trials during 2009-2013 in Jiangsu province by use of the "ideal test site" view of GGE biplot. [Result] The test locations with the best integrative fiber quality were proved to be Yanliang, and followed by Dongxin and Guanyun; The better test locations in terms of the major fiber quality indexes, including fiber strength, fiber Length and micronaire value, were Guanyun, Xinyang and Yanliang; To sum up, the best test location with balanced fiber quality was Yanliang. The test locations with specialties in fiber quality index were listed as bellow: Dafeng, Xinghua and Dongtai performance better in fiber length; Qidong, Liuhe and Yanhai locations were of better fiber length uniformity; Sheyang and Dongxin were better in micronaire value;while Sheyang along was better in fiber elongation and reflectance. Moreover, the correlation between fiber yellowness and other traits was significant(P<0.01). [Conclusion] The regional characteristic of cotton fiber quality index in Jiangsu province was obvious and fiber yellowness was worthy an indicator trait to assist the comprehensive improvement of cotton fiber quality.展开更多
[Objective] Based on the cotton variety high yielding potential, fiber quality traits, disease resistance, and early maturity characters, a cultivar registration index model was developed to simplify the tedious calcu...[Objective] Based on the cotton variety high yielding potential, fiber quality traits, disease resistance, and early maturity characters, a cultivar registration index model was developed to simplify the tedious calculation process in national cotton registration procedure, and thus to enhance the practical application of cultivar registration index in cotton breeding and cotton recommending. [Method] By means of correlation analysis, partial correlation analysis and path analysis methods, the correlation of cotton main properties and their effects on cultivar registration index were explored using the dataset of national cotton regional trials in Yangtze River Valley during 1996-2013. The cultivar registration index model was constructed with stepwise regression statistical technique to ascertain the quantitative relationship of main characters with cultivar registration index, and the regional cotton trial dataset in 2013 was used to validate the model. [Result] Several characters with larger determinants to cultivar registration index were screened out, i.e. lint yield increase ratio,pro-frost yield ratio, verticillium wilt index, fiber strength, fusarium wilt index and micronaire value. The cultivar registration index model defined the functional relationship of cultivar registration index with the selected main characters, among which lint yield increase ratio, fiber strength and micronaire value contributed most to cultivar registration index. The model validation with regional cotton trials in 2013 indicated the root mean square error, RMSE was only 2.77, and the variation coefficient was 6.77%, which confirmed the model prediction effect was quite perfect.[Conclusion] The developed cultivar registration index model was reliable enough to simulate the complicated scoring system in cultivar registration procedure, also simplified cotton registration process, and enhanced the practicability of the cultivar registration index.展开更多
[Objective] This study was to analyze the high yielding, stability, adaptability and main characteristics of check cultivars in national cotton regional trials in the Yangtze River Valley in 2000-2013, with the aim to...[Objective] This study was to analyze the high yielding, stability, adaptability and main characteristics of check cultivars in national cotton regional trials in the Yangtze River Valley in 2000-2013, with the aim to provide theoretical basis for the reasonable selection of check cultivars for cotton regional trials. [Method] GGE biplot analysis method was used to carry out the intensive analysis and comprehensive comparisons on the performances and differences of the 9 major characters of check cultivars, namely, lint cotton yield, stability, and other main traits including boll weight, boll number, lint percentage, fiber length, fiber strength, micronaire value, plant height and seed index. [Result] Ezamian 10 was suitable in the majority of cotton planting regions in the Yangtze River Valley, with the best high yielding ability and perfect yield stability. The yielding ability of Xiangzamian 8 ranked the second, but its stability was the poorest. Xiangzamian 8 was of the specific adaptive cultivar with relatively good performance in high yielding but the poorest stability.The suitable planting areas of Xiangzamian 8 were limited to the cotton planting region around Dongting Lake in Hunan province, Poyang Lake in Jiangxi Province,the Coastal region in Jiangsu Province and Wuhan district in Hubei Province. Xiangzamian 2 performanced poorer in both yielding and stability, while Simian 3ranked first in stability but the last in yielding ability. The dominant character of Xiangzamian 8 and Xiangzamian 2 were high cotton plants and big bolls. Simian 3performanced super in lint percentage and fiber length. Ezamian 10 was strong in cotton boll formation ability, lint cotton yielding, fiber strength and seed size, as well as high micronaire value. [Conclusion] The outstanding performance of Ezamian 10 in high and stable yield in the Yangtze River Valley in recent years has effectively promoted the high yielding ability of candidate varieties in cotton regional trials in the area.展开更多
