The latest Arizona Vegetable Integrated Pest Management Update from the University of Arizona (UA) Cooperative Extension in Yuma, Ariz.

Bagrada bug seasonal activity

By John Palumbo, UA Research Scientist and Extension Specialist

It's been quite a while since we've received any calls concerning Bagrada bugs on local cole crops. In fact, we haven't seen any adults in the cabbage and broccoli plots at the Yuma Agricultural Center (YAC) since late January. This is not surprising considering the cool weather.

These observations are consistent with our experiences last spring when we didn't find our first Bagrada bug on spring cabbage until mid-April. However, last week we found a large number of Bagrada bug adults and nymphs aggregating within a small planting (0.15 ac) of untreated canola at the YAC. The canola plants are past full bloom and filling seed pods.

The bugs can be found walking within the canola on the ground and feeding damage can be found on older leaves. We presume this population is a result of adult and nymphs that migrated into the canola in December when an adjacent block of infested broccoli was disked under.

This should serve as a warning as Bagrada bugs are known to be a major pest of canola and Brassica seed crops in Pakistan and India. Pest control advisers and growers should monitor seed crops closely as the crops begin to mature.

Pay particular attention to the cracks and crevices in the soil underneath plants and in the furrow. I am not sure they will be an issue on seed crops, but there is still much we don’t know about this new pest in the desert.

Contact Palumbo: (928) 928-782-3836 or jpalumbo@ag.arizona.edu.