Background Ensuring that seeds germinate and emerge normally is a prerequisite for cotton production,esp.in areas with salinized soil.Priming with mepiquat chloride(MC)can promote seed germination and root growth unde...Background Ensuring that seeds germinate and emerge normally is a prerequisite for cotton production,esp.in areas with salinized soil.Priming with mepiquat chloride(MC)can promote seed germination and root growth under salt stress,but its mechanism has not been fully elucidated.In this study,physiological and biochemical experiments revealed that MC-priming promotes the tolerance of cotton seeds to salt stress by increasing the ability of antioxidant enzymes related to the ascorbate-glutathione(AsA-GSH)cycle to scavenge reactive oxygen species(ROS).Results Results revealed that treatment with inhibitors of abscisic acid(ABA)and γ-aminobutyric acid(GABA)biosynthesis reduced the positive effects of MC-priming.Similarly,MC-priming increased the contents of ABA and GABA under salt stress by stimulating the expression levels of GhNCED2 and GhGAD4 and the activity of calmodulin-binding(CML)glutamate decarboxylase(GAD).Further analysis showed that an inhibitor of ABA synthesis reduced the positive impacts of MC-priming on the content of GABA under salt stress,but the content of ABA was not affected by the GABA synthesis inhibitor.Furthermore,a multi-omics analysis revealed that MC-priming increased the abundance and phosphorylation levels of the proteins related to ABA signaling,CML,and Ca^(2+)channels/transporters in the MC-primed treatments,which resulted in increased oscillations in Ca^(2+)in the MC-primed cotton seeds under salt stress.Conclusion In summary,these results demonstrate that MC-mediated ABA signaling operates upstream of the GABA synthesis generated by GAD by activating the oscillations of Ca^(2+)and then enhancing activity of the AsA-GSH cycle,which ensures that cotton seeds are tolerant to salt stress.展开更多
【目的】综合评价棉花品种(系)出苗期耐冷性,建立可靠评价模型,筛选鉴定指标,为耐冷品种选育鉴定提供简便有效的评价方法。【方法】以200份陆地棉品种(系)为试验材料,设恒定低温、昼夜变温和适宜温度3个处理,测定其出苗率、下胚轴长、...【目的】综合评价棉花品种(系)出苗期耐冷性,建立可靠评价模型,筛选鉴定指标,为耐冷品种选育鉴定提供简便有效的评价方法。【方法】以200份陆地棉品种(系)为试验材料,设恒定低温、昼夜变温和适宜温度3个处理,测定其出苗率、下胚轴长、根长、百粒重等指标,采用耐冷系数差异分析、频次分析、降幅分析、主成分分析、聚类分析和多元回归分析等方法,对群体进行耐冷型划分,并建立耐冷性评价模型和确定鉴定指标。【结果】各指标在适宜温度下变异幅度较小,变异系数为3.12%—18.89%,各品种(系)出苗率在85.00%以上,具有较高的生活力,可用于后续耐冷性分析。在低温胁迫下群体内各指标变异幅度增大,为7.14%—108.33%,在恒定低温和昼夜变温下,变幅最大的指标依次为根长和萌发指数。主成分分析将14个低温相关指标和百粒重转换为6个相互独立的综合指标,代表了全部数据74.98%的信息量。利用隶属函数法计算综合耐冷评价值(D),并对其进行聚类分析,按照耐冷性强弱将200份陆地棉品种(系)划分为5类,第Ⅰ类群属于强耐冷型共2份,第Ⅱ类群属于耐冷型共42份,第Ⅲ类群属于中耐冷型共69份,第Ⅳ类群属于较敏感型共83份,第Ⅴ类群属于敏感型共4份,其中,新陆中16号为耐冷性最强的品种。采用多元回归分析方法,建立棉花出苗期耐冷性预测模型为Y=-4.10+0.58 X 4+0.40 X 14+0.32 X 1+0.22 X 5(R 2=0.92),筛选出4个耐冷性鉴定指标,分别为恒定低温下的棉苗总长、出苗率、干物重和昼夜变温下的萌发率。田间早播试验中各品种(系)的出苗率,与室内试验结果基本一致。【结论】采用恒定低温和昼夜变温处理结合多元统计分析方法对棉花出苗期耐冷性评价是可行的,恒定低温下的棉苗总长、出苗率、干物重和昼夜变温下的萌发率,可作为鉴定指标。展开更多
Background: Large quantities of nitrogen (N) fertilizer applied to cotton cropping systems support high yields but cause adverse environmental impacts such as N20 emission and water eutrophication. The development ...Background: Large quantities of nitrogen (N) fertilizer applied to cotton cropping systems support high yields but cause adverse environmental impacts such as N20 emission and water eutrophication. The development of cotton cultivars with higher N use efficiencies suitable for low-N conditions is therefore important for sustainable production. In this study, we evaluated 100 cotton genotypes in 2016 for N use efficiency and related traits at the seedling stage. Methods: Sand culture experiment was conducted with low N levels (0.01 g.kg i) or normal N levels (0.1 g.kg i). We investigated plant height, SPAD value (soil plant analysis development chlorophyll meter), dry weight, N accumulation, N utilization efficiency, and N uptake efficiency. Through descriptive statistics, principal component analysis and heatmap clustering analysis, we confirmed the evaluation index system of N-efficient genotypes