20个水稻引进资源的花药开裂及苗期耐热性评价

对20个从USDA引进的水稻资源进行了苗期耐热性鉴定和与开花期耐热性紧密相关的花药开裂性状测定。鉴定结果表明,20个资源苗期高温处理后恢复7 d的相对幼苗成活率为83.23%~100%,恢复10 d的相对幼苗成活率为68.18%~100%。其中N22、AD-1140、IR 9403-3-1-1和IR 4427-51-6-3具有较强的苗期耐热性。引进资源的花药基部开裂长度为234.9~559.0μm,花药总长度为1570.0~2351.7μm,其中IR 2006-p-P12-12-3-2和N22的花药基部开裂长度分别最短和最长。20个资源的花药基部开裂长度和高温胁迫后恢复7 d及10 d的相对幼苗成活率之间均存在极显著正相关,花药长度和高温胁迫后恢复7 d及10 d的相对幼苗成活率没有相关性。系谱分析表明,部分引进资源间具有较近的亲缘关系。花药基部开裂长度作为水稻耐热性的评价指标还需要进行进一步的深入研究。

Analyzing of Length Dehiscence at Basal Part of Thecae and Heat Resistance during Seedling Stage of 20 Introduced Rice Germplasms

Heat tolerance of 20 rice germplasms introduced from USDA were evaluated at seedling stage based on relative survival rate of seedling. The length of dehiscence at the basal part of thecae (BDL) which significant related with heat resistance on heading time and the length of anther (AL) were measured during flowering. After treated with heat and then recovered for 7 days, the relative survival rate of seedling of those germplasms was from 83.23 to 100%. When they recovered for 10 days after heat treatment, the relative survival rate of seedling was from 68.18 ~ 100%. N22, AD-1140, IR9403-3-1-1 and IR4427-51-6-3 showed high heat tolerance at seedling stage. BDL and AL of germplasms were ranged from 234.9 to 559.0 um and 1570.0 to 2351.7 um, respectively. Significant correlation between BDL and relative survival rate of seedling was found. The results indicated that the BDL also might be considered as the index of heat tolerance during seedling stage and deeply research is necessary in the future.