薏苡种质资源成株期抗旱性鉴定及抗旱指标筛选

以50份薏苡种质为材料,设置正常灌水和干旱胁迫2个处理,测定株高、茎粗、分枝数、主茎节数、分蘖数、单株粒数、单株粒重、千粒重和产量,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,对其进行成株期抗旱性鉴定及抗旱指标筛选。结果表明,各指标对干旱胁迫的反应及关联程度各异。6个公因子可代表薏苡抗旱性90.80%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。供试薏苡种质产量抗旱系数(Y值)与D值、CDC值和WDC值均呈极显著正相关。筛选出成株期抗旱性强的薏苡种质有yy18-1、yy03-8和粱丰薏14-2。分蘖数、单株粒重和千粒重可作为薏苡种质资源成株期抗旱性评价的直观指标。

Identification and Indices Screening of Drought Resistance at Adult Plant Stage in Job’s Tears Germplasm Resources

Drought is one of the major problems for Job’s tears production. The plant height, culm diameter, branch number, culm node number, tiller number, grainnumberperplant, grain weight per plant, 1000-grain weight, and yield of 50 accessions of Job’s tears germplasm were measured in normal irrigation and drought stress treatments. Drought resistance comprehensive evaluation value (D value), comprehensive drought resistance coefficient (CDC value), and weight drought resistance coefficient (WDC value) were used in correlation analysis, frequency analysis, principal component analysis, grey relational analysis, subordinate function analysis, clustering analysis, and stepwise regression analysis to identify and screen drought resistance indices at adult plant stage of tested Job’s tears germplasm. There were differences in response to drought stress and correlations between all indices. Six common factors could represent 90.80% of the original information of Job’s tears drought resistance data. The ranks of drought resistance of tested Job’s tears germplasm based on D value, CDC value, and WDC value were similar. The yield drought resistance coefficient (Y value) of tested Job’s tears germplasm had significant and positive correlation with D value, CDC value, and WDC value. Liangfengyi 14-2, yy03-8, and yy18-1 were identified as drought resistant Job’s tears germplasm at adult plant stage. Tiller number, grain weight per plant, and 1000-grain weight could be used as the intuitive identification indices for drought resistance in Job’s tears germplasm resources at adult plant stage.