57NG208与南涧果蔗正反交后代的遗传变异分析

Heredity and variation analysis onhybrid generation from reciprocal crosses between Saccharum robustum of 57NG208 and fruit sugarcane of Nanjian

通过对甘蔗大茎野生种57NG208和南涧果蔗正交、反交后代132个真杂种后代的聚类分析及对其株高、茎径、丛有效茎数、锤度和单茎重的分析,研究其后代群体的遗传变异。结果表明：1）57NG208与南涧果蔗正交组合66个后代的Jaccard遗传相似性系数为0.227-0.955,平均为0.618;反交组合的为0.206-0.941,平均为0.593。2）正交、反交后代的变异系数中,丛有效茎数的变异系数最大（大于50%）,其次为单茎重的变异系数（大于33%）,说明丛有效茎数和单茎重的离散度较大;茎径的变异系数为14%-16%;锤度和株高的变异系数均在11%以下,说明株高和锤度的离散度最小。3）正交、反交后代的遗传传递力中,遗传传递力大于100%的有丛有效茎数和锤度,株高和茎径的约为80%,单茎重的小于70%。4）正交、反交后代的性状表现超过双亲的有锤度和丛有效茎数;除丛有效茎数外,正交组合的株高、茎径、丛有效茎数和锤度4个性状的平均值均高于反交组合。

A total of 132 true hybrids from reciprocal cross between Saccharum. robustum 57NG208 and fruit sugarcane of Nanjian were used to study the genetic variation of their descendants by means of SSR markers and parameters of plant height（PH）, stalk diameter（SD）, millable stalks per stool（MSS）, Brix and single stalk weight（SSW）. The result indicated that the genetic similarity（GS） among 66 hybrids descendants directly crossed from 57NG208 and Nanjian ranged from 0.227 to 0.955, with average of 0.618, while, the back cross ranged from 0.206 to 0.995, with average of 0.593; the coefficient of variance（CV） from MSS was the highest（over 50%）, followed by SSW（over 33%）, the next was SD（14%–16%）, and the lowest was Brix and PH（below 11%）; the genetic transmitting ability from MSS and Brix were over 100%, followed by PH and SD which were about 80%, it was lowest of SSW which was below 70% for; Two traits Brix and MSS for hybrids descendants were higher than those of parents, and the values of 4 traits like PH, SD, Brix and SSW which were from descendants crossed by 57NG208 and Nanjian and were higher than those of back cross generation.