黄瓜芽期耐热相关指标的筛选及预测方程的建立

Screening of Relevant Indexes of Hot Tolerance at Seed Germination Stage and Establishment of Forecast Equation for Cucumber

为了研究不同黄瓜材料芽期耐热性的差异,筛选出耐热性鉴定的形态指标,提高耐热性黄瓜的育种效率。以6种不同耐热性黄瓜为试验材料,在不同温度下测定芽苗形态指标,并进行主成分分析和回归分析。结果表明:38℃高温发芽条件下,全鲜质量(X1)、去子叶鲜质量(X2)、下胚轴长(X3)、根长(X4)、侧根数(X5)、发芽指数(X6)、活力指数(X7)与黄瓜耐热性相关,可作为黄瓜耐热性材料的筛选指标;主成分分析表明,第一、二、三主成分对耐热性评价贡献率分别为83.75%、10.68%和4.16%,累计贡献率达到98.59%;通过逐步回归建立黄瓜芽期耐热性预测方程Y=-0.6245-0.4828X5+1.2072X7,将该方程用于黄瓜耐热性评价的结果与田间表现基本一致,可作为黄瓜耐热性评价和预测的依据。

In order to study the difference of hot tolerance of different cucumber cultivars,screen the morphological indexes of hot-tolerance identification for cucumber,improve breeding efficiency,we used the 6 hot-tolerance known straits of cucumber as the test material.The morphology index of sprouts was screened at different temperature.The principal component analysis and regression analysis were made according to these indexes.The results showed that the whole-plant fresh weight(X1),fresh weight of plant without cotyledon(X2),hypocotyl length(X3),root length(X4),lateral root number(X5),germination index(X6),and vigor index(X7)were related to the hot tolerance of cucumber under the condition of germination at 38℃,which were suggested to be the reliable screening indexes to identify hot-tolerance of cucumber.The principal component analysis showed that the first,second and third principal components contributed 83.75%,10.68%and 4.16%to the hot-tolerance of cucumber respectively,and the cumulative contribution rate reached 98.59%.By gradually regression,the forecast equation Y=-0.6245-0.4828X5+1.2072X7 for cucumber germination was established.The results of the evaluation of cucumber hot-tolerance were basically the same as those of field performance,which can be used as the basis for cucumber hot-tolerance evaluation and prediction.