Performance of hymenopteran insects as pollinators of pumpkin in Meghalaya

Abstract

Pumpkin is a major cultivated crop particularly in north eastern states of India that depends on insects for the pollination, as the pollens of these plants are large sized and sticky. In the present study, field and lab experiments were conducted to determine the efficiency of the pollinators of pumpkin based on their diversity, relativeabundance and foraging activity. Total four hymenopteran insect pollinators were observed in field viz., bumble bee, little honey bee, Indian honey bee and Digger bee. On the basis of abundance and relative abundance bumble bee was identified as most abundant pollinator of pumpkin with 69.69 per cent mean relative abundance as other pollinators mean relative abundance was less than 25 per cent and it was only 3.49 per cent for Indian honey bee. Foraging speed and foraging rate of bumble bee was 7.13 sec/flower and foraging rate was 3.80 flower/minute. To ensure the efficient pollinator of pumpkin flower, pollen carrying capacity, pollen deposition and percent deposition of viable pollen was studied for all the pollinators in field and laboratory condition. The pollen carrying capacity of pollinators ranged from more than 7 mg to 1 mg. It was highest for bumble bee which was 7.33 mg followed by little honey bee (6.66 mg) and least pollen carrying capacity was observed in Digger bee (1.67 mg). Pollen depositions by pollinators on stigma in a single visit was again highest for bumble bee (565 pollen grains) with maximum number of viable pollen deposition 224.33 pollen grains out of which 39.7 per cent pollen was viable. So on the basis of above result it can be concluded that bumble bee was the most abundant and most efficient pollinator of pumpkin.

Diversity and Abundance of Insect Pollinators of Cucurbits at Mid-Hills of Meghalaya, India

“…Bumble bee was observed from teasel gourd and one unidentified native bee was also collected. Similar findings were also observed by other researchers in different cucurbits and other crops (Atwal, 1970;Devi et al, 2014;Hemanth Kumar, 2006;Mandelika and Roll, 2009;Pande et al, 2015a;Pande et al, 2017;Pande et al, 2021;Pande et al, 2023;Prakash, 2002).…”

Impact of the “Farming With Alternative Pollinators” Approach on Crop Pollinator Pollen Diet

“…Pumpkin provides abundant nectar rewards and displays accessible flowers (Vidal et al, 2006). Through the showy open flowers and the large amount of nectar, pumpkin attracts a wide array of flower visitors (Burgett, 2000), including pollinators with wide dietary breadth (Nicodemo et al, 2009;Artz and Nault, 2011;Ali et al, 2014;Pande and Verma, 2016). The important proportion of species with wide dietary breadth visiting pumpkin and faba bean underline the importance of providing diverse flowering plants to conserve healthy crop pollinators and other pollinators living in this area or farm.…”

“…For instance, pollen of Cucurbitaceae (e.g., zucchini and melon) is sticky, large, heavy, and contains many chemical compounds that discourage bees from its consumption (Lundgren, 2009;Rodrigo Gómez et al, 2016;Brochu et al, 2020). However, the high amount of nectar they produce attracts a wide array of flower visitor species (Ali et al, 2014;Pande and Verma, 2016). Cultivated and wild lupinus are nectarless and are mainly visited for pollen (McGregor, 1976).…”