Russian Wheat Aphid Survey in Southeastern Arizona, 1990

Abstract

Fifteen small grain fields, including eight wheat fields, two barley fields and five oat fields, throughout the grain growing areas of Graham, Greenlee and Cochise counties were surveyed weekly from the third week in March through the second week in June, to document the presence of Russian wheat aphid (RWA), other aphid, parasites and predators. RWA were found in all three counties and in all three grains. Presence of RWA caused chemical pest control applications in approximately 19%, 33% and 90% of the small grain fields in Graham, Greenlee and Cochise counties, respectively. Thirty three percent of the fields had beneficial parasites and predators were found 93% of the fields. Presence of parasites reduced the RWA populations in 80% of the cases and presence of predators had a dramatic effect on other aphids and was felt to be beneficial in controlling RWA.