SUSCEPTIBILITY OF CEREAL AND NON-CEREAL GRASSES TO ATTACK BY HESSIAN FLY (MAYETIOLA-DESTRUCTOR (SAY))

The susceptibility of cereal, pasture, and wild grasses to attack by H essian fly (Mayetiola destructor (Say)) was investigated by quantifyin g egglaying responses of adult females and the growth and survival of feeding larvae. A wide range of attractiveness to egglaying adult fema les was observed, not only between grass species but also within grass species (e.g., wheat). Larval growth and development occurred on all of the New Zealand wheat cultivars, New Zealand barley cultivars, and New Zealand barley breeding lines that were tested. A small number of the United States wheat cultivars and New Zealand wheat breeding lines that were tested did not support the growth of larvae and therefore w ere resistant to Hessian fly. In addition to wheat and barley, Hessian fly laid eggs and survived as feeding larvae on couch, barley grass, and prairie grass (both wild and cultivated species of the latter). Re lative to wheat seedlings, seedlings of the cultivated prairie grass ( Bromus willdenowii 'Grasslands Matua'), appeared to be an inferior hos t; larvae feeding on wheat seedlings attained greater pupal weights th an larvae feeding on prairie grass seedlings.