90e8dc4e-e9ea-4bd1-8d1c-cadeaaae2b64I am a PhD Candidate in the Graduate Group in Ecology studying  flower visitor networks and floral microbes.

Here’s a link to my Curriculum Vitae , and you can read more about my research below.

PGPs: he/him/his or they/them/theirs – what are PGPs?

email: kazemenick [at] ucdavis [dot] edu

twitter: @mtn_ash

bugguide: AshZem

 

 


Overview:

Floral nectar is an important resource for pollinators and other animals including beneficial insects (e.g. parasitic wasps and predatory insects). Bacteria and yeast also flourish in floral nectar, and can drastically change the chemical profile of nectar and pollinator visitation rates. However, its unknown how opportunistic (non-pollinating) flower visitors like parasitic and predatory insects interact with nectar-inhabiting microbes.  The goal of my research is to learn how pollinating and non-pollinating insects influence, and are influenced by, nectar microbe communities. My hope is that learning more about these interactions can inform management of agroecosystems to sustain pollination and pest control services.


My Research:

I use observational and experimental field methods & already-existing flower visitor datasets to evaluate:

1) how opportunistic (non-pollinating) flower visitors affect flower visitor network structure

2) whether opportunistic flower visitors disperse nectar microbes

3) how promiscuous (hub) plant species affect the diversity and dispersal of floral microbes in plant communities


Nectar microbes & flower visitors of cultivated strawberries

I am using cultivated strawberries to assess whether non-pollinating flower visitors disperse nectar microbes, and whether nectar microbes affect the preference and performance of pollinating and non-pollinating flower visitors.

So far I’ve observed many types of flower visitors including: honeybees, solitary bees, syrphid flies, other flies, parasitoid wasps, big-eyed bugs, minute pirate bugs, aphids, argentine ants, and butterflies.

I’ve also found various types of bacteria and yeast in strawberry floral nectar.

Click here to check out a fact sheet I’ve made on beneficial insects in strawberry farms.

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Left: an aphid feeding on strawberry nectar, Middle: yeast cultured from strawberry nectar, Right: a nectar-eating Geocoris


Floral microbes in the context of flower visitor networks

With the help of four awesome interns (pictured below), I am constructing a quantitative flower visitor – plant – floral microbe network. Combined with manipulative experiments on a focal plant species (Aquilegia formosa), I hope to explore how ge plants (that receive visits from a high diversity of  foragers) influence the diversity and distribution of floral microbes in the plant community. The study site is a high elevation (~8,000ft) wet meadow nested in virgin forest in Tahoe National Forest in the Sierra Nevada.

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2015 Field Crew [Sam Rusoff, Some Goofball, Alex Sinclair, Ann Le, and Philip Campos]


Collaborators

Rachel Vannette, University of California, Davis

Tadashi Fukami, Stanford University


Publications:

Jackson, D., A.T. Zemenick, B. Malloure, C.A. Quandt, and T.Y. James. 2016. Fine-scale spatial genetic structure of a fungal parasite of coffee scale insects. Journal of Invertebrate Pathology 139: 34-41. PDF

MacDonald, A.J., D. Jackson, and K.A. Zemenick. 2013. Indirect effects of a fungal entomopathogen, Lecanicillium lecanii (Hypocreales: Clavicipitaceae), on a coffee agroecosystem ant community. Environmental Entomology 42(4): 658-667. PDF

Jackson, D., K.A. Zemenick, and G. Huerta. 2012. Occurrence in the soil and dispersal of Lecanicillium lecanii, a fungal pathogen of the green coffee scale (Coccus viridis) and coffee rust fungus (Hemileia vastatrix). Tropical and Subtropical Agroecosystems 15: 389-401. PDF


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my happy place & primary field site