广西甘蔗区试品种生长前期对螟虫的抗性评价

【目的】明确广西各区试点的甘蔗螟虫为害情况及品种抗性,为品种合理布局和螟虫综合防控提供依据。【方法】2015年,在甘蔗生长前期对广西6个区试点的螟害发生情况进行实地调查。根据发生程度,利用枯心指数划分的抗性标准和聚类分析的方法对品种的田间抗性综合评价。【结果】各区试点螟害枯心率0~30.60%,枯心指数0~100.00,南宁试点的螟害发生率最高。参试品种中,未发现抗螟虫品种,中感(MS)品种6个,占50%;感虫(S)品种4个,占33%;高感(HS)品种2个,占17%。系统聚类分析结果与参试甘蔗品种的抗性表现一致。【结论】螟虫在不同区试点的发生程度差别明显,参试品种之间存在显著抗性差异,且新植蔗的螟害发生情况较宿根蔗重。

Genetic Determination and Selection of Sugarcane Families

Sugarcane family evaluation on 108 hybridized combinations generated during 2013-2014 was conducted by measuring the main traits of plant and ratoon crops. Stalk height, stalk diameter, stalk number per stool and brix were investigated in both plant cane and ratoon cane, while stalk 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 based on comprehensive index method. The results showed that the stalk height of both plant and ratoon, stalk diameter of both plant and ratoon, stalk number per stool of plant, brix of both plant and ratoon, stalk weight per stool and brix weight per stool were sig- nificantly different among the families. Stalk height, stalk diameter, stalk number per stool of plant crop showed higher level of broad-sense heritability, genetic variation coefficient and relative genetic advance than those in ratoon crop. But there were no significant differences in broad-sense heritability, genetic variation coefficient and relative genetic advance of brix between plant and ratoon crops. Analysis of phenotypic and genotypic correlation showed that stalk weight per stool was significantly correlated with brix weight per stool, Fifteen elite families including Zhanzhe 74-141× CP72-1210, Guitang 05-3081×Yuetang 91-976, Yunzhe 02-588×ROC22, Funong 39× Guitang 03-1229, Guitang 02-901×Guitang 03-2357, Guitang 05-2743×Guitang 03- 1229, Guitang 92-66×ROC22, Dezhe 93-88×ROC22, Guitang 05-3445×Guitang 03- 2309, Yuetang 00-319×CP72-1210, Guitang 03-3089×ROC22, Yuetang 91-976×CP84- 1198, Yuefu 90-95 ×CP72-1210, Yunzhe 99-601×Guitang 00-122, Yuetang 00-236× ROC22 were selected based on comprehensive index method, and stalk weight per stool and brix weight per stool showed greater genetic gain. The families selected based on comprehensive index were not completely the same as the families selected by brix weight per stool, the rank correlation coefficient of the families selected based on comprehensive index and brix weight per stool was 0.748 （P〈0.01）.