and the classification of N-efficient genotypes. Results: Significant differences were observed among N levels and genotypes for all agronomic traits and N levels. Coefficients of variation varied greatly and ranged from 6.7N28.8 and 7.4N20.8 under low-N and normal-N treatment, respectively. All traits showed highly significant positive correlations with each other, except SPAD value. The principal components under both N levels were similar, showing that total dry weight, aboveground dry weight, total N accumulation, and N uptake efficiency were important components. We confirmed these four traits as suitable screening indexes for low N tolerance. Based on the results of heatmap clustering and scatter diagram analysis of N efficiency value, 10 genotypes were found low-N tolerant, in which five varieties were inefficient under both low and normal N conditions, while four varieties were found efficient under low-N conditions but inefficient under normal-N conditions. Only one variety was efficient under both low and normal-N conditions. Meanwhile, 20 genotypes were identified as low-N sensitive ones, in which 19 genotypes were inefficient under low-N conditions but efficient under normal-N conditions, one variety was inefficient under both low and normal-N conditions. Conclusion: We preliminarily identified Kashi as a low-N tolerant and N-efficient cotton genotype, and CCRI 64 as a low- N sensitive and N-inefficient cotton genotype. Further studies should be carried out to verify the yield and heritability effect of specific genotypes in the field.展开更多
Background:Salt stress significantly inhibits the growth,development,and productivity of cotton because of osmotic,ionic,and oxidative stresses.Therefore,the screening and development of salt tolerant cotton cultivars...Background:Salt stress significantly inhibits the growth,development,and productivity of cotton because of osmotic,ionic,and oxidative stresses.Therefore,the screening and development of salt tolerant cotton cultivars is a key issue towards sustainable agriculture.This study subjected 11 upland cotton genotypes at the seedling growth stage to five different salt concentrations and evaluated their salt tolerance and reliable traits.Results:Several morpho-physiological traits were measured after 10 days of salinity treatment and the salt tolerance performance varied significantly among the tested cotton genotypes.The optimal Na Cl concentration for the evaluation of salt tolerance was 200 mmol·L-1.Membership function value and salt tolerance index were used to identify the most consistent salt tolerance traits.Leaf relative water content and photosynthesis were identified as reliable indicators for salt tolerance at the seedling stage.All considered traits related to salt tolerance indices were significantly and positively correlated with each other except for malondialdehyde.Cluster heat map analysis based on the morpho-physiological salt tolerance-indices clearly discriminated the 11 cotton genotypes into three different salt tolerance clusters.Cluster I represented the salt-tolerant genotypes(Z9807,Z0228,and Z7526)whereas clusters II(Z0710,Z7514,Z1910,and Z7516)and III(Z0102,Z7780,Z9648,and Z9612)represented moderately salttolerant and salt-sensitive genotypes,respectively.Conclusions:A hydroponic screening system was established.Leaf relative water content and photosynthesis were identified as two reliable traits that adequately represented the salt tolerance of cotton genotypes at the seedling growth stage.Furthermore,three salt-tolerant genotypes were identified,which might be used as genetic resources for the salt-tolerance breeding of cotton.展开更多
