棉 花 学 报    Cotton Science    2007，19(3)：210-213

Screening of Antagonistic Bacteria Against Cotton Seedling Diseases and Measure of Controlling
DONG Hong-qiang ^1，2，MU Wei¹，LIU Feng¹，CHEN Zhaoliang¹，LIU Yuequn¹
(1.College of Plant Protection，Shandong Agricultural University，Shandong 271018，China；
2.Institute of plant Science and Technology，Tarim University，Xinjiang 843300，China)

Abstract：Having collected 12 samples of soil from cotton planting regions in Dezhou，Shandong Province ，and using confronted culture method in dilute microbe，we had separated 11 strains of antagonistic bacteria on Rhizoctonia solani. Their antagonistic ability against pathogens of cotton seedling diseases including Rhizoctonia solani，Alternaria macrospora，Fusarium moniliforme and Fusarium oxysporum showed much difference in vitro laboratory experiment. We discovered the strain D24 had much strong and stable antagonistic capacity. Inhibitive effect of the fermentative extracts of the strain D24 against growth of four pathogens of cotton seedling diseases were respectively 84.6%，82.7%，81.2% ，72.8%. Using the fermentative extracts of the strain D24 to treat the seedling of cotton，it had no effect with germination of cotton. The strain D24 was dealt with cotton seedling in the spot where we had brought some soil from Dezhou. The results showed that control of D24 treatment on cotton seedling diseases reached 50.1% as compared with the control. The morphology，culture characteristics and physiological properties of strain D24 extremely similar to physiological properties of Bacillus Cohn ，so the strain D24 is tentatively confirmed as Bacillus Cohn.
Key words：cotton；seeding；diseases；antagonistic bacteria；control effect.   [Full Text，2799KB]