粳稻种质资源苗期根系形态特征与耐盐性相关分析  

Correlation between root morphological characteristics of japonica rice germplasm and salt tolerance at seedling stage

作　　者：王娜[1] 陈亚萍[1] 田蕾[1] 张得雯 王瑞智[1] 杨苗[1] 李培富[1] 

机构地区：[1]宁夏大学农学院,宁夏银川750021

出　　处：《广东农业科学》2015年第10期1-10,共10页Guangdong Agricultural Sciences

基　　金：国家自然科学基金(31401361);宁夏农业育种专项--水稻新品种选育(分子育种技术的应用研究)

摘　　要：采用国际水稻所标准营养液培养57个粳稻种质资源,在发芽14d后对各种质资源进行盐胁迫（125mmol/L NaCl）处理,于盐胁迫后3、6d分别取样进行根系扫描;盐胁迫6d后,叶片盐害症状明显,根据盐害症状评价水稻耐盐级别,利用耐盐级别将各种质资源初步分为耐盐组、中度耐盐组和盐敏感组3组。以耐盐级别作为衡量水稻耐盐性的依据,运用多种统计学方法对57个粳稻种质资源苗期的耐盐性进行综合评价及分类,并分析典型耐盐和盐敏感种质资源根系形态特征。结果表明,耐盐级别与根总表面积,平均直径,根系总体积,0.5-1.0mm直径根的总长度、总表面积和总体积均呈极显著正相关;与总根长、根尖数、分叉数呈显著正相关;聚类分析结果表明,各类群的种质资源无明显的地域性分布,Ⅰ、Ⅱ类群分别为典型的盐敏感和耐盐类群,Ⅲ、Ⅳ类群为中间型种质的混合类群;通过主成分分析将14个根系指标转换为2个主成分,应用隶属函数和权重,获得了客观评价粳稻种质资源耐盐性的综合评价值（D值）。将D值和各单项指标进行逐步回归分析,获得了1个最优回归方程。分别选取D值最高和最低的5份种质资源于苗期盐胁迫后3、6d对根系指标进行差异显著性分析,结果表明：两组种质资源盐胁迫后3d的根系指标大都差异较小;盐胁迫后6d的根系指标除平均直径和根尖数外,均达到显著差异水平。水稻苗期的根系对盐胁迫非常敏感,且在耐盐性不同的种质间差异显著,可以作为快速鉴定粳稻种质资源苗期耐盐性的重要指标。Fifty-seven japonica rice germplasm resources were cultured in IRRI standard nutrient solution,in which 125 mmol/L NaCl was added 14 days after germination.After three days and six days of salt stress,roots of each rice germplasm were sampled for scanning and analyzing.The visual foliar symptom was used to evaluate the salt tolerance score（STS）of each rice germplasm after six days.According to the STS,these rice germplasm resources were divided into three groups,including salt tolerant group,moderately salt tolerance group and salt sensitive group.Some statistical methods were used to evaluate the salt tolerance of these 57 rice germplasm resources and the root morphological characteristics of typical salt tolerant and salt sensitive rice germplasm resources were analyzed.The results showed that salt tolerance score was significantly positive correlated with total root surface area,root average diameter,root volume and total length,total surface area,total volume of 0.5-1.0 mm diameter roots;was positive correlated with root total length,root tip number and root forks number.The cluster analysis showed that there was no obvious regional distribution among these four germplasm groups.The groupⅠand group Ⅱ were typical salt sensitive and salt tolerant groups and the group Ⅲ and group Ⅳ were mixed with intermediate germplasm.With the principal component analysis,14 root single indexes could be converted to two principal components.An objective comprehensive evaluation value（D value）of salt tolerance was obtained using membership function with index weight method.A mathematical evaluation model was established by means of regression analysis.The five highest and lowest of the D values of germplasm resources were selected to carry out difference analysis.The results showed that most of these root indexes measured after stress for three days had no significant difference among these two types;and for the low D value type,most of these root indexes except for root average diameter and root tip number mea

关 键 词：水稻 苗期耐盐性 耐盐级别 根系形态特征 综合评价 

分 类 号：S511.22[农业科学—作物学]