Powder formulations of two strains of Bacillus subtilis for control of rape seed damping-off caused by Rhizoctonia solani.
Talc-based formulations of Bacillus subtilis strains B1 and B2 were tested as seed and soil treatments separately for their ability to control Rhizoctonia solani, the causal agent of rape seed damping-off, in greenhouse and field trials. In general, the formulated bacteria was more effective to suppress the disease than the suspension of bacterial cells in carboxymethylcellulose solution (1%, w/v), in both greenhouse and field trials. The formulations of strain B1 as soil treatment and strain B2 as seed treatment in greenhouse, and the formulations of strain B2 as seed and soil treatments in field trials had the greatest effect on reducing the rape seed damping-off (66.7%, 73.3%, 41.3%, and 42.4%, respectively). The formulations of strain B1 as soil treatment and strain B2 as seed treatment were the most effective treatments to increase the root dry weights in the infected soil in greenhouse. The formulation of strain B2 as soil treatment had the greatest effect on enhancement of the fresh weight of roots and stem fresh and dry weights. The formulations of strains B1 and B2 stored at 4 degrees C exhibited better shelf life and efficacy in vitro than their counterparts stored at 25 degrees C. Long-term stability of the formulation of strain B1 was found to be better.
Sharifi-Tehrani
A
A
Department of Plant Protection, University of Tehran, Karaj, Iran.
Ahmadzadeh
M
M
Farzaneh
M
M
Sarani
S
S
D001412:Bacillus subtilis / Q000502:physiology*; D029741:Brassica rapa / Q000382:microbiology*; D010572:Pest Control, Biological / Q000379:methods*; D018517:Plant Roots / Q000254:growth & development / Q000382:microbiology; D012232:Rhizoctonia / Q000254:growth & development*; D012988:Soil Microbiology; D013997:Time Factors