Thanu, C N
Diversity and ecology of the blue banded bees, Amegilla spp (Hymenoptera:Apidae) - Vellanikkara Department of Agricultural Entomology, College of Agriculture 2023 - 83,xip.
MSc
Insects play a crucial role in pollination with around 75 per cent of crop plants relying on insects, especially bees. However, due to the prevalent use of managed bee pollinators, the significance of wild pollinator’s service in agriculture is often unnoticed. Wild bees play a crucial role in delivering essential pollination services to wild plants and crops in agricultural ecosystems. Among wild bees, the blue banded bees, Amegilla spp. have been identified as an effective pollinator of various horticultural crops such as capsicum, tomato, and brinjal. In Kerala, studies on the blue banded bees are scanty. Therefore, this study was undertaken to explore the diversity, palynology, nesting architecture and behaviour of blue banded bees.
Purposive surveys were conducted to collect the blue banded bees in central and northern districts of Kerala viz., Thrissur and Wayanad, respectively. Morphological and molecular characterization of the collected specimens revealed nine species of blue banded bees namely, Amegilla calceifera, A. zonata, A. cingulata, A. cingulifera, A. dizona, Amegilla (Zonamegilla) sp., Amegilla sp.1, Amegilla sp.2, and Amegilla sp.3.
Palynological studies of pollen loads collected from Thrissur and Wayanad districts revealed the presence of 12 pollen types under eight plant families and eight pollen types under six plant families, respectively. Floral hosts of the family Fabaceae were the most preferred pollen source for the blue banded bees in both the districts. Melastoma malabathricum, Solanum melongena, and Ocimum sp. were the predominant pollen types in Thrissur and Mimosa pudica was the predominant pollen type in Wayanad.
Natural nesting locations of blue banded bees were identified in inaccessible places. Female bees were found digging soil under stones, near shaded areas and at the base of buildings in search of suitable nesting sites. Blue banded bees did not form nests in the artificial nesting sites provided with various nesting substrates viz., red soil, laterite soil, potting mixture and clay soil.
During summer months, foraging bout started at around 6.15 am and continued until 6.35 pm. The peak foraging activity of bees was observed from 10.00 to 11.00 am. In partly cloudy to sunny weather, foraging was observed when the temperature ranged between 280C and 350C. However, the foraging period ranged between 6.50 am and 6.10 pm during the rainy season.
The number of bees visited on Asystasia gangetica from 10.00 to 11.00 am was significantly higher (15.38) than all other hosts on all different timings and the lowest was on M. malabathricum (1.74) from 4.00 to 5.00 pm. The number of flowers visited by the bees were statistically highest (28.16) on Duranta plumieri from 10.00 to 11.00 am and the least number of visits was on M. malabathricum from 4.00 to 5.00 pm (4.64). Significantly more time per flower spent by the bees on M. malabathricum (12.01 sec) between 10.00 to 11.00 am and the minimum time was spent on D. plumieri flowers from 2.00 to 3.00 pm as well as 4.00 to 5.00 pm.
Fourty six host plants under 25 different families were identified as the floral resources for blue banded bees. They preferred to forage mostly on the plant species of family Lamiaceae, Verbenaceae, Acanthaceae, Rubiaceae and Bignonaceae; bees were found attracted more to white flowers, followed by purple-coloured flowers.
Male biased and intraspecific sleeping cluster of A. zonata was found on the dried twig of Alternanthera sp. in Thrissur. Isolated roosting of A. zonata female was also seen on the dried stem of Panicum sp. In Wayanad, two male biased and interspecific sleeping clusters composed of two species viz., A. zonata and A. calceifera were found on Emilia sonchifolia. The time of sleeping cluster formation was between 6.12 to 6.58 pm and the departure time in the morning was between 6.02 am and 6.25 am. The number of bees forming the cluster varied every day.
Understanding the mutualistic relation between crops and pollinator species is essential. Their spatial and temporal fluctuations, foraging habits and effectiveness in pollination are the factors influencing the success of pollination. Currently, there is very less studies regarding the involvement of wild pollinators in the pollination of crops. The genus Amegilla serves as an example, highlighting the presence of potential pollinators of agricultural crops. Additional research to explore the potential of Amegilla as a viable and significant pollinator within agricultural systems is crucial.