Background:Many studies have indicated that straw-returning could meet part or even all of the potassium(K)demand for crop growth in the field,but few have compared the effects of crop straw as K source and inorganic ...Background:Many studies have indicated that straw-returning could meet part or even all of the potassium(K)demand for crop growth in the field,but few have compared the effects of crop straw as K source and inorganic K fertilizer on carbon–nitrogen(C–N)balance of cotton and the reproductive growth.To address this,field experiments were conducted using the cotton cultivar,Siza 3,under there treatments(CK as control group one,no crop straw and inorganic K fertilizer were applied;K150 as control group two,150 kg·ha^(-1) of K2O was applied;and W9000,9000 kg·ha^(-1) wheat straw,which could provide K2O about 150 kg·ha^(-1),was incorporated into soil).Results:Although the final reproductive organ biomass did not differ between W9000 and K150,W9000 had a higher ratio of reproductive organ biomass to total biomass(RRT),suggesting that straw-returning was more conducive to the allocation of biomass to reproductive organs.The theoretical maximum biomass of reproductive organ was higher,but the average and maximum accumulation rates of reproductive organ biomass were 2.8%∼8.3%and 2.5%∼8.2%lower under W9000 than K150.Also,the duration of rapid-accumulation period for reproductive organ biomass(T)was 2.0∼2.8 d longer under W9000 than K150,which was a reason for the higher RRT under W9000.Straw-returning altered the dynamics of leaf K with the growth period,so that W9000 had a more drastic effect on leaf C metabolism than K150.Consequently,lower soluble sugar/free amino acid and C/N ratios were measured under W9000 than K150 at boll-setting(BSS)and boll-opening(BOS)stages.Higher leaf net photosynthetic rate,sucrose phosphate synthase and sucrose synthase activities,and lower acid invertase activity were observed under W9000 than K150 at BSS and BOS and these were more conducive to sucrose accumulation.However,less sucrose was measured under W9000 than K150 at these stages.This should be because straw-returning promoted the assimilate transport capacity when compared with inorganic K fertilizer application,which also explained the higher RRT under W9000 than K150.The lower acid invertase activity under W9000 inhibited the conversion of sucrose to other sugars,hence lower contents of soluble sugar and starch were measured under W9000 than K150.Conclusion:Under low K condition,crop straw as K source can increase the assimilate transport from source to sink,leading to lower C/N ratio in leaf and higher allocation of biomass to reproductive organs than inorganic K fertilizer.展开更多
With Sphaerotheca fuliginea as test object, the indoor antifungal activities of ethanol extracts from 30 kinds of Chinese herbs were measured by leaf disc method. The results showed that the extracts from Stellera cha...With Sphaerotheca fuliginea as test object, the indoor antifungal activities of ethanol extracts from 30 kinds of Chinese herbs were measured by leaf disc method. The results showed that the extracts from Stellera chamaejasma, Datura stramonium, Pericarpium zanthoxyli and Tetradium ruticarpum had the best control effect; when the concentration of extract was 10 g/L, the control effect of these four plants was greater than 90%; when the concentration was 5 g/L, the control effect of S. chamaejasma was 90.3%, and the control effects of D. stramonium, P. zanthoxyli and T. ruticarpum were also greater than 85%.展开更多
[Objective] The historical evolution pattern of nitrogen(N), phosphorus(P)and potassium(K) fertilizer application rate and its effects on lint cotton yield were explored to provide the theoretical basis for reasonable...[Objective] The historical evolution pattern of nitrogen(N), phosphorus(P)and potassium(K) fertilizer application rate and its effects on lint cotton yield were explored to provide the theoretical basis for reasonable fertilizer management strategy in the cotton planting region of the Yangtze River Valley. [Method] GGE biplot analysis method was adopted to analyze the correlation among N, P and K fertilizer application rate and lint cotton yield with the dataset of national cotton regional trials of the Yangtze River Valley during 1991-2013. The linear and nonlinear regression analysis method was used to reveal the evolution of the fertilizer applying patterns,and analyze the effects of N, P, K application rates on cotton lint yield. [Result] The application rates of N, P and K fertilizer presented highly significant positive correlation with lint cotton yield, among which the potassium fertilizer was the strongest relative factor with lint cotton yield, followed by phosphorus fertilizer, while nitrogen fertilizer was the weakest factor. The application rate of nitrogen fertilizer was related with the test year in the pattern of a quadratic function, while phosphate and potassium had progressive increase linear relation with the test year in the cotton planting region of the Yangtze River Valley. Meanwhile, cotton lint yield was in response to nitrogen fertilizer content increase with a quadratic parabola function, and increased with the applying phosphate fertilizer and potassium fertilizer content with linearly increasing function. [Conclusion] The increasing application amount of N, P and K fertilizer was generally beneficial to cotton yield improvements, however, exorbitant applying nitrogen fertilizer was unfavorable for cotton production, and a reasonable mixture formula of N, P and K fertilizer was better in terms of cotton yield-increasing effect.展开更多
