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ARS Home » Southeast Area » Byron, Georgia » Fruit and Tree Nut Research » Research » Publications at this Location » Publication #131502

Title: MICROBIAL CONTROL RESEARCH FOR SUPPRESSION OF THE PECAN WEEVIL

Author
item Shapiro Ilan, David
item GARDNER, WAYNE - UNIVERSITY OF GEORGIA
item FUXA, JAMES - LSU, BATON ROUGH
item Wood, Bruce
item Cottrell, Ted
item NGUYEN, KHUONG - UNIVERSITY OF FLORIDA
item ADAMS, BYRON - UNIVERSITY OF FLORIDA
item Humber, Richard
item HALL, MICHAEL - LSU, SHREVEPORT

Submitted to: Pecan Western Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 2/16/2002
Publication Date: 4/1/2002
Citation: Shapiro Ilan, D.I., Gardner, W.A., Fuxa, J.R., Wood, B.W., Cottrell, T.E., Nguyen, K.B., Adams, B.J., Humber, R.A., Hall, M.J. 2002. Microbial control research for suppression of the pecan weevil. Pecan Western Conference Proceedings. p.2-15.

Interpretive Summary: The pecan weevil is a major pest of pecans throughout the Southeastern U.S. Currently, the insect is controlled by chemical insecticide sprays. Due to environmental and regulatory concerns, alternative methods of control must be sought. The use of insect diseases to kill harmful insect pests is a promising approach to the problem. The insect diseases, such as certain nematodes (tiny worms) and fungi, do not harm humans or the environment. This paper presents several studies that investigate the potential for using nematode and fungal diseases to kill the pecan weevil. Nematodes were found to be highly virulent to adult weevils but not to the immature stages. Fungi were virulent to both adults and immature stages. In a soil survey to find new strains of nematodes and fungi, a number of virulent fungal strains and some nematodes were discovered.

Technical Abstract: The pecan weevil, Curculio caryae, is a major pest of pecans throughout the Southeastern U.S. Currently, the insect is controlled by chemical insecticide sprays, e.g., Carbaryl. Due to environmental and regulatory concerns, alternative methods of control must be sought. Microbial control is a promising approach to the problem. Entomopathogenic nematodes (i.e., genera Steinernema and Heterorhabditis) and certain fungi (e.g., genera Beauveria and Metarhizium) appear to be most promising. This paper presents several studies that investigate the potential for microbial control of the pecan weevil. Nematodes were found to be highly virulent to adult weevils,especially S. carpocapsae, but not to the larvae. Fungi were virulent to both adults and immature stages. In a soil survey to find new strains of nematodes and fungi, a number of virulent fungal strains (Beauveria and Metarhizium) and some nematodes were discovered including H. bacteriophora, S. glaseri, S. carpocapsae, and the first report of S. rarum in the U.S.