不同棉花种质资源耐热性鉴定

Identification for the Thermotolerance of Different Germplasm in Cotton

随着全球气候变暖,高温胁迫已经成为影响棉花产量的主要因素之一。中国棉花种植区,在7月和8月棉花花铃高峰期经常出现周期性极端高温胁迫,导致蕾铃脱落,降低了产量,因此棉花耐热性种质的筛选迫在眉睫。本试验在新疆吐鲁番自然高温条件下,调查200份不同棉花种质资源的脱落率、花粉活力、叶片萎蔫程度、花粉形态、不孕子率等田间性状。然后选择29份不同耐热性种质在河南安阳种植,调查30、35、40、45和50℃离体培养条件下的花粉萌发率。不同耐热性种质资源在自然高温条件下的鉴定指标和室内离体培养花粉萌发率存在着极显著的差异。而且不同鉴定指标间也存在着不同的相关性。结合田间调查结果和花粉离体培养萌发率,将29份种质划分为耐高温型、较耐高温型、高温较敏感型和高温敏感型种质,并初步确定了耐热性的鉴定指标。

With global climate been warming,heat stress has became a main factor influencing cotton product around the world. In cotton growing areas of China, especially in Yangtze River valley,unexpected periodic extreme high temperature usually occurred in the period of full florescence and boll setting,and this resulted in higher bud and boll abscission rates and lower lint yields. Hence,screening of heat resistant cotton germplasm is extremely ur- gent. In this study, we planted 200 different thermotolerance cotton germplasms in Tulufan of Xinjiang province loca- ted in west of china. We investigated the bud and boll abscission rates, pollen vitality,leaf wilting, pollen morpholo- gy,infertility seed rates and so on. And then 29 germplasms with different heat tolerance were growed in Anyang of Henan. The pollen germination rate in vitro at 30 ℃ ,35 ℃ ,40 ℃ ,45 ℃ ,and 50 ℃ were investigated respectively. There were significant differences in field index and pollen germination rate among different thermotolerance cotton germplasms. Meanwhile there were different correlation in the ten identify index. Based on the pollen germination rate in vitro and the field index of heat tolerance,29 germplasms were fell into four types including heat tolerance line, moderately heat tolerance line, heat suseptible line, and moderately susceptible line. And the field identification indexes for the thermotolerance were confirmed.