COMPARATIVE STUDY OF POLLINATION METHOD ON BOTTLE GOURD (Lagenaria siceraria L.) YIELD

Abstract

In Bangladesh, bottle gourd (Lagenaria siceraria L.) is the most important vegetable among different kinds of winter vegetables because of its nutritive value and economic return. The present study was designed in the experimental field of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka during December 2016 to May 2017, to determine the effect of different modes of pollination on fruit and seed characters, foraging behavior of major bee pollinators, various insect visitors and their relative abundance. The experiment was laid out in Randomized Complete Block Design (RCBD) with eight (8) replications and three (3) treatments (without bee pollination, hand pollination, and open pollination). A total of 12 insect species were recorded as visitors in bottle gourd ecosystem. Among them, Formica sp. was most abundant followed by Therioaphis trifolii, Apis mellifera, Halictus sp. and Bactrocera. Cucurbitae, but Syrphids were least abundant. The activity of insects was peaked between 8.00am-9.00am followed by 11.00am-12.00pm and 2.00pm-5.00pm. Least activity was recorded at night 8.00pm-9.00pm. The pollen or nectar foragers proportion of Apis mellifera revealed that there was significantly more number of nectar foragers (6.16/m2/10 min) as compared to pollen foragers (5.27/m2/10 min). The pollen foragers were highest during morning (6.75/m2/10 min) whereas the nectar foragers were maximum during noon (6.74/m2/10 min). The highest percentage of fruit set was observed in hand pollination (71.52%) while the lowest in open pollination (60.85%) and without honey bee pollination (45.65%). Misshapen fruit percentage was highest in without honey bee pollination (23.35%) while the lowest in open pollination (21.87%) and hand pollination (15.01%). Significantly lowest percentage of healthy fruits (78.25%) resulted in without honey bee pollination. Similarly the fruit weight (2200.54 g), number of seeds per fruit (185), fruit diameter (60.8 cm), fruit length (89.7 cm) and weight of 1000-seeds (88.3 g) were found maximum in hand pollination among the three form of pollination as compared to open and without bee pollination.