The omics approach to bee nutritional landscape.

Malnutrition is one among several causative factors for global bee pollinator declines. Given the importance of nutrition, it is imperative to understand bee nutrition holistically, identifying dietary sources that may fulfill bee nutritional needs. Targeted sterol analysis and untargeted metabolomics were conducted on commercially-pollinated crop pollens, bee-collected crop pollens, three vegetable oils (often added to artificial protein supplements by beekeepers), and one commonly used artificial protein supplement.

Chakrabarti, P., Morre, J.T., Maier, CS. and Sagili, R.R. (2019) The Omics Approach to Bee Nutritional Landscape. Metabolomics 15:127.

Assessment of Pollen Diversity Available to Honey Bees

Many cropping systems that employ honey bee colonies for pollination may lack sufficient pollen diversity and abundance to provide optimal bee nutrition. In this observational study, we documented the diversity and relative abundance of pollen collected by honey bees in five major pollinator-dependent crops in the western United States.

Topitzhofer, E., Lucas, H.M., Chakrabarti, P., Breece, C., Bryant, V. and Sagili, RR. (2019) Horticulture Assessment of pollen diversity available to honey bees (Hymenoptera: Apidae) in major cropping systems during pollination in the western United States. Journal of Economic Entomology 1-9.

Honey bees consider larval nutritional status when selecting larvae for emergency queen rearing

Larval nutritional state is meticulously assessed and used by workers in selection of larvae for queen rearing. We conducted a series of experiments manipulating the nutritional status of one day old larvae to test this. Our results demonstrate that honey bees perceive the nutritional state of larvae and use that information when selecting larvae for rearing queens in the natural emergency queen replacement process.

Sagili, R.R., Metz, B.C., Lucas, H.M., Chakrabarti, P. and Breece, C.R. (2018) Honey bees consider larval nutritional status rather than genetic relatedness when selecting larvae for emergency queen rearing. Scientific Reports 8, 7679

Establishment of the pesticide intensification gradient in Eastern India

Extensive farmer surveys for the quantity and frequency of pesticide use was conducted along with landuse mapping of the sites. Pesticide residues were analyzed from soil samples and honey bee tissues to further help us establish the gradient. Based on all the extensive research, the field sites for pesticide intensive agricultural landscapes were chosen in two Eastern Indian states. One was located in the state of West Bengal and the other in the state of Odisha.

Chakrabarti, P. Rana, S, Smith, B, Sarkar, S. and Basu, P. (2015) Pesticide induced oxidative stress in laboratory and field populations of native honey bees along intensive agricultural landscapes in two Eastern Indian states. Apidologie 46(0,107 -129

Pesticide induced visual abnormalities in Asian honey bees

The present study investigates the visual acuity of honey bees exposed to pesticides. Even though overall morphometric examinations revealed no significant differences between the populations with respect to overall eye size, correct color choices by bees in pesticide exposed populations were significantly reduced, along with a significant reduction in ommatidia facet diameter and a significant reduction in expression of two visual proteins – blue-sensitive opsin and rhodopsin.

Chakrabarti, P. Sarkar, S. and Basu, P. (2019) Pesticide induced visual abnormalities in Asian honey bees (Apis cerana L) in intensive agricultural landscapes. Chemosphere 230, 51 – 58.

Pesticide induced olfactory impairments in Asian honey bees

This particular study highlights the detrimental effects of pesticides on honey bee olfaction through behavioural studies (proboscis extension responses), scanning electron microscopic imaging of antenna! sensilla, expression of Calpain 1 (an important calcium binding protein) and confocal microscopic studies of honey bee brains for calcium ions in Apis cerana.

Chakrabarti, P, Rana, S, Bandopadhyay, S, Naik, D.G, Sarkar, S. and Basu, P. (2015) Field populations of native Indian honey bees from pesticide intensive agricultural landscape show signs of impaired olfaction. Scientific Reports 5, 12504.

Pesticide-induced oxidative stress in Asian honey bees

This study looked into the effect of pesticides with respect to oxidative stress in the laboratory and in field populations of two native Indian honey bee species (Apis dorsata and A. cerana) by examining a combination of biomarkers, e.g., superoxide dismutase, catalase and xanthine oxidase.

Chakrabarti, P., Rana, S., Smith, B., Sarkar, S. and Basu, P. (2015) Pesticide induced oxidative stress in laboratory and field populations of native honey bees along intensive agricultural landscapes in two Eastern Indian states. Apidologie 46(1),107 -129.

Collating and validating indigenous and local knowledge to apply multiple knowledge systems to an environmental challenge:

There is an important role for indigenous and local knowledge in a Multiple Evidence Base to make decisions about the use of biodiversity and its management A novel method, to gather evidence in which a peer-to-peer validation process has been used among farmers, is analogous to scientific peer review.

Smith, B.M., Chakrabarti, P., Chatterjee, A., Chatterjee, S., Dey, U.K., Dicks, L.V., Giri, B., Laha, S., Majhi, R.K. and Basu, P. (2017) Collating and validating indigenous and local knowledge to apply multiple knowledge systems to an environmental challenge: A case-study of pollinators in India. Biological Conservation 211(A), 20

Pesticide induced altered genetic diversity in Asian honey bees

The study reports an increased genetic diversity in native Apis cerana populations continually exposed to pesticide stress. This study reports such changes for the first time in native wild Indian honey bee populations exposed to pesticides and has far-reaching implications on the population adaptability under pesticide stress. Methods used RAPD-PCR and isozyme studies.

Chakrabarti, P., Sarkar, S. and Basu, P. (2018) Field Populations of Wild Apis cerana Honey Bees Exhibit Increased Genetic Diversity Under Pesticide Stress Along an Agricultural Intensification Gradient in Eastern India. Journal of Insect Science 18 (3):1 -0.