Abstract:

The organic-sulfur fumigant Dazomet could effectively reduce the population of bacteria , fungi and nematodes in soil . Bacillus subtilis G3^str as a biocontrol strain could multiply in soil fumigated by Da-zomet with addition of nutritional amendment . The enhanced population of G3^str in sterile soil was higher
than that in non-sterile soil . In the first six days after addition , the amount of lipopeptides and iturin were at a higher level in sterile soil than in non-sterile soil as well . Sclerotia formation by Rhizoctonia solani in soils was greatly inhibited in fumigated soil amended with G3^str compared with fumigated soil without G3^str . Pottrials indicated that Pythium aphanidermatum damping-off of eggplant was significantly reduced by addition of G3^str and was enhanced by fumigation. Combination of fumigation with biocontrol agents was suggested as an effective way for control of soil-borne plant diseases.