Monitoring seasonal dynamics of cotton infesting aphids and cotton leafroll dwarf virus spread in Alabama

Sunday, November 13, 2022

2:42 PM – 2:54 PM PT

Location: Vancouver Convention Centre, Meeting Room 202

Presenting Author(s)

Jessica B. Mahas

Research Associate
Auburn University
Auburn, Alabama

Co-Author(s)

JM

John W. Mahas

Graduate Research Assistant
Auburn University
Auburn, Alabama
CR

Charles Ray

Auburn University
Auburn, Alabama
AK

Adam Kesheimer

Auburn University
Auburn, Alabama
KC

Kassie Conner

Auburn University
Auburn, Alabama
AJ

Alana Lynn Jacobson

Auburn University
Auburn, Alabama

Cotton leafroll dwarf virus (CLRDV) was first identified to infect cotton, Gossypium hirsutum Linnaeus, in the southeastern U.S. in 2017. Aphis gossypii Glover is the only vector reported to transmit this virus to cotton, and is the only aphid species reported to annually infest cotton in the U.S. An additional seven aphid species have been reported to sporadically infest cotton but are not considered economic pests. These include Aphis craccivora Koch, Myzus persicae Sulzer, Rhopalosiphum rufiabdominale Sasaki, Macrosiphum euphorbiae Thomas, Protaphis middletonii Thomas, Aphis fabae Scopoli and Smythurodes betae Westwood. Research in India has shown CLRDV can be transmitted to chickpea by A. craccivora Koch, and M. persicae Sulzer, but the vector status of these two aphids in the U.S. is unknown. The objective of this study was to gain a better understanding of the seasonal dynamics of aphids reported to infest cotton, and determine when virus spread occurs in the landscape. Aphids were monitored weekly over a two- year period in three distinct regions of Alabama using yellow pan traps. CLRDV spread was monitored using healthy 2-3 true leaf cotton seedlings as sentinel plants that were deployed concurrent with weekly aphid traps during the cotton growing season. The number of aphid species captured, their seasonal abundance across regions, and how this coincides with the timing of CLRDV spread throughout 2020 and 2021 will be discussed.