The fatty acid desaturase 2(fad2) gene was proven to be a major locus for high oleic acid(C18:1).Brassica napus is an amphidiploid species originating from a spontaneous hybridization of Brassica rapa and Brassica ole...The fatty acid desaturase 2(fad2) gene was proven to be a major locus for high oleic acid(C18:1).Brassica napus is an amphidiploid species originating from a spontaneous hybridization of Brassica rapa and Brassica oleracea.B.napus contains multiple copies in genome for most of the genes,including fad2 genes.The research cloned nine fad2 genes from 3 varieties of B.rapa and 3 varieties of B.oleracea,respectively.Alignment of the nine fad2 sequences from B.rapa and B.oleracea detected 6 single nucleotide polymorphic sites,which resulted in 6 amino-acid substitutions.The nucleotide substitutions at position 743 bp in the fad2-A gene and position 947 bp in the fad2-C gene were used as 3' end of allele-specific primers.In use of the allele-specific primers to amplify fad2 gene,we could identify if the fad2 gene originated from A genome or C genome.Besides,the research found that fad2 genes in C genome are more conserved in evolutionary process than those in A genome.The fad2 expression data reported in this study revealed that fad2-A from B.rapa was not only expressed in siliques same as fad2-C from B.oleracea,but also expressed in a high level in stems.Not even the less,fad2 gene from B.napus was expressed higher in roots and flowers.All these results provided evidences that fad2,though it was expressed differently in B.rapa and B.oleracea,but it was regulated by the same approach in B.napus.展开更多
基金supported by the State Key Laboratory of Cotton Biology Open Fund,China(CB2021A18)the Youth Scientific Research Foundation of Shandong Academy of Agricultural Sciences,China(2016YQN09)+1 种基金the Improved Variety Project of Shandong Province,China(2020LZGC002)the China Agriculture Research System of MOF and MARA(CARS-15-05).
文摘One of the most important objectives for breeders is to develop high-yield cultivars.The increase in crop yield has met with bottlenecks after the first green revolution,and more recent efforts have been focusing on achieving high photosynthetic efficiency traits in order to enhance the yield.Leaf shape is a significant agronomic trait of upland cotton that affects plant and canopy architecture,yield,and other production attributes.The major leaf shape types,including normal,sub-okra,okra,and super-okra,with varying levels of lobe severity,are controlled by a multiple allelic series of the D-genome locus L-D_(1).To analyze the effects of L-D_(1)alleles on leaf morphology,photosynthetic related traits and yield of cotton,two sets of near isogenic lines(NILs)with different alleles were constructed in Lumianyan 22(LMY22)and Lumianyan 28(LMY28)backgrounds.The analysis of morphological parameters and the results of virus-induced gene silencing(VIGS)showed that the regulation of leaf shape by L-D_(1)alleles was similar to a gene-dosage effect.Compared with the normal leaf,deeper lobes of the sub-okra leaf improved plant canopy structure by decreasing the leaf area index(LAI)and increasing the light transmittance rate(LTR),and the mid-range LAI of sub-okra leaf also guaranteed the accumulation of cotton biomass.Although the chlorophyll content(SPAD)of sub-okra leaf was lower than those of the other two leaf shapes,the net photosynthetic rate(Pn)of sub-okra leaf was higher than those of okra leaf and normal leaf at most stages.Thus,the improvements in canopy structure,as well as photosynthetic and physiological characteristics,contributed to optimizing the light environment,thereby increasing the total biomass and yield in the lines with a sub-okra leaf shape.Our results suggest that the sub-okra leaf may have practical application in cultivating varieties,and could enhance sustainable and profitable cotton production.
基金supported by the National Natural Science Foundation of China(32071968)the Jiangsu Agricultural Science and Technology Innovation Fund,China(CX(22)2015))the Jiangsu Collaborative Innovation Center for Modern Crop Production,China。
文摘Straw return is a promising strategy for managing soil organic carbon(SOC)and improving yield stability.However,the optimal straw return strategy for sustainable crop production in the wheat(Triticum aestivum L.)-cotton(Gossypium hirsutum L.)cropping system remains uncertain.The objective of this study was to quantify the long-term(10 years)impact of carbon(C)input on SOC sequestration,soil aggregation and crop yields in a wheat-cotton cropping system in the Yangtze River Valley,China.Five treatments were arranged with a single-factor randomized design as follows:no straw return(Control),return of wheat straw only(Wt),return of cotton straw only(Ct),return of 50%wheat and 50%cotton straw(Wh-Ch)and return of 100%wheat and 100%cotton straw(Wt-Ct).In comparison to the Control,the SOC content increased by 8.4 to 20.2%under straw return.A significant linear positive correlation between SOC sequestration and C input(1.42-7.19 Mg ha^(−1)yr^(−1))(P<0.05)was detected.The percentages of aggregates of sizes>2 and 1-2 mm at the 0-20 cm soil depth were also significantly elevated under straw return,with the greatest increase of the aggregate stability in the Wt-Ct treatment(28.1%).The average wheat yields increased by 12.4-36.0%and cotton yields increased by 29.4-73.7%,and significantly linear positive correlations were also detected between C input and the yields of wheat and cotton.The average sustainable yield index(SYI)reached a maximum value of 0.69 when the C input was 7.08 Mg ha^(−1)yr^(−1),which was close to the maximum value(SYI of 0.69,C input of 7.19 Mg ha^(−1)yr^(-1))in the Wt-Ct treatment.Overall,the return of both wheat and cotton straw was the best strategy for improving SOC sequestration,soil aggregation,yields and their sustainability in the wheat-cotton rotation system.
