Hanna McIntosh
entomologist, agroecologist
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PhD student developing practical solutions to fruit crop pest problems through interdisciplinary research
LATEST PROJECTS
Plastic & biodegradable mulch films for spotted-wing drosophila management
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Berry and soft-skinned fruit production world-wide experience substantial damage from the invasive fly spotted-wing drosophila (Drosophila suzukii). Management relies heavily on chemical control in organic and conventional agriculture. This is not economically or environmentally sustainable, and often does not provide adequate control of the pest.
I will take a broad, interdisciplinary, agroecological approach to assessing plastic and biodegradable mulch films as a cultural control for spotted-wing drosophila in raspberry. In addition to testing its viability for pest control, I aim to develop a nuanced understanding of the mulches’ broader agroecological impact on raspberry plants, fruit production, and soil health.
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This project includes on-farm experiments and a newly-established research plot. I am working closely with regional growers to make sure this project is relevant and useful. I have created a grower advisory panel to guide development, planning, and evaluation of this project.
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Suitability of frozen brown marmorated stink bug eggs for samurai wasp rearing & experimentation
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The brown marmorated stink bug (BMSB), Halyomorpha halys, has become a well-known pest to growers and homeowners since its 1996 introduction to the United States. A classical biocontrol program is under development using the samurai wasp (Trissolcus japonicus), an egg parasitoid.
Widespread implementation of biocontrol requires efficient mass rearing, which is constrained by the availability of fresh BMSB eggs in lab colonies. Samurai wasp is ideally reared on fresh, newly-laid BMSB egg masses, but availability in lab colonies is limited seasonally. Using frozen egg masses for rearing is a potential solution, but lower quality of frozen eggs may have negative impacts on the samurai wasp.
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In this study, I examined the suitability of frozen BMSB eggs for samurai wasp rearing and experimentation. Parasitism rate, developmental time, sex ratio and size were compared between wasps reared on fresh versus frozen, newly laid (<1 d old) versus variably aged (0–3 d old), and frozen egg masses stored up to 4 years.
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This work was completed in Dr. Jana Lee's lab, with help from members of Dr. Nik Wiman's lab.
Floral resources for samurai wasp conservation in the agroecosystem
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The samurai wasp's efficacy as a biocontrol agent depends on its survival in the field. Wasp populations will be better conserved in the agroecosystem if they have plentiful food sources. Little is known about their feeding habits, except that they can feed on floral nectar. This project investigates potential floral resources for the samurai wasp.
Ideally, these food plants will be located close to crops where BMSB infestations are being targeted, and will be economically or ecologically beneficial to growers. We tested marigold, sweet alyssum, and buckwheat in lab longevity assays and nutrient profile bioassays.
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This work is ongoing in Dr. Jana Lee's Lab. The results are being prepared for publication.
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