Studies on Diversity and Abundance of Insect Pollinators in Coriander (Coriandrum Sativum L.) and Black Cumin (Nigella Sativa L.) Growing Areas of New Gangetic Alluvium of West Bengal, India

Among the seed spices coriander (Coriandrum sativum L.) and back cumin (Nigella sativa L.) are the dominant seed spices which possess potential export market.Understanding the abundance and diversity of insect fauna that are actively involved in cross pollination is crucial for the production of higher quality seed yield.During the study period (rabi season 2018-19 to 2019-20) total 25 insects belonging to 13 genera were observed in coriander growing areas.Further, order Hymenoptera comprised of (86.38%) abundance among all insect visitors in Hoogly when compared to North 24 parganas (67.48%) and Nadia (70.71%) and Shannon diversity indices of insect visitors in New Gangetic alluvial areas was (2.20), evenness (0.68) and richness was about (3.22) during survey.During black cumin blooming period a total of 15 insects belonging to 12 genera were observed.Further order Hymenoptera comprised of (90.96%) abundance among all insect visitors in Hoogly when compared with Nadia (87.98 %) and diversity indices of New gangetic alluvial zone was (1.81) which indicates insect visitors are moderately diversified and J value or evenness within the 4 orders of insect visitors being more in Hoogly district (0.74) as compared to Nadia during survey.