两种生防新药剂对马铃薯晚疫病防效及产量的影响.

Phytophthora infestans is the pathogenic fungus causing potato late blight. The quality of chemical control agents is uneven and new biological control agents are urgently required. Therefore, in this study, Dingxi City, Gansu Province, where potato late blight incidence is high, was selected as the test place, and two new biocontrol agents and three conventional chemical agents were introduced to carry out a comparison test of indoor bacteriological inhibition and field control efficiency, to explore the effects of new biocontrol agents on potato late blight control efficiency and yield. Biocontrol agent, 10.5 billion CFU/g Polymyxa · Subtilis WP, had a bacteriostatic effect of 96.7% indoors and 76.5% in the field and increased the yield by 7.70% compared with the control treatment. The bacteriostatic effect of 68% Mefenoxam·Mancozeb WP in the laboratory conditions was 98.3%, in the field 73.1%, and the yield was 7.51% higher than that of the control treatment. There was no significant difference between the two treatments except for control effect in the field. The indexes of the two treatments were significantly better than that of the biocontrol agent 1 billion CFU/g Bacillus marinus WP, and chemical treatments of 32.5% Benzoyl ·Azoxystrobin SC and 50% Metalaxyl · Propineb WP. In conclusion, the new biocontrol agent of 10.5 billion CFU/g Polymyxa·Subtilis WP could be used as the control agent to control potato late blight in Dingxi City. [ABSTRACT FROM AUTHOR]