基金supported by the National Natural Science Foundation of China(31671731)the National Key Research and Development Program of China(2016YFD0101300)+2 种基金the China Agricultural Research System(CARS-13)the Natural Science Foundation of Jiangsu Province,China(BK20151369)the Science Foundation of Jiangsu Academy of Agricultural Sciences,China(6111618)
文摘Rapeseed is a very important oil crop in China;however,its production is challenging due to the absence of effective weed management strategies.This is predominantly because of a shortage of herbicide resistance genes.Acetohydroxyacid synthase(AHAS) herbicides inhibit AHAS,a key enzyme involved in branched-chain amino acid synthesis that is required for plant growth.A rapeseed line designated M342 with AHAS herbicide resistance was developed through seed mutagenesis and was studied to assess the level and mode of inheritance of the resistance and to identify the molecular basis of resistance.M342 possessed a high level of cross-resistance to sulfonylureas(SUs) and imidazolinones(IMIs).This resistance was due to AHAS insensitivity to these herbicides and was inherited as a dominant trait conferred by a single nuclear-encoded gene.Molecular analysis revealed the presence of a Trp574 Leu mutation in M342,and an allele-specific cleaved amplified polymorphic sequence(AS-CAPS) marker was developed and cosegregated with herbicide resistance in the F2,BC1,and BC2 populations.This mutation altered the transcript levels of Bn AHAS1 and Bn AHAS3 in M342 compared with those in the wild type,but it did not affect the agronomic or quality traits.The simple genetic inheritance of this mutation and the availability of the cleaved amplified polymorphic sequence(CAPS) marker and herbicide resistance gene should facilitate the development of herbicide-resistant rapeseed cultivars for effective weed control in China.
基金funded by the Jiangsu Agriculture Science and Technology Innovation Fund,China(CX(12)5035)the National Natural Science Foundation of China(30971735)+1 种基金the China Agriculture Research System(CARS-18-20)the Special Fund for Agro-Scientific Research in the Public Interest of China(Impact of Climate Change on Agriculture Production of China,200903003)
文摘In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to governmental organizations in charge of cultivar registration. Where competition among breeding companies exists, effective and fair multi-environment variety trials are of utmost importance to motivate investment in breeding. The objective of this study was to use genotype main effect plus genotype by environment interaction(GGE) biplot analysis to evaluate test locations in terms of discrimination ability, representativeness and desirability, and to investigate the presence of multiple mega-environments in cotton production in the Yangtze River Valley(YaRV), China. Four traits(cotton lint yield, fiber length, lint breaking tenacity, micronaire) and two composite selection indices were considered. It was found that the assumption of a single mega-environment in the YaRV for cotton production does not hold. The YaRV consists of three cotton mega-environments: a main one represented by 11 locations and two minor ones represented by two test locations each. This demands that the strategy of cotton variety registration or recommendation must be adjusted. GGE biplot analysis has also led to the identification of test location superior for cotton variety evaluation. Although test location desirable for selecting different traits varied greatly, Jinzhou, Hubei Province, China, was found to be desirable for selecting for all traits considered while Jianyang, Sichuan Province, China, was found to be desirable for none.
基金supported by the Science Foundation Project of Chongqing Normal University and Gansu Province,China(QS041-C31-09).
文摘Influences of PGR, sucrose, and ammonium nitrate on in vitro flowering and fruiting from cotyledon explants of P.frutescens were studied. The regenerated shoots at 2-4 cm from cotyledon explants on MS medium supplemented with0.5 mg L-1 BA and 1.0 mg L-1 IAA were excised and transferred to MS medium containing 30 g L-1 sucrose, 8.25 g L-1ammonium nitrate, and 1.0 mg L-1 BA. Following 40 d of culture, 86.2% of them flowered and set seeds. These seeds weregerminable and developed into flowering plants in the fields. This study provides a simple system for rapid breeding ofP. frutescens and studying the physiological mechanism of flowering of plants.
