Studies Of Screen And Characters Of Antagonistic Bacteria Against Fusarium Oxysporum Schl.F.Sp. Cubense

Fusarium oxysporum f.sp. Cubense race 4 has spreaded with violence and made deeply damage in banana-growing region for many years.The colonization ability of bio-control microbe in banana is decided to the sources of them.Meantime there are different effect to control the Fusarium Oxysporum resultant of FOC4.From root site of banana cultivation seedlings.2482 strains of root microbe were separated and pured.18 strains of them have obvious antagonist effects to FOC4. It's proved by PDA plating confrontation that all of 18 strains have the stable antagonist role.16 strains of them were fell under bacillus by the analysis of the biological characterstics and 16SrDNA sequerce.2 strains which have best antagonist effects(No.0165 and 1150) was researched furtherly. Colonization ability of 0165-rif and 1150-rif was detectied, and the strains could stay in the banana roots for more than 40 days.By using carbendazim as Positive contrast, the effect of 0165's fermentation liquor and 1150's fermentation liquor diluted to 60 times was similar to that of carbendazim diluted to 700 times.The antagonist effects of 0165 and 1150 were not nutrition competition. The protain of 0165's fermentation liquor had antagonist effects on FOC4, and the inhibitory rate was 67% of that of the original, lasting about 3 days.