Dynamic analysis of contents of crude protein and amino acids in 6 kinds of forages in different growth periods | 黄河滩区6种牧草不同生育期粗蛋白和氨基酸含量的动态分析

chinois. 研究黄河滩区6种牧草不同生育期粗蛋白（CP）和氨基酸含量的动态变化规律。以黄河滩区2种禾本科牧草（多年生黑麦草和紫羊茅）、2种豆科牧草（紫花苜蓿和白三叶）、1种紫草科牧草（聚合草）和1种菊科牧草（串叶松香草）为研究对象，分别对其分蘖期、拔节期、开花期和成熟期等4个不同生育期的粗蛋白和氨基酸含量进行测定与分析。6种牧草总氨基酸（TAA）含量总体上随生育期的发展呈下降趋势，其中2种禾本科牧草几乎呈直线下降，而其他4种牧草TAA含量呈现“高―低―高―低”的双峰变化趋势，且2种豆科牧草TAA最高，2种禾本科牧草的TAA最低；2种禾本科牧草的TAA/CP随生育期的发展呈“高―低―高”的变化趋势，高峰值出现在分蘖期，其他4种牧草的TAA/CP高峰值出现在开花期。2种豆科牧草的总必需氨基酸/非必需氨基酸呈“低―高―低”的单峰变化趋势；其他4种牧草呈“高―低―高―低”的双峰变化趋势，高峰值出现在开花期。综合考虑TAA、赖氨酸（Lys）以及TAA/CP和产量认为，苜蓿、白三叶、多年生黑麦草、紫羊茅和串叶松香草的最佳收割期为开花期，而聚合草为成熟期。

anglais. The research studied the dynamic pattern of amino acids in 6 kinds of forages in different growth periods in Yellow River beach regions. 6 kinds of forages (Alfalfa, White clover, Ryegrass, Red fescue, Cup plont, Common comfrey) were selected to determine and analyze the contents of crude protein and amino acids in 4 different growth periods in Yellow River beach regions. The contents of amino acid reduced with the growth of 6 kinds of forages as a whole, and the amino acids contents of 2 kinds of gramineous forages almost linearly decreased, the others emerged two-peak (high-low-high-low) dynamic pattern, and the TAA of 2 kinds of leguminous forages were the highest; the TAA of 2 kinds of gramineous forages were the lowest; the TAA/CP of 2 kinds of gramineous forages were single-peak (high-low-high ) dynamic pattern; the peak value appeared in tillering stage, the others were in flowering stage. The TEAA /NEAA of 2 kinds of leguminous forages showed single-peak (low-high-low) dynamic pattern, the others were two-peak (high-low-high-low) dynamic pattern and the peak value reached in blossoming stage. Analyzing synthetically the above index and yield, the author considered the optimal harvesting time for Alfalfa, White clover, Ryegrass, Red fescue and cup plont was the flowering stage, however the optimal reaping stage of Common comfrey was the maturing stage.