Tuesday, December 11, 2001 -

Parameters of Serratia marcescens transmission by the squash bug, Anasa tristis

Blake Bextine1, A. Wayadande1, Sam D. Pair2, B.D. Bruton2, Forrest L. Mitchell3, and J. Fletcher1. (1) Oklahoma State University, Department of Entomology and Plant Pathology, 127 NRC, Stillwater, OK, (2) USDA ARS, SCARL, Wes Watkins Agricultural Research and Extension Center, Lane, OK, (3) Texas A&M University, Research & Extension Center, 1229 North U.S. Highway 281, Stephenville, TX

Yellow vine disease (YV) of cucurbits causes chlorosis, rapid wilting and death of squash, pumpkin, watermelon and cantaloupe. The causal bacterium, Serratia marcescens (Sm), colonizes the plant phloem and can be transmitted by the squash bug, Anasa tristis. Since squash bugs have not been implicated previously as vectors of phytopathogens, identification of the mode of transmission is important. In this study a 24 h acquisition access period (AAP) was adequate for squash bug acquisition from bacteria-infiltrated squash cubes, and the bacterium could be transmitted to artificial feeding sachets or to plants within 24 h. A. tristis was able to transmit for at least 20 d, with most transmissions occurring between 2 and 7 d post-AAP. The insects retained Sm for at least 21 d, the duration of the experiments. From 20-60% of single inoculative squash bugs transmitted the bacterium. Eggs laid by Sm-transmitting females tested negative by Sm-specific PCR, suggesting that transovarial transmission does not occur.

Species 1: Hemiptera coreidae Anasa tristis (squash bug)
Keywords: Yellow vine, cucurbit

The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA