Effects of Crop Rotation and Biocontrol Amendments on Rhizoctonia Disease of Potato and Soil Microbial Communities

Abstract

Rotation crops and biocontrol amendments were investigated for suppression of Rhizoctonia solani on potato (Solanum tuberosum) and their interactive effects on soil microbial communities. Greenhouse trials were conducted to evaluate selected rotation crops, including barley, common and “Lemtal” ryegrass, clover, potato, and combinations of barley with ryegrass or clover, for their effects on populations of R. solani and Rhizoctonia disease. Potato and clover preceding potato resulted in higher disease severity than most other rotations, whereas ryegrass reduced stem canker severity. In addition, all ryegrass treatments resulted in substantially higher populations of R. zeae. Field trials evaluating selected biocontrol treatments in combination with different rotations were conducted at two locations in Maine. Potatoes were treated with the biocontrol organisms Laetisaria arvalis, Trichoderma virens, or Bacillus subtilis and planted following rotation crops of barley and ryegrass, barley and clover, or potato. The barley/ryegrass rotation significantly reduced incidence and severity of stem canker and increased tuber yield at one location. Efficacy of the biocontrol treatments varied by rotation and location, with L. arvalis and T. virens reducing black scurf in some rotations and increasing some aspects of tuber yield at one location. Soil microbial community characteristics differed among rotation crops and biocontrol treatments. Significant crop by biocontrol interactions were observed demonstrating the complex interactions among rotation crops, biocontrol treatments, and soil microbial communities, as well as indicating that biocontrol can be enhanced within beneficial rotations.

Irreplaceable Role of Amendment-Based Strategies to Enhance Soil Health and Disease Suppression in Potato Production

“…Crop rotation has multiple benefits, as it impacts physical soil properties and reduces soil erosion. Equally importantly, it reduces soilborne pathogens by disease-suppressive or non-host crops, and enhances beneficial microorganisms and overall soil health [ 39 , 51 , 53 , 54 ]. Commonly used crops for rotation in potato production include, but are not limited to, Brassica crops (e.g., horseradish, mustard, broccoli, turnip, canola, radish, and wasabi), grain crops (e.g., barley, wheat, oat, maize, Sudan grass, ryegrass and rye), legumes (alfalfa, clover, peas, vetch), and beets ( Table 1 , Figure 2 ).…”

“…Broad beans affect soil microbial communities, diversity and crop yield in a long-term continuous potato cropping field [ 56 ]. In summary, rotation crops are selected based on the criteria that they are (1) non-host cash crops; (2) economically viable options; (3) crops containing substances such as antimicrobial activities [ 22 , 27 , 53 , 57 ].…”

A Critical Review of Research on Exploitation of Microbial Antagonists for the Control of Bacterial Diseases in Crop Plants

“…Some enzymes of PR proteins are enhanced the host defense system against various types of infections by directly lyse invading cells, strengthen cell wall boundaries, or cause localized cell death. Jasmonic acid (JA) and ethylene are involved in another phenotype known as induced systemic resistance (ISR) which is produced after some nonpathogenic rhizobacteria (Larkin et al, 2020;Kohl et al, 2019, Mauch-Mani et al, 2017Reithner et al, 2011). Amazingly, the ISR pathway may be antagonistic because some bacterial pathogens use this to avoid SAR.…”

“…The disease suppression can be incurred in many ways depending on the plant disease type, e.g. the use of crop rotation and plantation of different resistant cultivars or, in a narrower perspective, utilizing resident living organisms could also be regarded as biological control (Larkin and Brewer, 2020).…”

Effect of organic and conventional farming on soil bacterial diversity of pecan tree ( Carya illinoensis K. Kosh) orchard across two phenological stages

“…2015), which also influence the microbial community and its metabolic capacities (Lauga et al . 2013; Larkin and Brewer 2020). Understanding the microbial community dynamics will provide useful information to manage soil quality (Siebers et al .…”