药用植物麦冬土壤中拮抗放线菌的分离和筛选

采用平板稀释分离法从麦冬植被土壤中分离得到放线菌52株,以大肠杆菌、枯草芽孢杆菌、巨大芽孢杆菌为指示细菌,采用平板涂抹法筛选出17株有拮抗作用的放线菌,其中抑菌效果较好的放线菌是F13、F25、F50号菌株,其抑菌圈直径在15～20 mm之间,占分离得到放线菌总数的5.77％,F13号菌株的抑菌作用最强,抑菌圈直径达20 mm;采用平板对峙法进一步测定了F13、F25和F50菌株对棉花黄萎菌、番茄早疫菌和玉米串珠镰刀菌的菌丝生长抑制率,F13对黄萎菌的抑菌效果较强,抑菌率为56.7％,F25对串珠镰刀菌的抑菌效果较强,抑菌率为41.2％.

Isolation and screening of Antagonistic actinomycetes from soil of medicinal plant Ophiopogon japonicus

Fifty -two types of actinomycetes were separated from soil samples collected from medicinal plant Ophiopogon japonicus, and 17 antagonistic actinomycetes were screened from 52 actinomycetes by plate smearing test using Escherichia coli, Bacillus subtilis and Bacillus megaterium as indicator bacteria. 3 actinomycetes strains F13, F25 and F50 had better inhibition effects accounting for 5.77% of the total number and with an inhibition zone of 15-20mm. And the inhibition effect of strain F13 was the best one with an inhibition zone diameter of 20 mm. The mycelial growth inhibition rates of F13 F25 and F50 to Verticillium dahliae from cotton, Alternaria Solani from tomato, Fusarium moniliform from maize were tested by plate confrontation method, F13 could inhibit V. dahliae intensively with the inhibition rate of 56.7%, and F25 could inhibit F. moniliform intensively with the inhibition rate of 41.2%.