正交设计在苜蓿青贮添加剂试验中的应用研究

Studies on the application of orthogonal design in additive experiment of Medicago sativa silage

初花期收获的苜蓿经过不同时间的晾晒(水分含量分别是80.3%、71.2%、62.5%、40.3%),添加不同含量的乳酸菌(0、106、107、108cfu/g)、纤维素酶(0、0.025、0.05、0.1 g/kg)和葡萄糖(0、10、15、20 g/kg)进行苜蓿青贮的4因子4水平的正交试验。结果表明,凋萎苜蓿组(水分含量为71.2%)青贮时,在4个水分组中具有最好的青贮质量,即降低青贮料中的NH3-N含量和生成更多的乳酸。4个因子对苜蓿青贮品质的影响顺序依次是葡萄糖添加量>苜蓿含水量>纤维素酶添加量>乳酸菌添加量。正交试验所得的最佳组合是:苜蓿水分含量为71.2%,乳酸菌的添加量为106cfu/g,纤维素酶的添加量为0.1 g/kg,葡萄糖的添加量为20 g/kg。

Orthogonal test of 4 factors and 4 levels was included in this experiment,they were wilting time （water content was 80. 3% ,71.2%,62.5%and 40.3 % respectively）, adding dose of lactic acid bacteria（0 cfu/g, 10^6 cfu/g, 10^7 cfu/g, 10^8 cfu/g）,cellulose （0 g/kg,0. 025 g/kg,0.05 g/kg,0. 1 g/kg）and glucose（0 g/kg, 10 g/kg,5 g/kg, 20 g/kg）respectively. The results demonstrated that among four water combinations, ensiling quality of wilted Medicago sativa （water content was 71.2%） was the best,because it reduced the content of NH3-N in silage and produced much lactic acid bacteria. The effect degree of 4 factors on Medicago sativasilage from big to small was glucose,water content,cellulose and lactic acid bacteria respectively. In orthogonal test, the best combination was gained when water content of Medicago sativa ,adding dose of lactic acid bacteria,cellulose and glucose was 71.2%, 106 cfu/g,0.1 g/kg and 20 g/kg respectively.