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Methyl salicylate (MeSA), a herbivore-induced plant volatile, can elicit control of pests through attraction of beneficial arthropods. This study evaluates the effect of synthetic MeSA lures (PredaLure) on arthropod populations during the 2009 and 2010 seasons in two Oregon vineyards (Dayton and Salem). MeSA lures were deployed at a low (4/plot or 260 lures/ha) and high (8/plot or 520 lures/ha) rate in 152 m 2 plots while control plots contained no lure. The predatory mite Typhlodromus pyri Scheuten is considered to be a key biological control agent of the grapevine rust mite, Calepitrimerus vitis Nalepa in Oregon vineyards. Leaf samples were collected to assess T. pyri, C. vitis, spider mite (Tetranychidae) and thrips (Thripidae) population densities in MeSA treated plots compared to control plots. Yellow sticky traps were used to monitor other key predator groups including Anthocoridae, Araneae, Coccinellidae and Syrphidae. Our data did not display consistent trends in T. pyri response to MeSA between treatments at the two field sites over two seasons. Mean seasonal coccinellid counts were significantly higher in MeSA treatments in both years at Dayton. No differences in C. vitis population densities were found between treatments in both years. In 2009 at Salem, significantly lower pest thrips densities occurred in low rate MeSA treatments in the latter part of the season although no trend of decreased seasonal abundance was evident.

The African parasitoid Psyttalia lounsburyi (Silvestri) was evaluated as part of a classical biological control program directed at the olive fruit fly, Bactrocera oleae (Rossi), in California, USA. Experimental assessment using three non-target species provided some evidence that P. lounsburyi restricts its host use to B. oleae. Female P. lounsburyi preferentially searched olives infested with mature third-instar B. oleae, over other non-target plants, but most offspring were reared from olives containing younger (second through young third instar) B. oleae larvae. Developmental time (egg to adult) and adult longevity were significantly affected by temperature and sex, with males tending to develop faster and females living longer, especially in the lower ranges of temperatures tested. The mean longevity of adult female P. lounsburyi was greatest when honey was available and lowest when they were provided water alone or nothing. The presence of hosts significantly decreased longevity. Females produced an average of 10.2 ± 2.6 progeny during their lifetimes, which was lower than expected for a parasitoid adapted to B. oleae and may be a consequence of increased fruit size—the result of cultivation and selection—reducing parasitoid effectiveness on cultivated vs. wild fruit, as well as constraints on oviposition behavior imposed by experimental design. The results are discussed with respect to the use of P. lounsburyi as a biological control agent for olive fruit fly in California.

The influence of temperature on Anagyrus pseudococci (Girault) development and overwintering was investigated to improve biological control of the vine mealybug, Planococcus ficus (Signoret), in California vineyards. At a constant 32 °C, egg development required 2 days, larval development ranged from 0.7 ± 0.1 (second instar) to 1.9 ± 0.1 (fifth instar) days, and pupal development was 3.9 ± 0.1 days. Under eight constant temperatures (12, 14, 17, 22, 27, 32, 34, and 36 °C), A. pseudococci completed development (egg to adult eclosion) from 14 to 34 °C. Development times ranged from 79.1 ± 1.0 days (14 °C) to 10.2 ± 0.3 days (34 °C). We determined optimal, maximum and minimum development temperatures to be 24.7, 36.0 and 11.6 °C, respectively, and the thermal constant is 223.5 degree-days. We compared these laboratory-derived temperature relationships to A. pseudococci field-monitored populations from March through November. Laboratory-data suggests there are seven to eight A. pseudococci generations during this period, two generations to each vine mealybug generation. Overwintering studies show that A. pseudococci emergence was concentrated over a 15 day period in early May, regardless of when vine mealybugs were exposed (October 2001 to March 2002). Results suggest that cues other than temperature are used to synchronize overwintered A. pseudococci adult emergence with field availability of vine mealybug.