Agents of Pollination on Fruit Set of Piper nigrum L.

The role of agents on pollination and fruit set of Piper nigrum L. was carried out in the Department of Plantation Crops and Spices, College of Agriculture, Vellayani, Thiruvantha puram during 2017-2019. The role of wind, gravity, rain and dew were investigated and the data was analyzed on twenty-five inflorescences of field grown black pepper plants and twenty-five inflorescences of pot grown bush pepper plants. The fruit set was superior due to the influence of wind and gravity (95.99%) in pot grown bush pepper and it was 91.98 per cent in field grown black pepper vines. The percentage of fruit set due to wind in field grown black pepper and potted bush pepper was 77.67% and 59.39 % respectively. The role of rain water in the pollination also revealed higher fruit set of 92.76% under natural conditions. Insects which visited black pepper spike were foraging nectar and common visitors were yellow crazy ant, black garden ant and pollu beetle with visit rates of 1.79, 1.41 and 0.45 respectively. The small size of pollen with high pollen availability makes it suitable to be carried away by wind. The pendulous nature of the spike, the shedding of pollen, the pollen carried by the rainwater or dew down the spike can all contributed to pollination. Integration of more factors resulted in more fruit set. Characteristics of black pepper flowers studied revealed their adaptation for wind pollination and the pendulous nature of the spike makes it efficient to carry the pollen due to gravity as well as rain and dew for pollination. The role of insects in pollination in black pepper was precluded.