Harland Patch, Ph.D.

Harland Patch, Ph.D.

  • Assistant Research Professor
549 Ag Sciences & Industries Building
University Park, PA 16802


  • M.S., Virginia Commonwealth University, 1998
  • Ph.D., University of Illinois at Urbana-Champaign, 2005

Academic Interests

pollinator health; pollinator behavior, population genetics; sustainable agriculture; food security; human nutrition

Affiliated Programs

Center for Pollinator Research, Center for Chemical Ecology, Center for Infectious Disease Dynamics

Courses Taught

Pollination Biology (with H. Hines); Concepts and Techniques in Molecular Ecology (with C. Grozinger); Honeybees and Humans (with M. Frazier, C. Grozinger); Professional Development and Critical Thinking (with J. Frazier, C. Grozinger, J. Rasgon); Pollinator Ecology Seminar (with N. Ostiguy); Genes and Behavior Seminar (with C. Grozinger)

Recent Research/Educational Projects

Honey bee health in East Africa- A collaboration between researchers at Penn State's Center for Pollinator Research and the International Centre for Insect Physiology and Ecology (icipe) in Nairobi has found that the bee pest Varroa destructor is having a limited impact on bees in East Africa at this time.   We also found the three of the common US/European honey bee viruses.  The number of viruses present was positively correlated with Varroa levels, but was not correlated with colony size or hygienic behavior. We also found Nosema apis both at the coast and at an inland sight near Uganda.  Bees in the far north of Kenya did not have Varroa, viruses or Nosema.  We found that levels of Varroa were positively correlated with elevation, suggesting that environmental factors may play a role in honey bee host-parasite interactions. Only a small number of pesticides at low concentrations were found.  Based on our findings these factors do not yet appear to be impacting Kenyan bee populations. Thus chemical control for Varroa and Nosema are not necessary for Kenyan bees at this time. This study provides baseline data for future analyses of the possible mechanisms underlying resistance to and the long-term impacts of these factors on African bee populations.  As an extension of this study, in collaboration with South Eastern Kenya University, we have initiated a series of projects that monitor bee health over time and look at management practices as well as other potential stressors.  A primary goal of this work is to connect scientific research and development to beekeepers, farmers and government and NGOs to improve agricultural productivity.

Nutrition-sensitive Agriculture and Pollinators- Pollinators are essential for global nutrition and sustainable food security. Over the past century much development has focused on increasing mere caloric intake of staple crops with micronutrients as a supplement. Because most of our major global food crops benefit from pollinators any nutrition-sensitive agriculture will require figuring pollinators into the equation.   Many pollinator dependent fruits, vegetables, and nuts, provide vitamins, minerals, fats and other micronutrients, and thus pollinators form a crucial line of defense against micronutrient deficiencies in developing countries and in diverse health diets once undernutrition declines.  Furthermore, the productivity of many high value crops grown in the developing world, such as cacao, coffee, and cashews, is strongly tied to pollination services.  Indeed, the amount of animal pollinated crops grown globally has increased significantly in the last fifty years, making both developed- and developing world countries increasingly dependent on pollinator populations for food security and production of economically important crops.

Host Plant Choice and Pollinator Landscapes- Poor nutrition is implicated as one factor contributing to pollinator declines across the global.  With increasing urbanization and agricultural intensification there can be fewer pollen and nectar resources and fewer breeding and nest sites.  In the context of landscape restoration the questions arises as to which plants provide the best nutrition for pollinating species.  But little is known about pollinator nutrition and how host plants are chosen, although there are clear, temporal and spatial patterns to host finding behavior.  Work in this area will help inform restoration projects and illuminate the evolution patterns of plant-pollinator communities.

Pollinators' Garden at the Arboretum at Penn State- To disseminate the results of this research and the research of some 25 other pollination scientists at Penn State as chair of the Center for Pollinator Research's Arboretum Committee I have been involved in creating an unprecedented Pollinators' Garden.  This garden will, once complete, cover nearly two acres and will be dedicated to education, outreach, extension and research.  Unlike other pollinators' gardens the entire collection of plants will be derived from scientific observations and will composed to support the highest diversity of bees, butterflies and moths, flies, beetles, and other pollinators possible.  It will include food gardens, research gardens, gardens for pollinator diversity in many habitats.

Selected Publications

Patch, H. M., Velarde, R. A., Walden, K.O., and H. M. Robertson (2009) A Candidate Pheromone Receptor and Two Odorant Receptors of the Hawkmoth Manduca sexta. Chemical Senses 34(4):305-316.

Grozinger, C.M. Shpigler, H., Cohen, M., Fan, Y., Patch, H. M. and G. Bloch (2010) Brain expression levels of Kruppel homolog 1 are associated with socially regulated behavioral pathways in both honey bees and bumblebee. BMC Evolutionary Biology 10:120. 

 Miao, M., Yang, Z., Huang, Y., Patch, H., Escalante, A., and L. Cui (2012). Plasmodium vivax populations revisited: mitochondrial genomes of temperate strains in Asia. BMC Evolutionary Biology 12:22.

Vaudo, A., Patch H.M., Mortensen D.,  Grozinger C. M., and J. Tooker. (2014) Bumblebees exhibit behavioral patterns in pollen foraging. Arthropod-Plant Interactions  8:273–283

Fuller, Z.L., Nino, E.L., Patch, H.M., Reina, O., Baumgarten, T., Frazier, M., Muli, E., Schuster, S., Miller, W., and C. M. Grozinger. "Genome-wide analysis of signatures of selection in populations of African honey bees (Apis mellifera) using new web-based tools".  (submitted).

Muli*, E., Patch*, H.M., Frazier*, M., Frazier, J., Torto, B., Baumgarten, T., Kilonzo, J., Kilmani, J., Mumoki, F., Masiga, D., Tumlinson, J., and C.M. Grozinger. (2014) Evaluation of the distribution and impacts of parasites, pathogens, and pesticides on honey bee (Apis mellifera) populations in East Africa.   PLOS ONE 9:4.