Resistance to Wheat Curl Mite (Acari: Eriophyidae) in Greenbug-Resistant ‘Gaucho’ Triticale and ‘Gaucho’ X Wheat Crosses

Abstract

Greenbug-resistant “Insave F.A.” rye, “Gaucho” triticale, and crosses of Gaucho x wheat. Sel. 74G80-2 and Sel. 74G559-6, were compared with wheat cultivars for their reaction to the wheat curl mite, Eriophyes tulipae Keifer, the vector of wheat streak mosaic virus. It was previously observed that rye generally is more resistant to the mite than wheat. In our study, Gaucho, which is the product of an Insave F.A. rye X ‘Chinese Spring’ wheat cross, and wheat lines derived from Gaucho X wheat crosses, showed a high degree of resistance to the mite, whereas the susceptible entries exhibited severe mite damage symptoms including leaf curling and trapping and large numbers of mites. The wheat streak mosaic virus was transmitted to all test entries by heavy initial infestations of viruliferous mites. Light infestations of 5 mites per plant did not result in disease symptoms, except in mite-susceptible entries. The results also indicate that the source of wheat curl mite resistance in ‘TAM 107’ wheat, widely planted in wheat streak virus-prone areas of the Great Plains, traces back to Gaucho triticale.