Insect pollinators of oil palm in Kerala with special reference to African weevil, Elaeidobius kamerunicus Faust

A study on insect pollinators of oil palm was conducted in the oil palm plantations of Plantation Corporation of Kerala, Athirappilly, Kerala during 2009-10. Fifteen insect species were observed to visit the inflorescence of oil palm. Among them, population of the African oil palm weevil, Elaeidobius kamerunicus (Coleoptera: Curculionidae) was found to be most predominant. Maximum number of weevils visited the female flowers between 10.00am. and 2.00pm. and the peak population was observed on the 1st and 2nd day of anthesis, around 12.00 noon. Highly significant positive (r = 0.712**) correlation was observed between population of E. kamerunicus on 1st day of anthesis of female flowers and per cent pollination whereas, it was not significant (r = 0.199) on the 2nd day of anthesis. Adults of E. kamerunicus fed on the pollen grains of oil palm and they completed their entire life cycle on spent male flowers. Their statistical median population was 48, 76, 80 and 35, 56 and 72 on top, middle and bottom portions of male inflorescence during rainy and summer seasons respectively. A specific anise seed like odour (estragole 5,4 allylanisole) attract the weevils towards both male and female inflorescences.