为探究盐胁迫下水稻地上部和根部Na^(+)、K^(+)含量和分布对其生物量累积和苗期耐盐性的影响,利用125 mmol/L Na Cl对51份不同类型水稻种质资源进行胁迫处理,测定5个形态学指标:耐盐级别、相对根长、相对地上部干重、相对根干重和地上...为探究盐胁迫下水稻地上部和根部Na^(+)、K^(+)含量和分布对其生物量累积和苗期耐盐性的影响,利用125 mmol/L Na Cl对51份不同类型水稻种质资源进行胁迫处理,测定5个形态学指标:耐盐级别、相对根长、相对地上部干重、相对根干重和地上部含水量;6个离子指标:地上部Na^(+)含量、根系Na^(+)含量、地上部K^(+)含量、根系K^(+)含量、地上部Na^(+)/K^(+)和根系Na^(+)/K^(+),共11个耐盐相关指标。在主成分分析基础上,利用隶属函数和标准差系数赋予权重法获得水稻苗期耐盐性综合评价值(D值)。利用特异引物扩增SKC1基因编码区进行测序、比对和单倍型分析。结果表明:除相对根长外,地上部Na^(+)含量与其余4个形态学指标呈极显著负相关,耐盐级别与地上部Na^(+)含量、根系Na^(+)含量和地上部Na^(+)/K^(+)均呈极显著负相关,耐盐级别、相对地上部干重、相对根干重、地上部含水量4个指标两两之间均呈极显著正相关。利用SPSS主成分分析将11个单项指标转换为4个主成分,累计贡献率达82.093%。依据PC1中各指标的载荷系数,筛选出相对地上部干重、耐盐级别、相对根干重、地上部Na^(+)含量、地上部Na^(+)/K^(+)和根系Na^(+)含量6个重要指标;结合综合评价D值与这6个指标的线性回归分析,发现耐盐级别和地上部Na^(+)/K^(+)的系数较大,分别是影响水稻苗期耐盐性的形态学和离子平衡关键因子。通过对51份水稻种质资源SKC1编码区序列比对,共检测到9种不同的单倍型。其中源于越光的单倍型(Hap1)为粳稻种质资源的优势等位基因;源于Nona Bokra的单倍型(Hap7)为籼稻和Aus的优势等位基因。本研究结果可从离子平衡层面为耐盐水稻资源筛选与鉴定提供理论依据。展开更多
Rice is sensitive to salinity stress at both the seedling and reproductive stages.The present study used 145 rice genotypes comprising of 100 landraces and 45 advanced breeding lines collected from different regions o...Rice is sensitive to salinity stress at both the seedling and reproductive stages.The present study used 145 rice genotypes comprising of 100 landraces and 45 advanced breeding lines collected from different regions of India.These genotypes were evaluated in hydroponics under control[electrical conductivity(ECe)~1.2 dS/m]and saline(ECe~10.0 dS/m)environments along with susceptible(IR29)and tolerant(FL478)checks.The stress susceptibility index for eight morphophysiological traits was estimated.Analysis of variance showed significant differences among the genotypes for all the parameters studied in control,stress and relative stress conditions.We identified 3 landraces(Kuttimanja,Tulasimog and IET-13713I)as tolerant and 14 lines as moderately tolerant to salt stress.Strong correlations in the morphological(root and shoot lengths)and physiological traits(shoot Na^(+),Ca^(2+)and Mg^(2+)contents,and Na^(+)/K^(+)ratio)were observed under all the conditions.The hierarchical cluster analysis grouped the genotypes into five clusters,among which cluster Ⅱ comprised salt-tolerant lines.Haplotyping of Saltol region using 11 simple sequence repeat markers on 17 saline tolerant and moderately tolerant lines was conducted.Markers AP3206F,RM10793 and RM3412b,located close to SKC1 gene(11.23‒12.55 Mb),displayed diverse allelic variations and they were not related to the FL478 type.In this region,tolerant lines like Kuttimanja,IET-13713I and Tulasimog have new alleles.As a result,these lines may be suitable candidates for novel genomic regions governing rice salinity tolerance.Salt-tolerance ability of Kuttimanja,Tulasimog and IET-13713I was validated in two years in three salinity stress environments.These promising lines can be used in breeding programs to broaden the genetic base of salinity tolerance in rice,and it may help to dissect key genomic regions responsible for salinity tolerance.展开更多
