BLISTER BEETLES (COLEOPTERA, MELOIDAE) IN KANSAS ALFALFA - INFLUENCE OF PLANT PHENOLOGY AND PROXIMITY TO FIELD EDGE

Survey of Epicauta spp., infesting Medicago sativa assessed the influence of in-field location, harvest cycle, and host phenological stage on insect density. Densities of beetles were very low during the 1st and 5th harvest cycles, suggesting that hay from these cuttings has lower cantharidin contamination risk and, therefore, requires minimal blister beetle management. Significant differences among strata were observed when blister beetles were summed over all phenological stages within 2nd, 3rd and 4th harvest cycles. Blister beetle densities varied significantly among 3 in-field and 1 noncropped strata during vegetative, bud and bloom phenological stages of the 2nd harvest cycle and in bud and bloom stages of the 3rd harvest cycle. Significantly lower numbers of blister beetles per field were observed in vegetative-stage alfalfa during harvest cycles 2, 3 and 4. Blister beetles tended to occur with slightly to significantly greater frequency in alfalfa sampled 3 m into the field. -from Authors