基金financially supported by the National Natural Science Foundation of China(31701882)the Competitive Nature Project of the Hubei Academy of Agricultural Sciences,China(2016JZXJH006)the Agricultural Science and Technology Innovation Center Program of Hubei Province,China(2016-620-000-001-014)
文摘The ascomycete fungus Colletotrichum gloeosporioides is a devastating plant pathogen with a wide host range and worldwide distribution. Carbendazim has been widely used to control anthracnose caused by the C. gloeosporioides complex in China for more than 30 years and resistance to carbendazim has been reported in China. A total of 125 Colletotrichum isolates of strawberry and yam were collected from different geographical regions in Hubei Province, China. Approximately 52.8% of Colletotrichum spp. isolates showed resistance to carbendazim. The isolates tested in this study belong to four species, and the frequencies of resistant isolates differed across Colletotrichum species. Resistant isolates were found in C. siamense and C. fructicola. In contrast, all isolates of C. gloeosporioides and C. aenigma were sensitive to carbendazim. Highly carbendazim-resistant isolates harbored the E198 A mutation in the β-tubulin 2(TUB2) gene, whereas moderately carbendazim-resistant isolates harbored the F200 Y mutation in the TUB2 gene. Carbendazim-sensitive Colletotrichum isolates in this study were not genetically similar enough to form a separate cluster from resistant isolates. The result of this study emphasizes the importance of knowing which Colletotrichum sp. is present, when strategies for disease control are made.
基金supported by the National Natural Science Foundation of China (31401407)
文摘Salt stress is one of the major abiotic stresses affecting soybean growth. Genetic improvement for salt tolerance is an effective way to protect soybean yield under salt stress conditions. Successful improvement of salt tolerance in soybean relies on identifying genetic variation that confers tolerance in soybean germplasm and subsequently incorporating these genetic resources into cultivars. In this review, we summarize the progress in genetic diversity and genetics of salt tolerance in soybean, which includes identifying genetic diversity for salt tolerant germplasm; mapping QTLs conferring salt tolerance; map-based cloning; and conducting genome-wide association study(GWAS) analysis in soybean. Future research avenues are also discussed, including high throughput phenotyping technology, the CRISPR/Cas9 Genome-Editing System, and genomic selection technology for molecular breeding of salt tolerance.
基金supported by the National Natural Science Foundation of China(31171595)the Independent Innovation Funds for Agricultural Technology of Jiangsu Province,China[CX(12)5039]
文摘Gossypium anomalum represents an inestimable source of genes that could potentially be transferred into the gene pool of cultivated cotton. To resolve interspecific hybrid sterility problems, we previously treated triploid hybrids derived from a cross between Gossypium hirsutum and G. anomalum with 0.15% colchicine and obtained a putative fertile hexaploid. In this study, we performed morphological, molecular and cytological analyses to assess the hybridity and doubled status of putative interspecific hybrid plants. Most of the morphological characteristics of the putative hexaploid plants were intermediate between G. hirsutum and G.anomalum. Analysis of mitotic metaphase plates revealed 78 chromosomes, confirming the doubled hybrid status of the hexaploid. Genome-wide molecular analysis with different genome-derived SSR markers revealed a high level of polymorphism(96.6%) between G. hirsutum and G. anomalum. The marker transferability rate from other species to G. anomalum was as high as 98.0%. The high percentage of polymorphic markers with additive banding profiles in the hexaploid indicates the hybridity of the hexaploid on a genome-wide level. A-genome-derived markers were more powerful for distinguishing the genomic differences between G. hirsutum and G. anomalum than D-genome-derived markers. This study demonstrates the hybridity and chromosomally doubled status of the(G. anomalum × G. hirsutum)2hexaploid using morphological, cytological and molecular marker methods. The informative SSR markers screened in the study will be useful marker resources for tracking the flow of G. anomalum genetic material among progenies that may be produced by future backcrosses to G. hirsutum.
基金supported by the National Natural Science Foundation of China(31870519,31901503 and 31671731)the National Key Research and Development Program of China(2016YFD0101300 and 2016YFD0100202-10)+1 种基金the China Agriculture Research System(CARS-12)the Natural Science Foundation of Jiangsu Province(BK20190267)。
文摘With the increasing promotion of simplified rapeseed cultivation in recent years,the development of cultivars with high resistance to herbicides is urgently needed.We previously developed M342,which shows sulfonylurea herbicide resistance,by targeting acetohydroxyacid synthase(AHAS),a key enzyme in branched-chain amino acid synthesis.In the present study,we used a progeny line derived from M342 for an additional round of ethyl methane sulfonate mutagenesis,yielding the novel mutant DS3,which harbored two mutations in AHAS genes and showed high sulfonylurea resistance.One mutation was the substitution Trp574 Leu,as in M342,according to Arabidopsis protein sequencing.The other site was a newly recognized substitution,Pro197 Leu.A KASP marker targeting Pro197 Leu was developed and reliably predicted the response to sulfonylurea herbicides in the F2 population.The combination of Trp574 Leu and Pro197 Leu in DS3 produced a synergistic effect that greatly increased herbicide resistance.Analysis of the protein structures of AHAS1 and AHAS3 in wild-type and single-gene mutant plants revealed three-dimensional protein conformational changes that could account for differences in herbicide resistance characteristics including toxicity tolerance,AHAS enzyme activity,and AHAS gene expression.
