MSc

The present investigation on “Melissopalynology of Indian honey bee (Apis cerana indica Fab.) apiaries in southern Kerala” was conducted at Department of Entomology, College of Agriculture, Vellayani during 2012-2013. The objectives were to study the potential pollen and nectar sources of Indian honey bee across the seasons in southern Kerala. Fifteen apiaries with a minimum of ten hives were selected purposively from midland and upland physiographic regions of Thiruvananthapuram and Kollam districts. Three samples each of honey and pollen load was collected randomly from the selected apiaries at three seasons viz. honey flow season (January to April), dearth season (June to September) and brood rearing season (October to December). The collected samples were analyzed in the laboratory and the pollen types were identified and quantified.

Mean pollen density of honey samples were found significantly different between the seasons, locations and locations within the seasons. Maximum mean pollen density was recorded in brood rearing season followed by honey flow season and dearth season. Among the locations, Pathanapuram of midland physiographic region had maximum mean pollen density while Veliyam recorded lowest mean pollen density.

A total of 69 plants were recorded as foraging plants by bees from the study area (15 locations) over the three seasons. Twenty four pollen types were identified up to species level, four up to genus level and twenty nine up to family level. Twelve pollen types were unidentified. Identified plant species were Cocos nucifera, Mimosa pudica, Accacia auriculiformis, Mimosa invisa, Spilanthes calva, Elaeis guineensis, Cullenia exarillata, Tagetes erecta, Tridax procumbens, Hibiscus rosasinensis, Dillenia pentagyna, Hopea ponga, Bombax sp., Schleichera oleosa, Rosa sp., Tabernaemontana gamblei, Trichilia connaroides, Mangifera indica, Microtropis stocksii, Peltophorum pterocarpum, Poeciloneuron paucifolium, Psidium guajava, Terminalia paniculata, Impatiens sp., Borassus flabellifer, Passiflora foetida and Colocasia esculenta.


Pollen spectra revealed that though the percentage of pollen types varied among the samples of various locations, maximum contribution throughout the season was made by M. pudica and C. nucifera.

Seasonal occurrence of pollen types revealed that maximum number of pollen types obtained during honey flow season (46 nos.) followed by brood rearing season (33 nos.) and dearth season (26 nos.). Nine pollen types (C. nucifera, M. pudica, A. auriculiformis, M. invisa, and plants belonging to families Oleaceae, Fabaceae, Anacardiaceae, Elaecarpaceae and Myrtaceae) were commonly seen during all the seasons. Of these 9 types, C. nucifera and M. pudica were the predominant (>45 %) as well as the frequently occurring pollen types during all the three seasons. Fifteen locations were grouped into four clusters based on the presence or absence of 69 pollen types.

Thus, the palynological investigation of honey and pollen samples collected from Indian bee apiaries of Thiruvananthapuram and Kollam districts revealed the presence of 69 different foraging plants for their colonial sustenance and honey production.