Abstract: The change pattern of the vegetative growth and forage quality of Sorghum bicolor×S.sudanense was analyzed.Plant height,dry matter accumulation,HCN content,fresh/dry ratio,sugar content and crude protein were investigated and analyzed during different growth stages.Results showed that the change of plant height,dry matter accumulation and crude protein yield of Sorghum bicolor×S.sudanense was related to a logistic growth model under different growth stages,and the max value was in heading stage.With an extended growth period,the HCN content,crude protein content and the ratio of fresh/dry had a decreasing trend while the ratio of stem/leaf showed an increase;their regularity of changes fit the linear regression mode.The sugar content of Sorghum bicolor×S.sudanense complied to a quadratic curve regression mode with different growth days,presenting an initial drop followed by its rising trend.Data suggests that Sorghum bicolor×S.sudanens.should be harvested at its heading stage to produce better biomass and nutritive value.

Key words: Sorghum bicolor×S.sudanense, Nutritive growth, Forage quality, Regression

摘要： 为揭示高丹草(Sorghum bicolor×S.sudanense)在营养生长及饲用品质方面的变化规律,采用大田小区栽培法,以冀草1号、冀草2号高丹草为材料,测定并分析了不同生育天数内其株高、干物质积累量、氢氰酸含量、鲜干比、可溶性糖含量、茎叶比以及粗蛋白含量等性状指标。结果表明:高丹草的株高、干物质积累量以及粗蛋白产量的变化随生育天数的推进符合Logistic增长模型,均在抽穗期达到最大值;其氢氰酸含量、鲜干比及粗蛋白含量呈下降趋势,茎叶比呈增加趋势,符合一元线性回归模型;而可溶性糖含量变化符合二次曲线回归模型。回归分析得出,高丹草在抽穗期收割可同时获得较高的物质产量和营养价值。

关键词: 高丹草, 营养生长, 饲用品质, 回归分析