东北大豆RIL群体不同生育时期倒伏的农艺性状多因子分析

Agronomic Trait Multi-factor Analysis of Lodging at Different Growth Periods in a Soybean RIL Population from the Northeast of China

茎秆强度、株高、主茎节数、节间长度、茎叶重、根重等是评价大豆倒伏的重要相关农艺性状,为综合分析这些性状,以便揭示大豆倒伏的遗传机理,本研究以地理远缘重组自交系(RIL)群体为试材,在发生倒伏的3个主要时期,调查倒伏相关农艺性状和家系倒伏情况,分析不同生育时期主要农艺性状与田间实际倒伏的关系。结果表明:RIL群体在R4期开始发生倒伏,不同发育时期各主要农艺性状与家系倒伏情况相关性不同,R4期至R8期影响倒伏的主要农艺性状经历了由茎重向株高、节间长度和茎秆强度等性状的演变。本研究使用多个农艺性状设计了8个大豆倒伏评价指数综合分析RIL群体田间倒伏情况,各倒伏指数在各生育时期均与家系倒伏情况呈极显著正相关,且相关性均高于其它单一性状与实际倒伏情况的相关性。其中,倒伏指数[(节间长度×茎重)/茎杆强度]与实际倒伏情况相关性最高,且仅用最少农艺性状代替直观观察到的倒伏情况,可作为倒伏研究的一个复合评价指标用于对RIL群体进行抗倒伏QTL定位,为将来大豆抗倒伏优异等位基因的挖掘提供技术手段。

Stem strength, plant height, node number of main stem, internode length, shoot weight, and root weight are important agronomic traits relevant to soybean lodging. In order to comprehensively analysis these traits and reveal the lodging mechanism of soybean, this research used the geographic distant recombinant inbred lines population(RIL) to investigate the agronomic traits related to lodging and the lodging at the three main periods when lodging occurred. The relationship between main agronomic traits and the actual lodging at different development stages were analyzed. The results showed that the RIL population at R4 period began to lodging. The correlation at different development periods between each main agronomic trait and lodging situation of the family lines were different. The main agronomic traits affecting the lodging from R4 period to R8 period experienced an evolution from stem weight to plant height, internode length and stem strength. In this study, we designed eight lodging evaluation indexes using multiple agronomic characters to analyze comprehensively RIL field lodging situation. The lodging indexes at each growth period were extremely significantly positive relative with lodging situation of the family lines and the correlations were higher than that of any other single character. A lodging index [(inter-node length×stem weight)/stem strength] showed the highest correlation with actual lodging situation. It can replace the directly observation of the lodging situation with less agronomic traits and in the same time using a composite index in lodging resistance QTL mapping based on RIL population in order to provide a technological approach in the future to mine excellent alleles related to lodging resistance in soybean.