ADAPTATION OF WHEAT CURL MITE (ACARI, ERIOPHYIDAE) TO RESISTANT WHEATIN KANSAS

Wheat streak mosaic (WSM) was the most important disease of wheat, Tri ticum aestivum L., in Kansas from 1987 to 1991. The incidence of WSM i s reduced in the wheat cultivar TAM 107, which has resistance to the w heat curl mite, Eriophyes tulipae Keifer, vector of the WSM virus. Our objectives were to determine whether E. tulipae could overcome the re sistance of TAM 107 in the laboratory and to look for evidence of a re sistance-breaking strain on TAM 107 in the field. E. tulipae was able to overcome resistance after being reared on TAM 107 for 2 mo. (ca. 8 generations) under laboratory conditions. One of 10 1992 field collect ions of E. tulipae from spikes of TAM 107 was adapted to that cultivar . Thus, E. tulipae can develop a resistance-breaking strain in both fi eld and laboratory, but more information is needed on its prevalence a nd distribution in the field.