Background:Nitrogen(N)is important for improving various morphological and physiological processes of cotton but their contribution to fiber quality is still lacking.Aims:The current study aimed to explore the relatio...Background:Nitrogen(N)is important for improving various morphological and physiological processes of cotton but their contribution to fiber quality is still lacking.Aims:The current study aimed to explore the relationship between root morphology,subtending leaf physiology,and fiber quality of contrasting N-efficient cotton genotypes in response to N.Methods:We analyzed the above parameters of CCRI 69(N-efficient)and Xinluzao-30(XLZ-30,N-inefficient)under control(2.5 mmol·L^(-1))and high N(5 mmol·L^(-1))conditions.Results:The results showed that root morphological traits were increased in CCRI-69 under control conditions than high N.Subtending leaf morphology,chlorophyll and carotenoid contents,free amino acids,and soluble proteins were higher under high N as compared with the control.However,soluble sugars,fructose,sucrose contents,and sucrose phosphate synthase were higher under control conditions than high N across the growth stages.Irrespective of the N conditions,all morphological and physiological traits of cotton subtending leaf were higher in CCRI-69 than XLZ-30.Except for fiber uniformity,fiber quality traits like fiber length,strength,micronaire,and elongation were improved under control conditions than high N.Between the genotypes,CCRI-69 had significantly higher fiber length,strength,micronaire,and elongation as compared with XLZ-30.Strong positive correlations were found between root morphology,soluble sugars,sucrose content,and sucrose phosphate synthase activity with fiber quality traits,respectively.Conclusions:These findings suggest that CCRI-69 performed better in terms of growth and fiber quality under relatively low N condition,which will help to reduce fertilizer use,the cost of production,and environmental pollution.展开更多
基金supported by the National Natural Science Foundation of China(32001481)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences+3 种基金the China Agriculture Research System,the National Modern Agricultural Industry Technology System of China(CARS-18–05)the Provincial Key R&D and Promotion Special Projects in Henan(232102110178)the Program for Key Areas of Science and Technology of Xinjiang Production and Construction Corps Third Division and Tumsuk City(KY2021GG08)the Central Public-interest Scientific Institution Basal Research Fund(1610162023019)。
文摘Background Ensuring that seeds germinate and emerge normally is a prerequisite for cotton production,esp.in areas with salinized soil.Priming with mepiquat chloride(MC)can promote seed germination and root growth under salt stress,but its mechanism has not been fully elucidated.In this study,physiological and biochemical experiments revealed that MC-priming promotes the tolerance of cotton seeds to salt stress by increasing the ability of antioxidant enzymes related to the ascorbate-glutathione(AsA-GSH)cycle to scavenge reactive oxygen species(ROS).Results Results revealed that treatment with inhibitors of abscisic acid(ABA)and γ-aminobutyric acid(GABA)biosynthesis reduced the positive effects of MC-priming.Similarly,MC-priming increased the contents of ABA and GABA under salt stress by stimulating the expression levels of GhNCED2 and GhGAD4 and the activity of calmodulin-binding(CML)glutamate decarboxylase(GAD).Further analysis showed that an inhibitor of ABA synthesis reduced the positive impacts of MC-priming on the content of GABA under salt stress,but the content of ABA was not affected by the GABA synthesis inhibitor.Furthermore,a multi-omics analysis revealed that MC-priming increased the abundance and phosphorylation levels of the proteins related to ABA signaling,CML,and Ca^(2+)channels/transporters in the MC-primed treatments,which resulted in increased oscillations in Ca^(2+)in the MC-primed cotton seeds under salt stress.Conclusion In summary,these results demonstrate that MC-mediated ABA signaling operates upstream of the GABA synthesis generated by GAD by activating the oscillations of Ca^(2+)and then enhancing activity of the AsA-GSH cycle,which ensures that cotton seeds are tolerant to salt stress.