基金Supported by the Fund for Independent Innovation of Agricultural Sciences in Jiangsu Province(CX-12-5035)
文摘[Objective] This study was to evaluate the high yielding and stability of candidate cultivars, depict the adaptive planting region, analyze trial location discrimination ability and representativeness, as well as identify the ideal cultivar and trial location, with the aim to provide theory background for cultivar selection and reasonable scheme of test location in Jiangsu Province. [Method] The GGE biplot method was used to analyze the lint cotton yield of 12 experimental genotypes in the 6 test locations(three replicates in each) of the cotton regional trial in Jiangsu Province in 2013. [Result] The effects of genotype(G), environment(E), and genotype by environment interaction(G×E) on lint cotton yield were all highly significant(P<0.01), which made it necessary to further explore the specific pattern of genotype by environment interaction. Jinmian118(G4) and SF3303(G5) were the best ideal genotypes screened by the "ideal cultivar" and "ideal location" view of GGE biplot, and the ordination of test sites based on the ideal index were in the order of Dafeng(DF), Yanliang(YL), Liuhe(LH), Dongtai(DT), Yancheng(YC), and Nantong(NT), among which NT was relatively weak in representing of the whole target cotton planting region in Jiangsu Province. The "similarity among locations" view of GGE biplot clustered all trial locations into one group, showing that the test sites in the cotton planting region in Jiangsu Province were in the same mega-environment.The "which-won-where" view of GGE biplot indicated that cotton cultivar Jinmian118(G4) was the most appropriate cultivar in the homogeneous cotton planting region in Jiangsu Province. [Conclusion] Among the candidate cultivars, Jinmian118 and SF3303 were identified as the most ideal cultivars in this set of conventional cotton regional trial in Jiangsu Province; the test site of Dafeng ranked the first out of all locations in terms of discrimination and representativeness, and all test locations were clustered into the same mega-environmet, which indicated the high efficiency of cultivar selection in the cotton regional trial in Jiangsu Province.
基金Supported by the National Natural Science Foundation of China(31401451)National Agro-industry Technology Research System for Crops of Bast and Leaf Fiber(CARS-19-S03)
文摘Flax is a kind of worldwide fiber and oil crops, and it has a very important role in economic crop production in the world. With the development of molecular biology techniques, the research of flax molecular level has a very big breakthrough. But, flax molecular biology researches are less reported due to the later starting. This paper summarized the latest research progress of molecular biology of flax, including molecular marker technology, construction of genetic map, gene engineering and omics researches, in order to provide the reference to understand the development and research status for flax molecular breeding researchers.
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Supported by Special Program to Cultivate New Species of National Genetically Modified Food(2012ZX08013016)
文摘[Objective] The aim of this study was to explore the dominant fiber quality traits of test sites in cotton regional trials, by analyzing the regional characteristics of cotton fiber quality in Jiangsu province, in order to provide the theory background for cotton fiber quality improvement. [Method] The dominant fiber quality traits of test locations were analyzed with eight main fiber quality indexes of hybrid cotton regional trials during 2009-2013 in Jiangsu province by use of the "ideal test site" view of GGE biplot. [Result] The test locations with the best integrative fiber quality were proved to be Yanliang, and followed by Dongxin and Guanyun; The better test locations in terms of the major fiber quality indexes, including fiber strength, fiber Length and micronaire value, were Guanyun, Xinyang and Yanliang; To sum up, the best test location with balanced fiber quality was Yanliang. The test locations with specialties in fiber quality index were listed as bellow: Dafeng, Xinghua and Dongtai performance better in fiber length; Qidong, Liuhe and Yanhai locations were of better fiber length uniformity; Sheyang and Dongxin were better in micronaire value;while Sheyang along was better in fiber elongation and reflectance. Moreover, the correlation between fiber yellowness and other traits was significant(P<0.01). [Conclusion] The regional characteristic of cotton fiber quality index in Jiangsu province was obvious and fiber yellowness was worthy an indicator trait to assist the comprehensive improvement of cotton fiber quality.
