Populations of adult male southern corn rootworms (SCR) were monitored, and percent pod damage evaluated, for 107 peanut fields in the peanut growing regions of northeastern North Carolina and southeastern Virginia from 1986 through 1990. percent pod damage was not consistently related to numbers of adult male SCR as determined by pheromone trap catches, for any of the five years, or for all five years combined. However, fields with trap catches less than or equal to 45 beetles per trap per week (17% of those sampled) appeared to be at low risk for SCR damage. When SCR numbers averaged less than 45 beetles per trap per week, percent pod damage averaged less than 3% and variation was low (standard deviation=2.1%), indicating that this number may be used as a low-end cutoff for SCR treatment. The critical dependence of SCR on adequate soil moisture for survival of eggs and early instar larvae may be a major factor contributing to the lack of correlation between numbers of adult SCR and damage to peanut pods under field conditions.
1Contribution of the North Carolina Agricultural Research Service and the Virginia Cooperative Extension Service. Partially funded by a grant from the North Carolina Peanut Growers Association, Inc. and the Virginia Peanut Growers Association.