甘蔗家系的遗传测定与选择

以2013—2014年配制的108个甘蔗常用组合为研究对象,进行了1新1宿家系试验。通过测定家系新植和宿根的株高、茎径、丛有效茎数、锤度及新植丛重、新植锤重性状,分析各性状的遗传变异及估计性状的遗传参数,并进行了家系的综合指数选择。结果表明:除宿根丛有效茎数之外,其他所有性状在家系间均存在极显著差异;新植蔗的株高、茎径、丛有效茎数的广义遗传力、遗传变异系数和相对遗传进度均高于宿根蔗的。新植蔗和宿根蔗的锤度的广义遗传力、遗传变异系数和相对遗传进度的差异无统计学意义;在新植家系的性状相关分析中,只有锤重与丛重之间,表型和遗传相关达到了极显著水平;通过综合指数选择,选出了湛蔗74–141×CP72–1210、桂糖05–3084×粤糖91–976、云蔗02–588×ROC22、福农39号×桂糖03–1229、桂糖02–901×桂糖03–2357、桂糖05–2743×桂糖03–1229、桂糖92–66×ROC22、德蔗93–88×ROC22、桂糖05–3445×桂糖03–2309、粤糖00–319×CP72–1210、桂糖03–3089×ROC22、粤糖91–976×CP84–1198、粤辐90–95×CP72–1210、云蔗99–601×桂糖00–122、粤糖00–236×ROC22共15个优良家系,入选家系的丛重和锤重的遗传增益较大;综合指数选择与以锤重单性状选择的结果不完全相同,秩次相关系数为0.748,达极显著水平。

Genetic determination and selection of sugarcane families

Sugarcane family evaluation with 108 of 2013–2014 hybridized combinations was conducted for one plant crop and one ratoon crop. Stalk height, stalk diameter, stalk number per stool and brix were investigated in both plant cane and ratoon cane, while weight per stool and brix weight per stool were measured only in plant cane. Genetic variation and genetic parameters of all traits were analyzed, and the families were evaluated by comprehensive index method. The results showed that stalk height in plant and ratoon, stalk diameter in plant and ratoon, stalk number per stool in plant, brix in plant and ratoon, weight per stool and brix weight per stool were significantly different among the families. Stalk height, stalk diameter, stalk number per stool of plant crop performed higher level of broad-sense heritability, genetic variation coefficient and relative genetic than those in ratoon crop. But there were no significantly difference in broad-sense heritability, genetic variation coefficient and relative genetic of brix between plant crop and ratoon crop. Analysis of phenotypic and genotypic correlation showed that weight per stool was significantly correlated with brix weight per stool. Fifteen elite families including Zhanzhe74–141×CP72–1210, Guitang05–3081× Yuetang91– 976, Yunzhe02–588×ROC22, Funong39×Guitang03–1229, Guitang02–901×Guitang03–2357, Guitang05–2743× Guitang03– 1229, Guitang92–66×ROC22, Dezhe93–88×ROC22, Guitang05–3445×Guitang03–2309, Yuetang00–319× CP72–1210, Guitang03–3089×ROC22, Yuetang91–976×CP84–1198, Yuefu90–95×CP72–1210, Yunzhe99–601×Guitang00–122, Yuetang00–236×ROC22 were selected based on comprehensive index method, and weight per stool and brix weight per stool showed greater genetic gain. The families selected by comprehensive index selection were not completely the same as the families selected by brix weight per stool, the rank correlation coefficient of thefamilies selected from comprehensive index selection and brix weight per stool selection was 0.748 (P<0.01).