Spotted wing drosophila, Drosophila suzukii, is a globally invasive pest of soft-skinned fruit. Females oviposit into ripening fruit and larvae cause direct destruction of tissues. As many plant essential oils are permitted food additives, they may provide a safe means of protecting fruit from D. suzukii infestation in both conventional and organic production systems. Twelve oils and potassium metabisulfite (KMS) were screened in the laboratory as repellents for D. suzukii flies. Most essential oils deterred D. suzukii flies from cotton wicks containing attractive raspberry juice. Peppermint oil was particularly effective, preventing almost all flies from contacting treated wicks and remaining 100% repellent for 6 d post-application. Thyme oil was unique because it caused high male mortality and reduced the number of responding flies compared to other oils. KMS was not found to be repellent to D. suzukii, but may have fumigant properties, particularly at high concentrations. Peppermint oil appears to be the best candidate for field testing to determine the effectiveness and feasibility of using essential oils as part of a push-pull management strategy against D. suzukii. This is the first time that essential oils have been evaluated and proven effective in preventing fruit-infesting flies from contacting attractive stimuli.

Wild and managed bees provide effective crop pollination services worldwide. Protected cropping conditions are thought to alter the ambient environmental conditions in which pollinators forage for flowers, yet few studies have compared conditions at the edges and center of growing tunnels. We measured environmental variables (temperature, relative humidity, wind speed, white light, and UV light) and surveyed activity of the managed honey bee, Apis mellifera L.; wild stingless bee, Tetragonula carbonaria Smith; and wild sweat bee, Homalictus urbanus Smith, along the length of 32 multiple open-ended polyethylene growing tunnels. These were spaced across 12 blocks at two commercial berry farms, in Coffs Harbour, New South Wales and Walkamin, North Queensland, Australia. Berry yield, fresh weight, and other quality metrics were recorded at discrete increments along the length of the tunnels. We found a higher abundance and greater number of flower visits by stingless bees and honey bees at the end of tunnels, and less frequent visits to flowers toward the middle of tunnels. The center of tunnels experienced higher temperatures and reduced wind speed. In raspberry, fruit shape was improved with greater pollinator abundance and was susceptible to higher temperatures. In blueberry, per plant yield and mean berry weight were positively associated with pollinator abundance and were lower at the center of tunnels than at the edge. Fruit quality (crumbliness) in raspberries was improved with a greater number of visits by sweat bees, who were not as susceptible to climatic conditions within tunnels. Understanding bee foraging behavior and changes to yield under protected cropping conditions is critical to inform the appropriate design of polytunnels, aid pollinator management within them, and increase economic gains in commercial berry crops.

15Wild and managed bees provide effective crop pollination services worldwide. Protected 16 cropping conditions are thought to alter the ambient environmental conditions in which 17 pollinators forage for flowers, yet few studies have compared conditions at the edges and 18 centre of growing tunnels. We measured environmental variables (temperature, relative 19 humidity, wind speed, white light and UV light) and surveyed the activity of managed 20 honeybees Apis mellifera, wild stingless bees Tetragonula carbonaria and sweat bees 21Homalictus urbanus along the length of 32 multiple open-ended polyethylene growing 22 tunnels. These were spaced across 12 blocks at two commercial berry farms, in Coffs 23Harbour, New South Wales and Walkamin, North Queensland, Australia. Berry yield, fresh 24 weight and other quality metrics were recorded at discrete increments along the length of the 25 tunnels. We found a higher abundance and greater number of flower visits by stingless bees 26 and honeybees at the end of tunnels, and less frequent visits to flowers toward the middle of 27 tunnels. The centre of tunnels experienced higher temperatures and reduced wind speed. In 28 raspberry, fruit shape was improved with greater pollinator abundance and was susceptible to 29 higher temperatures. In blueberry, per plant yield and mean berry weight were positively 30 associated with pollinator abundance and were lower at the centre of tunnels than at the edge. 31Fruit quality (crumbliness) in raspberries was improved with a greater number of visits by 32 sweat bees, who were not as susceptible to climatic conditions within tunnels. Understanding 33 bee foraging behaviour and changes to yield under protected cropping conditions is critical to 34 inform the appropriate design of polytunnels and aid pollinator management within them. 35 36

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The use of drought-tolerant rootstocks is an important strategy in maintaining orchard productivity while meeting the increasing need to conserve water resources. The drought tolerance of two new genotypes, Vineland 1 (V.1) and Vineland 3 (V.3), was assessed along with industry standards to test the hypothesis that differences in water-use efficiency exist among these apple rootstocks. One-year-old, non-grafted nursery liners of M.9, MM.111, V.1, and V.3 were grown in a controlled-environment experiment. Plants of each genotype were maintained water-replete or were subjected to a 9-d controlled dry down and then maintained under water stress conditions for 55 d. Water stress reduced biomass accumulation and trunk cross-sectional area for all four genotypes. The two vigorous genotypes, MM.111 and V.1, increased their root-to-shoot ratios in response to water stress, whereas the root-to-shoot ratios of M.9 and V.3 remained unchanged in their water-replete controls. Genotype V.3 maintained its transpiration at a significantly lower soil water content compared to M.9, MM.111, and V.1. Of the four genotypes, V.3 demonstrated a high tolerance to water stress conditions, and therefore deserves further investigation using grafted apple trees in an orchard study.