花生重组近交系(RIL)根部性状的遗传分析

Genetic Analysis of Root Characters in Recombination Inbred Lines(RIL) of Peanut(Arachis hypogaea L.)

利用花生RIL群体．分析了主根长、侧根数、根基粗（1cm和3cm处）、根体积、主根鲜重、干重、侧根鲜重和干重、主侧根瘤数等11个花生根部性状的遗传力，估算基因对数及性状间的相互关系，根据偏度系数（g1）和峰度系数（g2）的估算控制性状基因互作情况。结果表明：在11个研究性状中，有6个性状在2个亲本间差异显著或极显著。但不论性状在亲本间的差异显著与否，在RIL群体中基因型间的性状差异均表现为连续变异和明显的超亲分离。同时主根粗（1cm）和主根长的变异系数较小，分别为11．27％和11．218％。11个花生根部性状都是受多基因控制的数量性状，如影响侧根根瘤数、侧根鲜重和侧根干重的基因均在10对左右；而其它性状的基因估计在5—7对左右，尤其是控制侧根数的基因最少为5对左右。而在RIL群体中．除侧根干重的遗传力最高．达0．569，其次是侧根根瘤和侧根数分别达0．545和0．542外，其它性状的遗传力均较低。同时控制主根长和主根粗（1cm）的基因间存在重叠作用；而控制侧根根瘤、侧根鲜重和侧根干重基因间存在互作，表现为互补作用；控制其它性状的基因间互补或重叠作用不明显或者不存在。主根干重和侧根干重与根体积、主根粗（1cm）和主根粗（3cm）显著相关，根体积与主根粗（3cm）极显著相关，主根鲜重和侧根鲜重与根体积的相关表现不一致。

With a RIL population culture in peanut （Arachis hypogaea L. ）, the heritability analysis of eleven quantitative traits of root,for example ,length of axial root, number of lateral root, thickness of root base （ 1 cm）, thickness of root base （ 3 cm）, root volume, fresh weight of axial root, dry weight of axial root, fresh weight of lateral root, dry weight of lateral root, number nodules of lateral root and number nodules of axial root were analyzed. We evaluated number of genes controlling the characters and estimated relation analysis in the characters, and studied genes interaction of controlling the root characters based on their skewness and kourtosis values. The results revealed there was highly significant or significant difference in 6 characters, in their parents. But regardless of marked difference or no in their parents, all of traits in RIL population showed continuous variation and large aggressive segregation. And coefficient of variation was small in the traits of length of axial root and thickness of root base （ 1 cm） （ CV = 11.27% and 11.22%, respectively）. Peanut root characters were all quantitative traits genetically controlled by polygenes. For instance there were about 10 genes controlling number nodules of lateral root and fresh weight of lateral root and dry weight of lateral root. But there were about 5 - 7 gene in others characters, especially 5 genes in number of lateral root. Except for dry weight of lateral root （ hn = 0. 569） and number nodules of lateral root （ hn = 0. 545） and number of lateral root （ hn = 0. 542）, the heritability of the others was lower in RIL populations. At the same time, gene interaction was observed in part of characters, transgressive segregation gene interaction observed in polygenes controlling length of axial root and thickness of root base （ 1 cm）, significant complementary gene interaction detected in nodule number of lateral root and dry weight of lateral root and nodule number of lateral root; but not detected out or not significant in the others. There was significant correlation between dry weight of axial root, dry weight of lateral root and thickness of root base （ 1 cm）, thickness of root base （ 3 cm ） and root volume. Root volume was significantly correlated with thickness of root base （3 cm）. There was no correspondence in relation to root volume between fresh weight of axial fresh and weight of lateral root.