Management of thrips in a hydroponic strawberry crop near Sydney, New South Wales, was studied from 1999 to 2002. The main species present were western flower thrips, Frankliniella occidentalis (Pergande), plague thrips, Thrips imaginis Bagnall, and, occasionally, onion thrips, Thrips tabaci Lindeman. Their within-and between-plant distribution and the degree and type of damage caused are described, and used to recommend action thresholds. Flowers are identified as the primary monitoring site, and young green fruit as the key damage site. Action thresholds of approximately 45% of flowers with 5 or more adult western flower thrips, or 40% of flowers with 10 or more adult plague thrips are recommended. Alternative thresholds using all motile stages are given for flowers, and for young green and red berries. A higher tolerance is recommended during cool, wet periods.

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The biology of the Australian phytoseiid mite Typhlodromips montdorensis is described from material collected in Queensland and South Australia in 1994−1996. At 25°C, when fed on cumbungi (Typha sp.) pollen, the life cycle was completed in approximately 7 days, with an intrinsic rate of natural increase (rm) of 0.32. Female−male pairs produced a mean total of 52.7 eggs within 28 days of oviposition. Females that were deprived of males after first mating stopped laying eggs after 7−19 days; however, if another male was added, they resumed egg laying and produced, on average, a total of 49.4 eggs. The sex ratio was 2.24 females to one male. At 25°C, fecundity on a diet of thrips larvae (first‐instar Frankliniella schultzei Trybom) was high, ranging from 2.72 to 3.58 eggs per day on the third day, depending on previous diet. Consumption rate of thrips was also high, with an average of 7.23−14.44 first‐instar larvae eaten per day on the third day, depending again on previous diet and also on number of thrips larvae made available. The species was also observed to feed on: (i) broad mite, Polyphago­tarsonemus latus (Banks); (ii) tomato russet mite, Aculops lycopersici (Massee); and (iii) two‐spotted mite, Tetranychus urticae Koch. No diapause was observed under conditions of 25°C, 8 h light and 10°C, 16 h dark. Eggs were sensitive to low humidity, with 50% failing to hatch below 70.8% relative humidity. This species is of interest as a candidate biological control agent for thrips, broad mite and tomato russet mite in protected crops.

The predatory mites Phytoseiulus persimilis Athias-Henriot and Amblyseius cucumeris Oudemans, and the parasitoid wasp Encarsia formosa Gahan are used in Alberta greenhouses in biological control programs to control spider mite, thrips, and whiteflies respectively. Following persistent complaints from growers in 1989 and 1990 about poor quality and lack of efficacy, several shipments from three commercial suppliers were evaluated in 1991. In the case of shipments of P. persimilis and A. cucumeris, there was significant divergence from stated contents both among suppliers and among batches. In laboratory tests for survival and fecundity, predator mites from most batches performed poorly. Emergence of E. formosa from parasitized whitefly pupae was generally low and less than 60 percent. Samples from the shipments were examined for the presence of microorganisms that might cause disease. Several of possible significance were found, including rickettsia, micro sporidia, and virus, all previously undescribed.The poor performance of some shipments is discussed in relation to possible causes such as shipping stress, starvation, improper storage, and disease. IX 'V., V .r-'vst* i ' A,,^-V .-.O' Vf U;i i"'/^} 7m0%S 'K v4' r^'^' M '4HHI '" AM'ktM'^iJM:-.

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