کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6373103 | 1624297 | 2016 | 10 صفحه PDF | دانلود رایگان |
- Four biocontrol formulations were tested against Rhizoctonia disease of potato.
- All formulations reduced stem canker (37-75%).
- B. subtilis, Bu. ambifaria, and T. virens treatments reduced black scurf (11-20%).
- B. subtilis, T. virens, and chem./biological treatments increased tuber yield 11-15%.
- Only T. virens was still detected in soil the following year (1 year later).
Four commercial biocontrol formulations (Bacillus subtilis GB03, Burkholderia ambifaria type Wisconsin isolate J82, Trichoderma virens Gl-21, and Trichoderma harzianum strain T-22), a chemical seed treatment (thiophanate-methyl, mancozeb, and cymoxanil mixture, TMC), and a combination chemical/biological treatment, were compared with no-pathogen and pathogen-treated controls, and monitored in two field seasons in Maine for their effects on the development of Rhizoctonia disease of potato and soil microbial community characteristics. All treatments reduced the incidence and severity of stem canker (37-75% reduction) relative to the pathogen control over both years, with the best control provided by B. subtilis and the combination chemical/biological treatment (TMC/Bamb). Both bacterial treatments (B. subtilis and Bu. ambifaria) reduced severity of black scurf in both years, and T. virens reduced scurf in one year, with reductions of 11-20% relative to the pathogen control. Over both years, the B. subtilis, T. virens, and TMC/Bamb treatments increased total and marketable yield, and Bu. ambifaria increased marketable yield, by 11-15% relative to the pathogen control. Substantial populations of the added fungal agents, but not the bacteria, were detected in bulk soil at the end of the growing season. Biocontrol treatments also significantly (P < 0.05) affected soil microbial community characteristics, as assessed by single carbon source substrate utilization (SU) and whole soil fatty acid methyl ester (FAME) profiles. Bacterial biocontrol treatments generally resulted in higher microbial activity and substrate utilization. Some effects on soil microbial communities were also observed the following spring (1 yr after application). This research indicates that biocontrol treatments can assist in the control of Rhizoctonia disease of potato, persist in soil to some degree, and have significant effects on soil microbial communities long after application.
Journal: Crop Protection - Volume 90, December 2016, Pages 96-105