文摘【目的】综合评价棉花品种(系)出苗期耐冷性,建立可靠评价模型,筛选鉴定指标,为耐冷品种选育鉴定提供简便有效的评价方法。【方法】以200份陆地棉品种(系)为试验材料,设恒定低温、昼夜变温和适宜温度3个处理,测定其出苗率、下胚轴长、根长、百粒重等指标,采用耐冷系数差异分析、频次分析、降幅分析、主成分分析、聚类分析和多元回归分析等方法,对群体进行耐冷型划分,并建立耐冷性评价模型和确定鉴定指标。【结果】各指标在适宜温度下变异幅度较小,变异系数为3.12%—18.89%,各品种(系)出苗率在85.00%以上,具有较高的生活力,可用于后续耐冷性分析。在低温胁迫下群体内各指标变异幅度增大,为7.14%—108.33%,在恒定低温和昼夜变温下,变幅最大的指标依次为根长和萌发指数。主成分分析将14个低温相关指标和百粒重转换为6个相互独立的综合指标,代表了全部数据74.98%的信息量。利用隶属函数法计算综合耐冷评价值(D),并对其进行聚类分析,按照耐冷性强弱将200份陆地棉品种(系)划分为5类,第Ⅰ类群属于强耐冷型共2份,第Ⅱ类群属于耐冷型共42份,第Ⅲ类群属于中耐冷型共69份,第Ⅳ类群属于较敏感型共83份,第Ⅴ类群属于敏感型共4份,其中,新陆中16号为耐冷性最强的品种。采用多元回归分析方法,建立棉花出苗期耐冷性预测模型为Y=-4.10+0.58 X 4+0.40 X 14+0.32 X 1+0.22 X 5(R 2=0.92),筛选出4个耐冷性鉴定指标,分别为恒定低温下的棉苗总长、出苗率、干物重和昼夜变温下的萌发率。田间早播试验中各品种(系)的出苗率,与室内试验结果基本一致。【结论】采用恒定低温和昼夜变温处理结合多元统计分析方法对棉花出苗期耐冷性评价是可行的,恒定低温下的棉苗总长、出苗率、干物重和昼夜变温下的萌发率,可作为鉴定指标。
基金National key R&D Plan(No.2017YFD0201900,2017YFD0101600)State Key Laboratory of Cotton Biology Fund(CB2016C14)
文摘Background: Large quantities of nitrogen (N) fertilizer applied to cotton cropping systems support high yields but cause adverse environmental impacts such as N20 emission and water eutrophication. The development of cotton cultivars with higher N use efficiencies suitable for low-N conditions is therefore important for sustainable production. In this study, we evaluated 100 cotton genotypes in 2016 for N use efficiency and related traits at the seedling stage. Methods: Sand culture experiment was conducted with low N levels (0.01 g.kg i) or normal N levels (0.1 g.kg i). We investigated plant height, SPAD value (soil plant analysis development chlorophyll meter), dry weight, N accumulation, N utilization efficiency, and N uptake efficiency. Through descriptive statistics, principal component analysis and heatmap clustering analysis, we confirmed the evaluation index system of N-efficient genotypes and the classification of N-efficient genotypes. Results: Significant differences were observed among N levels and genotypes for all agronomic traits and N levels. Coefficients of variation varied greatly and ranged from 6.7N28.8 and 7.4N20.8 under low-N and normal-N treatment, respectively. All traits showed highly significant positive correlations with each other, except SPAD value. The principal components under both N levels were similar, showing that total dry weight, aboveground dry weight, total N accumulation, and N uptake efficiency were important components. We confirmed these four traits as suitable screening indexes for low N tolerance. Based on the results of heatmap clustering and scatter diagram analysis of N efficiency value, 10 genotypes were found low-N tolerant, in which five varieties were inefficient under both low and normal N conditions, while four varieties were found efficient under low-N conditions but inefficient under normal-N conditions. Only one variety was efficient under both low and normal-N conditions. Meanwhile, 20 genotypes were identified as low-N sensitive ones, in which 19 genotypes were inefficient under low-N conditions but efficient under normal-N conditions, one variety was inefficient under both low and normal-N conditions. Conclusion: We preliminarily identified Kashi as a low-N tolerant and N-efficient cotton genotype, and CCRI 64 as a low- N sensitive and N-inefficient cotton genotype. Further studies should be carried out to verify the yield and heritability effect of specific genotypes in the field.
