Abstract:

The aim of this study was to observe the change trends of lactic acid bacteria (LAB) on plants from harvest to 24 h placing. The number and species of LAB of sweet corn (Zea mays L.) and king grass Reyan No.4 (Pennisetum purpereum×P. typhoideum‘Reyan No.4’) were tested from mowing, chopping, placing 8 h to 24 h. The results showed that the amount of LAB significantly increased from harvest (4.25 lg cfu·g^-1 FM) to chopped (5.69 lg cfu·g^-1 FM) stages (P <0.05), mainly the increase of Lactococcus lactic, Leuconostoc citreum and Weissella confuse. With the increase of placing time, species of LAB varied significantly, and their changes were also different on different plants. For example, Leuconostoc citreum was isolated after sweet corn stalk was chopped, Leu pseudomesenteroides was isolated after placing for 24 h, but Lactobacillus brevis was disappeared after king grass was chopped.

Key words: Harvest, Ensiling, Lactic acid bacteria, Dynamic change

摘要：

为调查收割至青贮装填前乳酸菌的动态变化，本研究以甜玉米（Zea mays L.）和热研四号（Pennisetum purpureum×P.americanum'Reyan No.4'）王草为材料，检测从刈割、切短、放置8 h和放置24 h四个阶段乳酸菌的动态变化。研究结果表明：从未切短（4.25 lg cfu·g^-1 FM）到切短（5.69 lg cfu·g^-1 FM）阶段乳酸菌的数量显著增加（P<0.05），主要是乳酸乳球菌（Lactococcus lactic）、柠檬明串珠菌（Leuconostoc citreum）和融合魏斯氏菌（Weissella confuse）。随着放置时间的延长，乳酸菌种类变化随植物品种而异，甜玉米切短后发现柠檬明串珠菌，放置24 h后发现假肠膜明串珠菌（Leuconostoc pseudomesenteroides），而热研四号王草切短后菌株短乳杆菌（Lactobacillus brevis）消失。

关键词: 刈割, 青贮填装, 乳酸菌, 动态变化