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）.

A Survey Report on Sugarcane Production in Guangxi Zhuang Autonomous Region in 2013

In order to fully understand sugarcane production in Guangxi in 2013,the sample survey combined with data collection and field survey was carried out in sugarcane production areas in Nanning,Hechi,Liuzhou,Chongzuo,Baise and Laibin from May 28 to June 36 in2013. It was found that the sugarcane growing area in Guangxi in 2013 declined compared with that in 2012; the rate of emergence remained the same as previous year,and as for the plant number of plant crop and ratoon crop per hectare,there was a decline of 4000 and 2000 seedlings respectively compared with the figure in 2012; borer damage rate declined on the whole while the incidence of sugarcane smut increased.Due to the growth in the cost of planting,the growers were less enthusiastic for management. According to the findings,the fertilization and sugarcane field management should be accelerated; borer prevention work was also required,so as to reduce borer damage and dieback rate;the planting structure of varieties had to be adjusted and the cultivated area of " Guitang" as a fine sugarcane variety should also be enlarged;meanwhile other active measures needed to be taken to prevent and control the outburst of pest attack in local areas.