重庆地区15种饲料用桑树不同生长期粗蛋白含量的动态分析

旨在研究重庆地区15种饲料用桑树在不同生长周期粗蛋白含量的动态变化规律。以2年生15种饲料用桑树为研究对象,分别对其发芽期、旺盛生长期和缓慢生长期3个不同生长期的粗蛋白含量进行测定与分析。结果表明：在发芽期,桑树叶粗蛋白含量最高的品种为充桑（22.41%）,含量最低的品种为延边桑27~#（14.45%）;在旺盛生长期,桑树叶粗蛋白含量最高的品种是葵桑（20.82%）,含量最低的品种是延边桑27~#（13.81%）;在缓慢生长期,保持有较高粗蛋白含量的品种是充桑（19.95%）和云南10号（19.09%）,而粗蛋白含量较低的是嘉陵16号（13.44%）;在桑树的整个生长期,大部分品种的粗蛋白含量随时间推移呈不同程度的下降趋势,其中葵桑、双头荷叶白以及嘉陵16号的下降趋势最为明显,而云南10号、大中华、新一之濑、充桑以及丰台等品种在缓慢生长期的粗蛋白含量较旺盛生长期有不同程度的升高。研究结果为了解饲用桑树叶片在不同生长阶段的营养价值变化规律以及实现桑树叶科学、合理的饲料化利用提供了试验依据。

Dynamic Characterization of Crude Protein Content in 15 Varieties of Mulberry Leaves for Feed Use in Different Growth Periods

This experiment was conducted to study the dynamic variation rule of crude protein content of 15 mulberry varieties for feed use in different growth periods in Chongqing Region. A total of 15 different varieties of two-year-old mulberry for feed use were used as experimental materials, and the crude protein content in their leaves in three different growth stages, including germination period, vigorous growth period and slow growth period were determined, respectively. The results showed that in the germination period, the highest and lowest crude protein content in leaves were observed in the varieties of Chongsang（22.41%）and Yanbiansang 27~#（14.45%）, respectively; in the vigorous growth period, the varieties of Kuisang（20.82%） and Yanbiansang27~#（13.81%） had the highest and lowest crude protein content in leaves, respectively; in the slow growth period, the varieties of Chongsang（19.95%） and Yunnan No.10（19.09%） maintained a higher level of crude protein in leaves, while the lower crude protein content in leaves were found in the variety of Jialing No.16（13.44%）; during the whole growth period, for most of the mulberry varieties, the crude protein content in leaves exhibited an decreasing trend in different degrees, and the most obvious decreasing trend was observed in the varieties of Kuisang, Shuangtouheyebai and Jialing No.16; nevertheless, for the varieties of Yunnan No.10, Dazhonghua, Xinyizhilai, Chongsang and Fengtai, the crude protein content in leaves expressed an elevating tendency from vigorous growth period to slow growth period. Our results provide experimental basis for understanding the dynamic variation rule of nutritional value of mulberry leaves for feed use in different growth periods and implementing scientific and rational feed utilization of mulberry.