How to translate text using browser tools
1 June 2015 An Induced Susceptibility Response in Soybean Promotes Avirulent Aphis glycines (Hemiptera: Aphididae) Populations on Resistant Soybean
A. J. Varenhorst, M. T. McCarville, M. E. O'Neal
Author Affiliations +
Abstract

Observations of virulent Aphis glycines Matsumura populations on resistant soybean in North America occurred prior to the commercial release of Rag genes. Laboratory assays confirmed the presence of four A. glycines biotypes in North America defined by their virulence to the Rag1 and Rag2 genes. Avirulent and virulent biotypes can co-occur and potentially interact on soybean, which may result in induced susceptibility. We conducted a series of experiments to determine if the survival of avirulent biotypes on susceptible and resistant soybean containing the Rag1 or Rag1 Rag2 genes was affected by the presence of either avirulent or virulent conspecifics. Regardless of virulence to Rag genes, initial feeding by conspecifics increased the survival of subsequent A. glycines populations on both susceptible and resistant soybean. Avirulent populations increased at the same rate as virulent populations if the resistant plants were initially colonized with virulent aphids. These results are the first to demonstrate that virulent A. glycines increase the suitability of resistant soybean for avirulent conspecifics, thus explaining the lack of genetic differentiation observed in North America between A. glycines populations on resistant and susceptible soybean. These results suggest the occurrence of virulence toward Rag genes in North America may be overestimated. In addition this may alter the selection pressure for virulence genes to increase in a population. Therefore, insect resistance management models for A. glycines may need to incorporate induced susceptibility factors to determine the relative durability of resistance genes.

© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com
A. J. Varenhorst, M. T. McCarville, and M. E. O'Neal "An Induced Susceptibility Response in Soybean Promotes Avirulent Aphis glycines (Hemiptera: Aphididae) Populations on Resistant Soybean," Environmental Entomology 44(3), 658-667, (1 June 2015). https://doi.org/10.1093/ee/nvv051
Received: 24 July 2014; Accepted: 20 March 2015; Published: 1 June 2015
JOURNAL ARTICLE
10 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

KEYWORDS
feeding facilitation
host plant resistance
obviation of resistance
Rag genes
soybean aphid
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top