玉米温敏自交不亲和系的鉴定与生态学机制分析

Identification and ecological analysis of a new thermo-sensitive genic self-incompatibility line in maize

在玉米繁殖过程中发现了一种生态自交不亲和材料HE 97,为了证明其不亲和类型及其生态学机制,通过2 a田间分期播种和花丝切片观察,对该材料的自交不亲和性进行了研究.结果表明,HE 97的自交不亲和性主要受温度影响,表现为高温自交亲和,低温自交不亲和,亲和性转换的敏感时期是雄穗的小花分化期/雌穗生长锥伸长期,临界温度为20-24℃.花粉在其相同基因型花丝上不能萌发可能是导致HE 97自交不亲和的主要原因.

The present study describes a novel ecological self-incompatibility （SI） line, HE 97, in maize, which was found in the propagation of inbred line in the field, and its ecological mechanism was analyzed. It was identified through sowing at different stages for two years （2004 and 2005 ） , and observing the pollen tubes in the selfing and intercross silks using microscope. The results demonstrated that the daily minimum temperature was the main environmental factor affecting the characteristics of the SI line. It expressed complete self-compatibility under high temperature but self-incompatibility under low temperature, and the temperature boundary of self-compatible transition was 20 -24 ℃ at the floret differentiation of the staminate inflorescence or the elongation stage of pistil. Additionally, the self-incompatibility of the SI line was mainly caused by the fact that pollen germination was inhibited by stigma or that the pollen tube could not growth in silk.