薏苡种质资源苗期抗旱性鉴定及抗旱指标筛选

发布时间：2018-03-16 00:16

  本文选题：薏苡　切入点：苗期抗旱性　出处：《中国农业科学》2017年15期 　论文类型：期刊论文

【摘要】：【目的】干旱是影响薏苡生产的重要非生物胁迫因素,鉴定薏苡种质资源的抗旱性,确定抗旱指标,筛选抗旱种质,促进薏苡产业发展。【方法】以50份薏苡种质为材料,设置正常供水和反复干旱2个处理,在旱棚内进行盆栽试验,测定干旱对幼苗存活率、株高、茎粗、叶长、叶宽、地上部鲜重、地上部干重、根长、根粗、根鲜重和根干重的影响;采用抗旱性度量值(D值)、综合抗旱系数(CDC值)、加权抗旱系数(WDC)、相关分析、频次分析、主成分分析、灰色关联度分析、隶属函数分析、聚类分析和逐步回归分析相结合的方法,对其进行苗期抗旱性鉴定及抗旱指标筛选。【结果】干旱胁迫对各指标均有极显著影响。相关分析表明,幼苗干旱存活率与茎粗、叶宽和根粗呈极显著正相关,与叶长、地上部鲜重、地上部干重、根长、根鲜重和根干重呈显著正相关,与株高呈不显著的正相关。频次分析表明,各指标对干旱胁迫反应的敏感程度依次为根干重、根鲜重、叶宽、根粗、根长、幼苗干旱存活率、地上部干重、茎粗、地上部鲜重、叶长和株高。主成分分析表明,6个主成分可代表薏苡抗旱性91.40%的原始数据信息量。基于D值、CDC值和WDC值的供试薏苡种质抗旱性排序相近。灰色关联度分析表明,各指标DC值与D值间的关联度大小依次为根干重、叶宽、根鲜重、茎粗、根粗、幼苗干旱存活率、根长、株高、地上部鲜重、地上部干重、叶长,这与各指标DC值与WDC值的密切程度基本吻合。根据D值进行聚类分析,可将供试薏苡种质划分为5个抗旱级别,其中Ⅰ级3份、Ⅱ级17份、Ⅲ级9份、Ⅳ级20份、Ⅴ级1份。除叶长、地上部鲜重、地上部干重和根干重外,其余指标的隶属函数值、CDC值、D值和WDC值均随抗旱级别的升高而增大。逐步回归分析表明,与D值密切相关的指标有幼苗干旱存活率、株高、叶宽、根长和根鲜重。【结论】苗期抗旱性强的薏苡种质yy18-1、yy14-3和yy13-1,可作为薏苡抗旱育种、抗旱机理及干旱调控缓解机制研究材料。幼苗存活率、株高、叶宽、根长和根鲜重可作为评价薏苡种质资源苗期抗旱性的指标性状。
[Abstract]:[objective] drought is an important abiotic stress factor affecting the production of Coix. The drought resistance of Coix lachryma germplasm resources was identified, the drought resistance index was determined, the drought resistant germplasm was screened, and the industry development of Coix lacryma was promoted. [methods] 50 Coix germplasms were used as materials. Two treatments, normal water supply and repeated drought, were used to test the survival rate of seedlings, plant height, stem diameter, leaf length, leaf width, fresh weight, dry weight, root length and root diameter. The effects of root fresh weight and root dry weight were analyzed by using drought resistance measure value D value, comprehensive drought resistance coefficient and CDC value, weighted drought resistance coefficient, correlation analysis, frequency analysis, principal component analysis, grey correlation analysis, membership function analysis, Cluster analysis and stepwise regression analysis were used to identify the drought resistance of seedlings and to screen drought resistance indexes. [results] drought stress had a significant effect on each index. Correlation analysis showed that seedling drought survival rate and stem diameter were significantly affected. Leaf width was positively correlated with root diameter, leaf length, shoot fresh weight, shoot dry weight, root length, root fresh weight and root dry weight, but not with plant height. The sensitivities of the indexes to drought stress were root dry weight, root fresh weight, leaf width, root diameter, root length, seedling drought survival rate, shoot dry weight, stem diameter and shoot fresh weight. Leaf length and plant height. Principal component analysis showed that the six principal components could represent the original data information of Coix seed drought resistance 91.40%. The order of drought resistance of Coix lachryma germplasm based on D value and WDC value was similar. The grey correlation analysis showed that the drought resistance of Coix lachryma germplasm was similar. The correlation degree between DC value and D value was root dry weight, leaf width, root fresh weight, stem diameter, root diameter, seedling drought survival rate, root length, plant height, aboveground fresh weight, shoot dry weight, leaf length. According to the cluster analysis of D value, Coix seed germplasm can be divided into 5 drought-resistant grades, of which 3 are 鈪，

本文编号：1617474