基金supported by National Key R&D Program(2017YFD0101600)State Key Laboratory of Cotton Biology(CB2019C17)。
文摘Background:Salt stress significantly inhibits the growth,development,and productivity of cotton because of osmotic,ionic,and oxidative stresses.Therefore,the screening and development of salt tolerant cotton cultivars is a key issue towards sustainable agriculture.This study subjected 11 upland cotton genotypes at the seedling growth stage to five different salt concentrations and evaluated their salt tolerance and reliable traits.Results:Several morpho-physiological traits were measured after 10 days of salinity treatment and the salt tolerance performance varied significantly among the tested cotton genotypes.The optimal Na Cl concentration for the evaluation of salt tolerance was 200 mmol·L-1.Membership function value and salt tolerance index were used to identify the most consistent salt tolerance traits.Leaf relative water content and photosynthesis were identified as reliable indicators for salt tolerance at the seedling stage.All considered traits related to salt tolerance indices were significantly and positively correlated with each other except for malondialdehyde.Cluster heat map analysis based on the morpho-physiological salt tolerance-indices clearly discriminated the 11 cotton genotypes into three different salt tolerance clusters.Cluster I represented the salt-tolerant genotypes(Z9807,Z0228,and Z7526)whereas clusters II(Z0710,Z7514,Z1910,and Z7516)and III(Z0102,Z7780,Z9648,and Z9612)represented moderately salttolerant and salt-sensitive genotypes,respectively.Conclusions:A hydroponic screening system was established.Leaf relative water content and photosynthesis were identified as two reliable traits that adequately represented the salt tolerance of cotton genotypes at the seedling growth stage.Furthermore,three salt-tolerant genotypes were identified,which might be used as genetic resources for the salt-tolerance breeding of cotton.
基金the financial support from the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences(CAAS),Cotton Research Institute,CAAS,Central Level Public Welfare Scientific Institutes Basic Research and Business Special Funding Project(Grant No.1610162021025)the State Key Laboratory of Cotton Biology,Institute of Cotton Research of CAAS(CB2021C10).
文摘Background:Nitrogen(N)is important for improving various morphological and physiological processes of cotton but their contribution to fiber quality is still lacking.Aims:The current study aimed to explore the relationship between root morphology,subtending leaf physiology,and fiber quality of contrasting N-efficient cotton genotypes in response to N.Methods:We analyzed the above parameters of CCRI 69(N-efficient)and Xinluzao-30(XLZ-30,N-inefficient)under control(2.5 mmol·L^(-1))and high N(5 mmol·L^(-1))conditions.Results:The results showed that root morphological traits were increased in CCRI-69 under control conditions than high N.Subtending leaf morphology,chlorophyll and carotenoid contents,free amino acids,and soluble proteins were higher under high N as compared with the control.However,soluble sugars,fructose,sucrose contents,and sucrose phosphate synthase were higher under control conditions than high N across the growth stages.Irrespective of the N conditions,all morphological and physiological traits of cotton subtending leaf were higher in CCRI-69 than XLZ-30.Except for fiber uniformity,fiber quality traits like fiber length,strength,micronaire,and elongation were improved under control conditions than high N.Between the genotypes,CCRI-69 had significantly higher fiber length,strength,micronaire,and elongation as compared with XLZ-30.Strong positive correlations were found between root morphology,soluble sugars,sucrose content,and sucrose phosphate synthase activity with fiber quality traits,respectively.Conclusions:These findings suggest that CCRI-69 performed better in terms of growth and fiber quality under relatively low N condition,which will help to reduce fertilizer use,the cost of production,and environmental pollution.