2007 Annual Report 1a.Objectives (from AD-416) Develop the potential of entomopathogenic fungi for microbial control of pear thrips in forests and western flower thrips in greenhouses as part of a comprehensive IPM strategy. 1b.Approach (from AD-416) Candidate fungal isolates will be investigated as to their growth and mass-production capabilities, their compatibility with chemical and biorational pesticides and non-target natural enemies. Other IPM strategies, such as fallowing greenhouses or screening vents will be assessed and pear thrips population patterns determined as factors that affect fungal efficacy and thrips suppression. In addition, spray application methods and the effect of timing in forest or greenhouse treatments will be evaluated to optimize application techniques that promote fungal efficacy and pest suppression. 3.Progress Report Research continues on using fungal pathogens to control pear thrips (PT; Taeniothrips inconsequens; pests of sugar maples in Vermont) and Western flower thrips (WFT; Frankliniella occidentalis, a major pest in greenhouses nationwide) using the fungi Beauveria bassiana, Metarhizium anisopliae, and Lecanicillium lecanii. Experimental fungal spray applications are monitored efficiently and are being optimized by removing spores from plant surfaces with two types of commercially available transparent plastic tapes. In greenhouse studies, mortalities of WFT can exceed 97% with Metarhizium, and are 67-70% with Beauveria and Lecanicillium. Metarhizium yields higher mortalities and notably faster kills of thrips with less overall damage to host plants than do the other fungi tested; the speed of kill is especially important for hosts such as thrips with very short life cycles. For greenhouse production of ornamental plants, separate experimental protocols (including the use of fungal biocontrols) for 'best management practices' (BMP) and 'conventional' (CON) pest management practices were developed and are being tested for overall effectiveness in pest management and the overall economics of each approach. The BMP approach includes the use of more extensive surveys for pests as well as placements of 'banker' plants to build populations of predatory wasps (on barley grass with a grass-limited host aphid population) or predatory mites (on marigolds and pepper plants); such 'banker' plants may eventually contribute to the build-up of WFT populations unless the WFT populations on these plants are treated. Marigolds were useful indicator plants allowing earlier detections of low WFT populations than on many other plant types; the appearance of WFT on these indicators can be used to trigger other fungal or chemical control treatments in either BMP or CON systems. Elite isolates of Beauveria and Metarhizium for use in these greenhouse tests were produced on granular or liquid whey-based growth media as well as on millet grains. The activities of these isolates against WFT and predatory mites were tested, as was persistence of whey-based formulations on bean plants in greenhouse conditions. Control of WFT with whey-grown fungi exceeded 80%, and spores of these fungi remained viable longer, caused higher mortality rates than with water-based formulations, and also appear to tolerate high temperature stresses (45 degC) better. Predatory mites are not badly affected by these whey-based Beauveria and Metarhizium treatments. Whey-and millet-based granules were producible in 3-4 days, can be stored for 240 days at 4 or 40 deg C, and form infective, highly viable conidia after 3 days post-storage incubation in damp chambers. Applying fungal granules in or onto soil or potting medium reduced WFT emergence by 82-92%; saprobic growth in amended soils led to increased fungal inoculum levels. Early greenhouse studies of Beauveria or Metarhizium granules applied to soils reduced WFT populations by 34-78% or 9-56% in comparison to the controls, respectively. ADOR communicated with project cooperators by phone, throughout the year, and by on-site visit (April 2007).