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Hairy Chinch Bug Biology and Parasitoids in Ohio Mrs. Jennifer Andon Department of Entomology The Ohio State University Columbus, OH 2004-2006 • • Objectives Survey and document the annual populations of hairy chinch bugs and their egg parasitoid in Ohio lawn-type turf. Determine if HCB populations obtained from lawns being maintained at different levels of management vary in susceptibility to Beauveria bassiana infection. Why? Recent observations of hairy chinch bug populations appears to conflict with earlier studies. We have found HCB in irrigated lawns which were thought to be at low risk for infestation. The Culprit Blissus leucopterus hirtus Montandon Family: Blissidae Formerly: Lygaeidae Population Sampling Methods • Standard golf course cup cutter • U.S.A. standard sieve series • Berlese funnel EVALUATION OF BEAUVERIA SUSCEPTIBILITY Reared HCB colonies obtained from irrigated and nonirrigated lawns on sorghum in the greenhouse. • • • • • • Butyrate and Plexiglas cylinders Pro-mix Peat Moss 16 hrs day light 75° F day temp 70° F night temp Biology of Hairy Chinch Bug in Ohio 2004 & 2005 Data • • • • • • • Two generations per year Adults overwintered in lawns Oviposition began in early May 1st generation nymphs peaked in mid-June 1st generation adults began egg lay by mid-July 2nd generation adults observed in early September Reproductive diapause commenced in October, chinch bugs descend into thatch and debris Hairy Chinch Bug Populations in Ohio Ex: Niemczyk & Shetlar 2000 Hairy Chinch Bug Populations 2004 600 Variable TA /.099/6 TN /.099/6 TE /.099/6 500 # HCB/Sq Ft 400 300 200 100 0 April May June July August Sept Index Oct Nov Hairy Chinch Bug Populations 2005 4000 Variable Total Adults/sq. ft Total Nymphs/sq ft Total Eggs/sq ft # HCB/Sq Ft 3000 2000 1000 0 April May June July August Sept Oct Biological Pathogens, Parasites, Predators • Conserve Parasitoids and Predators – Homeowner agreed not to use insecticides during study. Scelionidae Eumicrosoma beneficum Scelionid Egg Parasitoid Scelionid adult inside HCB egg Parasitized and normal egg Other Natural Enemies Bigeyed Bugs Geocoridae Predators Beauveria bassiana Hairy Chinch Bug cadaver with B. bassiana. Beauveria bassiana • • • • • • • • Deuteromycetes “White Muscardine” Ubiquitous, soil-borne fungus Requires moist, warm conditions to sporulate Hyphae penetrate insect cuticle Toxin (beauvericin) relaeased to kill insect Mycelium proliferates inside insect Insect dies in 3-4 days Beauveria bassiana Study Except • • • High maintenance lawns, i.e., regular fertilization and irrigation, have been observed with HCB infestations Therefore, have populations of HCB become less susceptible to Beauveria infection? I will evaluate Botanigard ES, a commercial formulation of Beauveria bassiana and determine if varying susceptibility to B.b. has developed. Beauveria, and other microbes from infected cadaver Isolated culture of Beauveria bassiana Dilution Series Botanigard™ ES Enumeration 10-1 10-2 10-3 10-4 16 billion CFUs per ml of Botanigard ES 10 -5 10-6 What’s Next… • Challenge different HCB populations (recovered from different lawns) with fungal spores. • Repeat another field season of monitoring chinch bug populations. Acknowledgements – Thanks • • • • • • • • • OSU/OARDC OTF Bayer, FMC, The Scotts Co. Mark Grunkemeyer, Buckeye Ecocare Scott Jones, One Call Gary Chatriand, Laverlam Int’l Columbus Area Master Gardeners Dr. Dave Shetlar, Dan Digman Dr. Mike Boehm, Amy Niver