添加植物乳杆菌对桑枝叶与玉米秸秆混合青贮发酵品质的影响

Effects of Lactobacillus plantarum additives on fermentation quality about mixed silages of branch and leaf of mulberry and maize straw

试验旨在研究添加植物乳杆菌对桑枝叶与玉米秸秆混合青贮发酵品质的影响。将桑枝叶与玉米秸秆以1.1(鲜重)混合青贮,并分别添加0%、2%、4%、6%和8%植物乳杆菌制剂(占青贮原料鲜重比例),共5个处理,每个处理3个重复,使用聚乙烯袋真空包装,室温贮藏60 d后开启取样分析。结果表明:(1)添加剂组干物质含量均低于对照组,干物质回收率和可溶性碳水化合物含量均高于对照组;(2)随着植物乳杆菌制剂添加量的增加pH值不断下降,LAP 6%组和LAP 8%组的pH值均显著低于对照组(P<0.05),分别为4.15和4.01;各试验组乳酸含量均显著高于对照组(P<0.05),其中LAP 6%组的乳酸含量最高;乙酸和丁酸含量各组间差异不显著(P>0.05);(3)LAP 2%组发酵品质良好(42分,1级),其他各组发酵品质优等(45~48分,1级)。综上所述,桑枝叶与玉米秸秆以1.1(鲜重)混贮,LAP 6%组发酵品质最佳。

This experiment was to study the effect of adding Laetobacillus pIantarum on the dynamics of fermentation characteristics of mixed silages of branch and leaf of mulberry and maize straw during ensiling. Mixture of branch and leaf of mulberry and maize straw（1 ： 1, fresh weight） was ensiled, and each mixed silages was supplied with 0%, 2%, 4%, 6% and 8% Lactobaeillus plantarum additives （proportion of fresh weight of silage materials）, the experiment was divided into 5 groups and each processing repeated three times. The silages were packaged by vacuum packager in polyethylene bags, stored at room temperature for 60 days, and then to open the bags and analyze. The results showed as follows： The dry matter content of the additive group was all lower than that of the control group, and the dry matter recovery and soluble carbohydrate content were all higher than those of the control group. With the increase of Lactobacillus plantarum dosage, the pH value decreased constantly. The pH values in LAP 6% and LAP 8% groups were significantly lower than those in the control group （P〈0.05）, which were 4.15 and 4.01, respectively; The content of lactic acid in each test group was significantly higherthan that of the control content of lactic acid in group （P〈0.05）, and the LAP 6% group was the highest; There were no significant difference in the content of acetic acid and butyric acid （P〉 0.05）. The fermentation quality of the LAP 2% group was good （score 42, grade 1）, and the other groups were excellent in fermentation quality （score 45-48 points, grade 1）. A combination of all index, mixture of branch and leaf of mulberry and maize straw（1 ： 1, fresh weight） were ensiled, the fermentation quality of the LAP 6% group was the best.