关键词: 甜高粱, 糖锤度, 农艺性状, 产量, 相关性, 生育时期

Abstract:  The aim is to explore the correlation between the sugar brix of stalk and agronomic traits， biological yield in different growth stages of sweet sorghum，and to explicit the determinants for the sugar brix formation of sweet sorghum，so as to provide reference basis for rational evaluation and utilization of existing germplasm resources and breeding varieties.The correlation between the sugar brix of stalk in the anthesis stage，grain-filling stage，early endosperm maturation，late endosperm maturation，dough stage and the plant height，rate of juice，effective sugar content and biological yield was studied using the sweet sorghum materials of sw-1，sw-2，sw-3 and sw-4.The results showed that the correlation between the sugar brix of stalk and plant height was not obvious at different growth stages.There was a significant negative correlation between the rate of juice and sugar brix in grain-filling stage.At the grain-filling stage，the sugar brix of stalk showed a significant negative correlation with effective sugar content，and an extremely significant negative correlation with biological yield.There was a positive correlation of sugar brix between  anthesis stage and grain-filling stage，while there was a negative correlation of sugar brix between anthesis stage and early endosperm maturation，late endosperm and dough stage．There was a negative correlation of sugar brix between grain-filling stage and early endosperm maturation，late endosperm maturation，while there was a positive correlation of sugar brix between grain-filling stage and dough stage．Furthermore，there was a positive correlation of sugar brix between early endosperm maturation and late endosperm maturation，dough stage．The sugar brix of late endosperm maturation was positively correlated with that of dough stage.The path analysis of sugar brix of stalk between dough stage and anthesis stage，grain-filling stage，early endosperm maturation and late endosperm maturation showed that the sugar brix of stalk in the early endosperm maturation had the greatest influence on the sugar brix of stalk during the dough stage．And the path coefficient was 1.418 3.By combining the above analysis，it is concluded that when selecting high-yield，high-brix materials in sweet sorghum breeding，the parents with high sugar brix during the early endosperm maturation should be selected．

Key words:  Sweet sorghum, Sugar brix, Agronomic traits, Yield, Correlation, Growth stage