Evaluation of Rhizoctonia solani - Heterodera glycines interactions on soybean
type: CreativeWork
description: Rhizoctonia solani and the soybean cyst nematode (Heterodera glycines; SCN) are two soilborne pathogens that co-infest fields in soybean-producing states, contributing to significant yield reduction. Both pathogens infect the soybean radicle early in the growing season causing pre- and post-emergence stand reductions. The pathogens thrive in analogous environments, suggesting the potential for an interaction. Field and greenhouse studies were conducted to evaluate four fungicide seed treatments in multiple combinations to evaluate this interaction as well as early season control of the pathogens. Seed treatments were applied to soybean cultivars that were resistant and susceptible to SCN. Field studies were conducted at two Illinois locations (Urbana and Carmi). In 2009, 2010, and 2011, at Urbana, IL and in 2011 at Carmi, IL, SCN HG type 2.5.7 occurred naturally, and natural R. solani pressure in the soil was augmented with sterilized grain sorghum colonized by R. solani. Soil samples were collected at spring planting and after fall harvest to determine SCN reproduction. Soybean stand was evaluated, and roots from the field were collected for digital scanning and root analysis to measure disease symptom severity at the V1 growth stage. R. solani root lesions were rated on a 0-5 scale at the V1 stage and used to produce a root rot index. At the end of the season, harvest data were collected. An infestation evaluation and a seed treatment evaluation were conducted in the greenhouse. In the infestation evaluation, infestations with both a R. solani mycelial suspension and SCN HG type 2.5.7. population at zero, low, and high levels on resistant (S35-T9) and susceptible cultivars (S36-B6) were evaluated. In the seed treatment evaluation, high levels of the mycelial suspension and SCN population were used to infest plots at planting to evaluate the control of four fungicide seed treatment combinations on resistant and susceptible cultivars. Initial plant emergence and sus…
abstract: Rhizoctonia solani and the soybean cyst nematode (Heterodera glycines; SCN) are two soilborne pathogens that co-infest fields in soybean-producing states, contributing to significant yield reduction. Both pathogens infect the soybean radicle early in the growing season causing pre- and post-emergence stand reductions. The pathogens thrive in analogous environments, suggesting the potential for an interaction. Field and greenhouse studies were conducted to evaluate four fungicide seed treatments in multiple combinations to evaluate this interaction as well as early season control of the pathogens. Seed treatments were applied to soybean cultivars that were resistant and susceptible to SCN. Field studies were conducted at two Illinois locations (Urbana and Carmi). In 2009, 2010, and 2011, at Urbana, IL and in 2011 at Carmi, IL, SCN HG type 2.5.7 occurred naturally, and natural R. solani pressure in the soil was augmented with sterilized grain sorghum colonized by R. solani. Soil samples were collected at spring planting and after fall harvest to determine SCN reproduction. Soybean stand was evaluated, and roots from the field were collected for digital scanning and root analysis to measure disease symptom severity at the V1 growth stage. R. solani root lesions were rated on a 0-5 scale at the V1 stage and used to produce a root rot index. At the end of the season, harvest data were collected. An infestation evaluation and a seed treatment evaluation were conducted in the greenhouse. In the infestation evaluation, infestations with both a R. solani mycelial suspension and SCN HG type 2.5.7. population at zero, low, and high levels on resistant (S35-T9) and susceptible cultivars (S36-B6) were evaluated. In the seed treatment evaluation, high levels of the mycelial suspension and SCN population were used to infest plots at planting to evaluate the control of four fungicide seed treatment combinations on resistant and susceptible cultivars. Initial plant emergence and sus…
author: Frohning, Jessica
language: en
keywords: Rhizoctonia, Rhizoctonia solani, Heterodera glycines, Heterodera, soybean cyst nematode (SCN), soybean disease, AG 2-2, HG type 2.5.7, fungicide, seed treatment, sedaxane, mefenoxam, abamectin, Bradley, Frohning
date published: 2013-05-24T21:55:17Z
date modified: 2026-07-22T22:25:33Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois at Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/44241