关键词: 狗尾草, 狗尾草, 黑麦草, 白三叶, 紫茎泽兰, 不同肥力, 控制效果, 竞争力

Abstract: In this paper, the Lactobacillus casei of bile salt hydrolase screened from Tibetan Kefir were used to study environment factors of increasing enzyme vires. For four factors to affect synthesize of bile salt hydrolase, fermentation conditions of high yield bile salt hydrolase were determined by four factors and three levels orthogonal experiments [L9(3)4]. As follows: glucose 2%, Soya-peptone 2%,fermentation temperature 37℃, amount of inoculation 2%.Under optimization conditions，the vires of bile salt hydrolase was enhanced to 7.4 times.