Previous studies conducted in our laboratory showed that transgenic medaka expressing cecropin B transgenes exhibited resistant characteristic to fish bacterial pathogens, Pseudomonas fluorescens and Vibrio anguillarum. To confirm whether antimicrobial peptide gene will also exhibit anti-bacterial and anti-viral characteristics in aquaculture important fish species, we produced transgenic rainbow trout expressing cecropin P1 or a synthetic cecropin B analog, CF-17, transgene by sperm-mediated gene transfer method. About 30 % of fish recovered from electroporation were shown to carry the transgene as determined by polymerase chain reaction (PCR) amplification assay. Positive P1 transgenic fish were crossed to non-transgenic fish to establish F1 transgenic founder families, and subsequently generating F2, and F3 progeny. Expression of cecropin P1 and CF-17 transgenes was detected in transgenic fish by reverse transcription (RT)-PCR analysis. The distribution of body sizes among F1 transgenic fish were not significantly different from those of non-transgenic fish. Results of challenge studies revealed that many families of F2 and F3 transgenic fish exhibited resistance to infection by Aeromonas salmonicida and infectious hematopoietic necrosis virus (IHNV). All-male homozygous cecropin P1 transgenic families were produced by androgenesis from sperm of F3 heterozygous transgenic fish in one generation. The resistant characteristic to A. salmonicida was confirmed in progeny derived from the outcross of all-male fish to non-transgenic females. Results of our current studies confirmed the possibility of producing disease-resistant homozygous rainbow trout strains by transgenesis of cecropin P1 or CF-17 gene and followed by androgenesis.

Epiphyas postvittana (Walker) resistant to azinphos-meth yl caused 1.7 and 5.4 % fruit damage in 1983/84 and 1985/86 in apple orchards at Moutere Bluffs, New Zealand. Surveys from 1984 to 1989 of resistance in orchards and scrub nearby showed 3.5% survival of the diagnostic dose (LD 99. 9S) in January and 7.6 % survival in April. Survival did not increase between years. Catches in pheromone traps inside affected orchards indicated high levels of male activity despite regular application of chlO1llyrifos. Mating disruption, along with the application of chlorpyrifos, was investigated as a possible solution to the continued inability to achieve economically acceptable leaf roller control with insecticides alone. Two ha of apple trees were treated with Shin Etsu Chemical Co. dispensers (1000/ha)containing(E)-II-tetradecenylacetateand (E,E)-9.II-tetradecadien-I-yl acetate (56.5 and 2.8 mg per dispenser). in January 1987. No males were caught for over 11 months after the pheromone application. Harvest damage of the apple variety 'Sturmer Pippin' by lightbrown apple moth in the 1986/87 season was reduced to 0.02% from 5.4% in 1985/86. In January 1988, dispensers were applied at the same application rate in the same area, and one less chlorpyrifos application was made (total of 10). At H90004

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