摘要

Japan has phytosanitary and quarantine measures that require hay shipments to be inspected for host plants or disinfested from Hessian fly [Mayetiola destructor (Say)] puparia Canadian hay exporters would prefer disinfesting the hay before shipping since it is more viable and economical than the inspection method Field tests were conducted in the summer of 2007 to investigate the effect of compression pressure, storage time, and hay properties on the disinfestation of Hessian fly puparia Four different timothy hay lots (first-cut hay at low moisture content (M(1)), first-cut hay at high moisture content (M(2)), second-cut hay at low moisture content (M(3)), and second-cut hay at high moisture content (M(4)) were compressed (re-baled) at two pressures of 10 34 and 12 41 MPa The bales were stored for 0 5 h, 24 h, 168 h (1 week), 336 h (2 weeks), and 504 h (3 weeks) For storage times 168, 336, and 504 h, the compressed bales were stored in a container to simulate storage and shipping conditions Four out of 112,000 puparia survived to adulthood in the bales stored for 0 5 and 24 h and compressed at low pressure of 10 34 MPa However, there was no survival in any of the high pressure (12 41 MPa) treatments or in the bales stored for 168, 336, and 504 h (1, 2, and 3 weeks) treated at lower compression pressure (10 34 MPa) This result also shows that bales when compressed and stored under dry conditions for a period of 1 to 3 weeks should be an effective quarantine method for shipping re-baled hay from Canada to Japan The hay characteristics had no effect on the disinfestation since the emergence of Hessian flies was found both in high moisture content and in low moisture content bales, and in first cut and second cut hay as well