菌酶添加对喀斯特地区全株青贮玉米发酵品质和有氧稳定性的影响

Effects of Bacterium and Enzyme Addition on The Fermentation Quality and Aerobic Stability of Whole Plant Maize Silage in Karst Areas

试验旨在研究添加菌酶对喀斯特地区全株青贮玉米发酵品质和有氧稳定性的影响,为新型青贮菌剂的应用提供参考。以真空袋法青贮全株玉米,设5个试验组和1个对照组,分别为添加等量纯化水(对照组)、植物乳杆菌(试验A组)、纤维素分解菌(试验B组)、纤维素酶(试验C组)、植物乳杆菌+纤维素分解菌(试验AB组)、植物乳杆菌+纤维素酶(试验AC组)。其中植物乳杆菌添加1×10^(5) CFU/g;纤维素分解菌为黑曲霉∶枯草芽孢杆菌=2∶1,添加量为3.0×10^(5)、1.5×10^(5) CFU/g,纤维素酶按0.3%添加。发酵60 d后同时采样并测定全株玉米的发酵特性、乳酸菌数量、营养成分、有氧稳定性指标。结果表明:试验组均有微弱香味,对照组则气味较平淡,综合评分均到达一级;试验组pH均低于4.2,达到优质青贮料标准,C、AC组pH显著低于A、B、AB组(P<0.05);A、B、C组乳酸(LA)含量显著高于对照组(P<0.05);试验组乙酸(AA)含量高于对照组,但差异不显著(P>0.05),丙酸(PA)和丁酸(BA)均未检测出;A、B、C、AB组氨态氮(NH3-N)含量显著高于对照组(P<0.05);试验组有氧稳定性(AS)时间均显著高于对照组(P<0.05);AB组粗蛋白(CP)显著高于其他试验组(P<0.05);试验组干物质(DM)含量显著高于对照组(P<0.05);B、AB组粗灰分(Ash)含量显著低于对照组(P<0.05)。采用隶属函数法综合各项指标进行评价,各组优劣排序为AC组>C组>AB组>B组>A组>对照组。说明AC、AB组可有效改善全株青贮玉米的青贮品质,提高有氧稳定性,以AC组效果最好;因此,纤维素分解菌可在一定程度上替代纤维素酶用于全株青贮玉米发酵。

The aim of this experiment was to study the effect of enzyme addition on the fermentation quality and aerobic stability of whole plant maize silage in Karst areas,and to provide a reference for the application of new silage agents.The different additives bacteria were added to the whole plant silage maize and sealed in a vacuum bag.Five test groups and one control group were set up.The control had add an equal amount of distilled water.The A contained Lactobacillus plantarum;the B contained cellulose decomposing bacteria,the C contained Cellulase,the AB contained Lactobacillus plantarum and cellulose decomposing bacteria;the AC contained Lactobacillus plantarum and Cellulase,Among them,Lactobacillus plantarum added 1×10^(5) CFU/g,cellulose decomposing bacteria are Aspergillus niger∶Bacillus subtilis=2∶1,with added 3.0×10^(5),1.5×10^(5) CFU/g respectively,Cellulase added at 0.3%.Fermentation characteristics,lactic acid bacteria,nutrient composition,aerobic stability and other indexes were determined by sampling after 60 days of fermentation.The results showed,that the odour of each treatment group could be obviously smelled faintly,while the control group had a bland odour,and the overall score reached grade 1;pH of each test group was for 4.2,which reached the standard of high quality silage,and the pH of C and AC groups was significantly lower than that of A,B and AB groups(P<0.05).LA content of A,B and C treatments was significantly higher than that of control group(P<0.05).The difference in acetic acid was not significant(P>0.05),the propionic acid and butyric acid wasn't detectied.NH3-N was significantly higher in A,B,C and AB treatments than in control group(P<0.05).Aerobic stability time was significantly higher in all treatments than in control group(P<0.05).CP was significantly higher in AB treatment than in other treatments(P<0.05);DM was significantly higher in all treatments than in control group(P<0.05).B,AB treatment ash was significantly lower than control group(P<0.05).The difference in acetic acid was not significant(P>0.05),the propionic acid and butyric acid wasn't detectied.The comprehensive values of the 5 test groups and one control group,as calculated from the 14 indexes by a membership function analysis,were as follows:AC group>C group>AB group>B group>A group>control group.The results show that the AC and AB are effective in improving silage quality and aerobic stability of whole plant silage maize.The best results were obtained with the AC;cellulose decomposing bacteria can replace Cellulase to a certain extent in the fermentation of whole maize silage.