文摘为探究盐胁迫下水稻地上部和根部Na^(+)、K^(+)含量和分布对其生物量累积和苗期耐盐性的影响,利用125 mmol/L Na Cl对51份不同类型水稻种质资源进行胁迫处理,测定5个形态学指标:耐盐级别、相对根长、相对地上部干重、相对根干重和地上部含水量;6个离子指标:地上部Na^(+)含量、根系Na^(+)含量、地上部K^(+)含量、根系K^(+)含量、地上部Na^(+)/K^(+)和根系Na^(+)/K^(+),共11个耐盐相关指标。在主成分分析基础上,利用隶属函数和标准差系数赋予权重法获得水稻苗期耐盐性综合评价值(D值)。利用特异引物扩增SKC1基因编码区进行测序、比对和单倍型分析。结果表明:除相对根长外,地上部Na^(+)含量与其余4个形态学指标呈极显著负相关,耐盐级别与地上部Na^(+)含量、根系Na^(+)含量和地上部Na^(+)/K^(+)均呈极显著负相关,耐盐级别、相对地上部干重、相对根干重、地上部含水量4个指标两两之间均呈极显著正相关。利用SPSS主成分分析将11个单项指标转换为4个主成分,累计贡献率达82.093%。依据PC1中各指标的载荷系数,筛选出相对地上部干重、耐盐级别、相对根干重、地上部Na^(+)含量、地上部Na^(+)/K^(+)和根系Na^(+)含量6个重要指标;结合综合评价D值与这6个指标的线性回归分析,发现耐盐级别和地上部Na^(+)/K^(+)的系数较大,分别是影响水稻苗期耐盐性的形态学和离子平衡关键因子。通过对51份水稻种质资源SKC1编码区序列比对,共检测到9种不同的单倍型。其中源于越光的单倍型(Hap1)为粳稻种质资源的优势等位基因;源于Nona Bokra的单倍型(Hap7)为籼稻和Aus的优势等位基因。本研究结果可从离子平衡层面为耐盐水稻资源筛选与鉴定提供理论依据。
基金the Department of Science and Technology,Government of India(Grant No.CRG/2020/003078).
文摘Rice is sensitive to salinity stress at both the seedling and reproductive stages.The present study used 145 rice genotypes comprising of 100 landraces and 45 advanced breeding lines collected from different regions of India.These genotypes were evaluated in hydroponics under control[electrical conductivity(ECe)~1.2 dS/m]and saline(ECe~10.0 dS/m)environments along with susceptible(IR29)and tolerant(FL478)checks.The stress susceptibility index for eight morphophysiological traits was estimated.Analysis of variance showed significant differences among the genotypes for all the parameters studied in control,stress and relative stress conditions.We identified 3 landraces(Kuttimanja,Tulasimog and IET-13713I)as tolerant and 14 lines as moderately tolerant to salt stress.Strong correlations in the morphological(root and shoot lengths)and physiological traits(shoot Na^(+),Ca^(2+)and Mg^(2+)contents,and Na^(+)/K^(+)ratio)were observed under all the conditions.The hierarchical cluster analysis grouped the genotypes into five clusters,among which cluster Ⅱ comprised salt-tolerant lines.Haplotyping of Saltol region using 11 simple sequence repeat markers on 17 saline tolerant and moderately tolerant lines was conducted.Markers AP3206F,RM10793 and RM3412b,located close to SKC1 gene(11.23‒12.55 Mb),displayed diverse allelic variations and they were not related to the FL478 type.In this region,tolerant lines like Kuttimanja,IET-13713I and Tulasimog have new alleles.As a result,these lines may be suitable candidates for novel genomic regions governing rice salinity tolerance.Salt-tolerance ability of Kuttimanja,Tulasimog and IET-13713I was validated in two years in three salinity stress environments.These promising lines can be used in breeding programs to broaden the genetic base of salinity tolerance in rice,and it may help to dissect key genomic regions responsible for salinity tolerance.
