Field efficacy of nonpathogenic Streptomyces species against potato common scab
Article first published online: 31 OCT 2013
© 2013 The Society for Applied Microbiology This article has been contributed to by US Government employees and their work is in the public domain in the USA
Journal of Applied Microbiology
Volume 116, Issue 1, pages 123–133, January 2014
How to Cite
Wanner, L.A., Kirk, W.W. and Qu, X.S. (2014), Field efficacy of nonpathogenic Streptomyces species against potato common scab. Journal of Applied Microbiology, 116: 123–133. doi: 10.1111/jam.12336
- Issue published online: 16 DEC 2013
- Article first published online: 31 OCT 2013
- Accepted manuscript online: 27 AUG 2013 02:18AM EST
- Manuscript Accepted: 22 AUG 2013
- Manuscript Revised: 9 AUG 2013
- Manuscript Received: 21 MAY 2013
- USDA-State Cooperative Potato
- USDA-ARS. Grant Number: 1275-21220-251-0OD
- biological control;
- common scab;
- disease suppression;
- nonpathogenic Streptomyces spp.;
- Streptomyces scabies
The primary objective of these experiments was to reduce pathogenicity and virulence of endemic soil pathogenic Streptomyces strains that cause potato common scab (CS) using nonpathogenic Streptomyces strains to suppress CS in a field situation.
Methods and Results
Nonpathogenic Streptomyces strains that had shown potential for mitigating CS in greenhouse assays were used in Michigan and Pennsylvania fields known to have high CS disease pressure. Five biocontrol (BC) strains and three potato cultivars were used in 2009, and three BC strains and three cultivars were used in 2010 in each location. The effects of BC strains on CS disease incidence and severity differed between locations, years and potato cultivars. When overall means of individual BC treatments were compared with nontreated controls, CS incidence and severity were decreased by all BC strains in PA2009, PA2010 and MI2010, particularly in cultivar ‘Yukon Gold’ in MI. Biocontrol treatments also significantly shifted the proportions of superficial, raised and pitted lesion types in some cultivar/biocontrol treatment combinations.
All BC strains significantly reduced CS incidence and severity on ‘Yukon Gold’ in three of four trials, and one BC strain significantly improved the lesion severity profile in cultivar ‘Atlantic’. No BC strain significantly reduced CS incidence and severity on all potato cultivars in the different years and locations.
Significance and Impact of the Study
Several nonpathogenic Streptomyces strains showed potential to reduce CS incidence and severity on two important potato-chipping cultivars in the field. These results can be further applied to reduce CS disease severity in potatoes.