利用花生RIL群体进行芽期耐寒性遗传特性分析

花生是我国分布极广的重要油料和经济作物，低温寒害是高纬度高海拔产区严重限制其生产发展的关键逆境因素，其中发芽期的危害最为普遍和严重。为深入研究花生芽期耐寒性遗传特性，本研究以耐寒性强的品种和耐寒性弱的品种杂交［HY44×DF12（HD-RIL）和YZ9102×XZ68-4（YX-RIL）］构建了两个重组自交系（RIL）群体，利用主基因+多基因混合遗传模型对2个RIL群体低温胁迫后的相对发芽率进行遗传特性分析。结果表明，2个RIL群体的耐寒性在2020年海南乐东（E1）环境中均表现为由3对加性上位性主基因+加性多基因控制，HD-RIL和YX-RIL的主基因遗传率分别为86.72%、91.46%，在2021年山西汾阳（E2）环境中均表现为由2对显性上位主基因+加性多基因控制，主基因遗传率分别为74.35%、79.56%；HD-RIL群体在2021年海南南滨（E3）环境中与YX-RIL群体在2020年山西汾阳（E4）环境中耐寒性均表现为由2对累加作用的主基因+加性多基因控制，主基因遗传率分别为64.20%、59.05%。本研究结果为深入开展花生芽期耐寒性分子机制研究、提高耐寒性分子育种效率提供了重要的理论基础。

Genetic Analysis of Cold Tolerance at Germination Stage by RIL Population of Peanut

Peanut is an important oil and cash crop widely distributed in China. Low temperature stress is a key obstacle that severely restricts its production development in high latitude or altitude producing areas. The damage is the most prevalent and serious in seed germination stage. Therefore， it is of great significance to deeply study the genetic characteristics of cold tolerance in seed germination stage of peanut. In this study， two Recombinant Inbred Line （RIL） populations were constructed by crossing varieties with strong cold tolerance and varieties with weak cold tolerance ［HY44×DF12 （HD-RIL） and YZ9102×XZ68-4 （YX-RIL）］. The genetic characteristics of the relative germination rate in two RIL populations under low temperature stress were analyzed by using the major gene plus additive polygene mixed genetic model. The results showed that under E1（Ledong， Hainan in 2020）， the cold tolerance traits in the two RIL populations were controlled by three major genes plus additive polygenes with additive-epistatic effect， with the heritability of major genes accounting for 86.72% （HD-RIL） and 91.46% （YX-RIL）. Under E2（Fenyang， Shanxi in 2021）， the cold tolerance was controlled by two major genes plus polygenes with dominant-epistatic effect. The heritability of major genes was 74.35% and 79.56%. The cold tolerance traits for HD-RIL population under E3（Nanbin， Hainan in 2021） and YX-RIL population under E4（Fenyang， Shanxi in 2020） were controlled by two major genes plus additive polygenes with accumulative effect. The heritability of major genes was 64.20% and 59.05%， respectively. The results of this study will provide an important theoretical basis for further research on the molecular mechanism of cold tolerance in seed germination period and improve the efficiency in cold tolerance molecular breeding.