Agricultural Entomology
Blue banded bees
Amegilla spp
Hymenoptera:Apidae
632.6 / THA/DI PG
Diversity and ecology of the blue banded bees, Amegilla spp (Hymenoptera:Apidae) - Vellanikkara Department of Agricultural Entomology, College of Agriculture 2023 - 83,xip.
MSc
Insects play a crucial role in pollination with around 75 per cent of crop plants relying on insects, especially bees. However, due to the prevalent use of managed bee pollinators, the significance of wild pollinator’s service in agriculture is often unnoticed. Wild bees play a crucial role in delivering essential pollination services to wild plants and crops in agricultural ecosystems. Among wild bees, the blue banded bees, Amegilla spp. have been identified as an effective pollinator of various horticultural crops such as capsicum, tomato, and brinjal. In Kerala, studies on the blue banded bees are scanty. Therefore, this study was undertaken to explore the diversity, palynology, nesting architecture and behaviour of blue banded bees.
Purposive surveys were conducted to collect the blue banded bees in central and northern districts of Kerala viz., Thrissur and Wayanad, respectively. Morphological and molecular characterization of the collected specimens revealed nine species of blue banded bees namely, Amegilla calceifera, A. zonata, A. cingulata, A. cingulifera, A. dizona, Amegilla (Zonamegilla) sp., Amegilla sp.1, Amegilla sp.2, and Amegilla sp.3.
Palynological studies of pollen loads collected from Thrissur and Wayanad districts revealed the presence of 12 pollen types under eight plant families and eight pollen types under six plant families, respectively. Floral hosts of the family Fabaceae were the most preferred pollen source for the blue banded bees in both the districts. Melastoma malabathricum, Solanum melongena, and Ocimum sp. were the predominant pollen types in Thrissur and Mimosa pudica was the predominant pollen type in Wayanad.
Natural nesting locations of blue banded bees were identified in inaccessible places. Female bees were found digging soil under stones, near shaded areas and at the base of buildings in search of suitable nesting sites. Blue banded bees did not form nests in the artificial nesting sites provided with various nesting substrates viz., red soil, laterite soil, potting mixture and clay soil.
During summer months, foraging bout started at around 6.15 am and continued until 6.35 pm. The peak foraging activity of bees was observed from 10.00 to 11.00 am. In partly cloudy to sunny weather, foraging was observed when the temperature ranged between 280C and 350C. However, the foraging period ranged between 6.50 am and 6.10 pm during the rainy season.
The number of bees visited on Asystasia gangetica from 10.00 to 11.00 am was significantly higher (15.38) than all other hosts on all different timings and the lowest was on M. malabathricum (1.74) from 4.00 to 5.00 pm. The number of flowers visited by the bees were statistically highest (28.16) on Duranta plumieri from 10.00 to 11.00 am and the least number of visits was on M. malabathricum from 4.00 to 5.00 pm (4.64). Significantly more time per flower spent by the bees on M. malabathricum (12.01 sec) between 10.00 to 11.00 am and the minimum time was spent on D. plumieri flowers from 2.00 to 3.00 pm as well as 4.00 to 5.00 pm.
Fourty six host plants under 25 different families were identified as the floral resources for blue banded bees. They preferred to forage mostly on the plant species of family Lamiaceae, Verbenaceae, Acanthaceae, Rubiaceae and Bignonaceae; bees were found attracted more to white flowers, followed by purple-coloured flowers.
Male biased and intraspecific sleeping cluster of A. zonata was found on the dried twig of Alternanthera sp. in Thrissur. Isolated roosting of A. zonata female was also seen on the dried stem of Panicum sp. In Wayanad, two male biased and interspecific sleeping clusters composed of two species viz., A. zonata and A. calceifera were found on Emilia sonchifolia. The time of sleeping cluster formation was between 6.12 to 6.58 pm and the departure time in the morning was between 6.02 am and 6.25 am. The number of bees forming the cluster varied every day.
Understanding the mutualistic relation between crops and pollinator species is essential. Their spatial and temporal fluctuations, foraging habits and effectiveness in pollination are the factors influencing the success of pollination. Currently, there is very less studies regarding the involvement of wild pollinators in the pollination of crops. The genus Amegilla serves as an example, highlighting the presence of potential pollinators of agricultural crops. Additional research to explore the potential of Amegilla as a viable and significant pollinator within agricultural systems is crucial.
Agricultural Entomology
Blue banded bees
Amegilla spp
Hymenoptera:Apidae
632.6 / THA/DI PG