基金Supported by National Major Projects for the GMO Cultivation of New Varieties in China(2012ZX08013015)
文摘[Objective] Based on the cotton variety high yielding potential, fiber quality traits, disease resistance, and early maturity characters, a cultivar registration index model was developed to simplify the tedious calculation process in national cotton registration procedure, and thus to enhance the practical application of cultivar registration index in cotton breeding and cotton recommending. [Method] By means of correlation analysis, partial correlation analysis and path analysis methods, the correlation of cotton main properties and their effects on cultivar registration index were explored using the dataset of national cotton regional trials in Yangtze River Valley during 1996-2013. The cultivar registration index model was constructed with stepwise regression statistical technique to ascertain the quantitative relationship of main characters with cultivar registration index, and the regional cotton trial dataset in 2013 was used to validate the model. [Result] Several characters with larger determinants to cultivar registration index were screened out, i.e. lint yield increase ratio,pro-frost yield ratio, verticillium wilt index, fiber strength, fusarium wilt index and micronaire value. The cultivar registration index model defined the functional relationship of cultivar registration index with the selected main characters, among which lint yield increase ratio, fiber strength and micronaire value contributed most to cultivar registration index. The model validation with regional cotton trials in 2013 indicated the root mean square error, RMSE was only 2.77, and the variation coefficient was 6.77%, which confirmed the model prediction effect was quite perfect.[Conclusion] The developed cultivar registration index model was reliable enough to simulate the complicated scoring system in cultivar registration procedure, also simplified cotton registration process, and enhanced the practicability of the cultivar registration index.
基金Supported by National Key Special Project for Breeding and Cultivation of GMO Varieties in China(2012ZX08013016)the Special Project of Regional Crop Trials from the Ministry of Agriculture of China(2911108)
文摘[Objective] This study was to analyze the high yielding, stability, adaptability and main characteristics of check cultivars in national cotton regional trials in the Yangtze River Valley in 2000-2013, with the aim to provide theoretical basis for the reasonable selection of check cultivars for cotton regional trials. [Method] GGE biplot analysis method was used to carry out the intensive analysis and comprehensive comparisons on the performances and differences of the 9 major characters of check cultivars, namely, lint cotton yield, stability, and other main traits including boll weight, boll number, lint percentage, fiber length, fiber strength, micronaire value, plant height and seed index. [Result] Ezamian 10 was suitable in the majority of cotton planting regions in the Yangtze River Valley, with the best high yielding ability and perfect yield stability. The yielding ability of Xiangzamian 8 ranked the second, but its stability was the poorest. Xiangzamian 8 was of the specific adaptive cultivar with relatively good performance in high yielding but the poorest stability.The suitable planting areas of Xiangzamian 8 were limited to the cotton planting region around Dongting Lake in Hunan province, Poyang Lake in Jiangxi Province,the Coastal region in Jiangsu Province and Wuhan district in Hubei Province. Xiangzamian 2 performanced poorer in both yielding and stability, while Simian 3ranked first in stability but the last in yielding ability. The dominant character of Xiangzamian 8 and Xiangzamian 2 were high cotton plants and big bolls. Simian 3performanced super in lint percentage and fiber length. Ezamian 10 was strong in cotton boll formation ability, lint cotton yielding, fiber strength and seed size, as well as high micronaire value. [Conclusion] The outstanding performance of Ezamian 10 in high and stable yield in the Yangtze River Valley in recent years has effectively promoted the high yielding ability of candidate varieties in cotton regional trials in the area.
基金funded by the National Key R&D Program of China(2020YFD1001002)Fundamental Research Funds for the Central Universities(KYLH201901)Jiangsu Collaborative Innovation Center for Modern Crop Production(JCIC-MCP).
文摘Background:Many studies have indicated that straw-returning could meet part or even all of the potassium(K)demand for crop growth in the field,but few have compared the effects of crop straw as K source and inorganic K fertilizer on carbon–nitrogen(C–N)balance of cotton and the reproductive growth.To address this,field experiments were conducted using the cotton cultivar,Siza 3,under there treatments(CK as control group one,no crop straw and inorganic K fertilizer were applied;K150 as control group two,150 kg·ha^(-1) of K2O was applied;and W9000,9000 kg·ha^(-1) wheat straw,which could provide K2O about 150 kg·ha^(-1),was incorporated into soil).Results:Although the final reproductive organ biomass did not differ between W9000 and K150,W9000 had a higher ratio of reproductive organ biomass to total biomass(RRT),suggesting that straw-returning was more conducive to the allocation of biomass to reproductive organs.The theoretical maximum biomass of reproductive organ was higher,but the average and maximum accumulation rates of reproductive organ biomass were 2.8%∼8.3%and 2.5%∼8.2%lower under W9000 than K150.Also,the duration of rapid-accumulation period for reproductive organ biomass(T)was 2.0∼2.8 d longer under W9000 than K150,which was a reason for the higher RRT under W9000.Straw-returning altered the dynamics of leaf K with the growth period,so that W9000 had a more drastic effect on leaf C metabolism than K150.Consequently,lower soluble sugar/free amino acid and C/N ratios were measured under W9000 than K150 at boll-setting(BSS)and boll-opening(BOS)stages.Higher leaf net photosynthetic rate,sucrose phosphate synthase and sucrose synthase activities,and lower acid invertase activity were observed under W9000 than K150 at BSS and BOS and these were more conducive to sucrose accumulation.However,less sucrose was measured under W9000 than K150 at these stages.This should be because straw-returning promoted the assimilate transport capacity when compared with inorganic K fertilizer application,which also explained the higher RRT under W9000 than K150.The lower acid invertase activity under W9000 inhibited the conversion of sucrose to other sugars,hence lower contents of soluble sugar and starch were measured under W9000 than K150.Conclusion:Under low K condition,crop straw as K source can increase the assimilate transport from source to sink,leading to lower C/N ratio in leaf and higher allocation of biomass to reproductive organs than inorganic K fertilizer.
文摘With Sphaerotheca fuliginea as test object, the indoor antifungal activities of ethanol extracts from 30 kinds of Chinese herbs were measured by leaf disc method. The results showed that the extracts from Stellera chamaejasma, Datura stramonium, Pericarpium zanthoxyli and Tetradium ruticarpum had the best control effect; when the concentration of extract was 10 g/L, the control effect of these four plants was greater than 90%; when the concentration was 5 g/L, the control effect of S. chamaejasma was 90.3%, and the control effects of D. stramonium, P. zanthoxyli and T. ruticarpum were also greater than 85%.
基金Supported by National Major Projects for the GMO Cultivation of New Varieties in China(2012ZX08013015)
文摘[Objective] The historical evolution pattern of nitrogen(N), phosphorus(P)and potassium(K) fertilizer application rate and its effects on lint cotton yield were explored to provide the theoretical basis for reasonable fertilizer management strategy in the cotton planting region of the Yangtze River Valley. [Method] GGE biplot analysis method was adopted to analyze the correlation among N, P and K fertilizer application rate and lint cotton yield with the dataset of national cotton regional trials of the Yangtze River Valley during 1991-2013. The linear and nonlinear regression analysis method was used to reveal the evolution of the fertilizer applying patterns,and analyze the effects of N, P, K application rates on cotton lint yield. [Result] The application rates of N, P and K fertilizer presented highly significant positive correlation with lint cotton yield, among which the potassium fertilizer was the strongest relative factor with lint cotton yield, followed by phosphorus fertilizer, while nitrogen fertilizer was the weakest factor. The application rate of nitrogen fertilizer was related with the test year in the pattern of a quadratic function, while phosphate and potassium had progressive increase linear relation with the test year in the cotton planting region of the Yangtze River Valley. Meanwhile, cotton lint yield was in response to nitrogen fertilizer content increase with a quadratic parabola function, and increased with the applying phosphate fertilizer and potassium fertilizer content with linearly increasing function. [Conclusion] The increasing application amount of N, P and K fertilizer was generally beneficial to cotton yield improvements, however, exorbitant applying nitrogen fertilizer was unfavorable for cotton production, and a reasonable mixture formula of N, P and K fertilizer was better in terms of cotton yield-increasing effect.
基金Supported by the National Natural Science Foundation of China (31301357)the Natural Science Foundation of Jiangsu Province,China (BK20130719)
文摘The fatty acid desaturase 2(fad2) gene was proven to be a major locus for high oleic acid(C18:1).Brassica napus is an amphidiploid species originating from a spontaneous hybridization of Brassica rapa and Brassica oleracea.B.napus contains multiple copies in genome for most of the genes,including fad2 genes.The research cloned nine fad2 genes from 3 varieties of B.rapa and 3 varieties of B.oleracea,respectively.Alignment of the nine fad2 sequences from B.rapa and B.oleracea detected 6 single nucleotide polymorphic sites,which resulted in 6 amino-acid substitutions.The nucleotide substitutions at position 743 bp in the fad2-A gene and position 947 bp in the fad2-C gene were used as 3' end of allele-specific primers.In use of the allele-specific primers to amplify fad2 gene,we could identify if the fad2 gene originated from A genome or C genome.Besides,the research found that fad2 genes in C genome are more conserved in evolutionary process than those in A genome.The fad2 expression data reported in this study revealed that fad2-A from B.rapa was not only expressed in siliques same as fad2-C from B.oleracea,but also expressed in a high level in stems.Not even the less,fad2 gene from B.napus was expressed higher in roots and flowers.All these results provided evidences that fad2,though it was expressed differently in B.rapa and B.oleracea,but it was regulated by the same approach in B.napus.
