Impact of Honeybee Pollination on Productivity and Quality of Broccoli Seed under Chitwan Condition

An experiment was conducted in 1999-2000 to study the impact of honeybees on seed production of broccoli under lower sub-tropical terai agro climatic conditions in Chitwan valley of Nepal, using randomized complete block design (RCBD) with four replications and four treatments- Apis cerana pollinated (Acp), Apis mellifera pollinated (Amp), Naturally pollinated (Np) and control (i.e. without insect pollinators). The broccoli cv Calabreses was transplanted on 16 plots at 60 cm x 50 cm spacing, with 24 plants per plot. The study indicated that both A. cerana and A. mellifera significantly increased the percent pollination (siliqua set). A. cerana pollination contributed in 480.11 and 24.21 percent increase in seed set per siliqua over control and Np, where as the percent increase in the seeds set per siliqua caused by A. mellifera pollination were 479.32 and 24.15 over control and Np, respectively. The highest seed yield was obtained from A. mellifera pollination ((425.880 g/plot) followed by A. cerana (417.500 g/plot) and naturally pollinated (332.75 g/plot). The control plot resulted the lowest seed yield (only 13.35 g/plot). Pollination by both bee species in caged plots increased the pod (siliqua) length significantly over control, but not over naturally pollinated plots. A. cerana (3.750 g) and A. mellifera (3.637 g) pollinated seeds had significantly higher seed weight (1000 seed weight) over naturally pollinated seeds (3.207 g). This study demonstrated that bee pollination could significantly improve in both the yield and the quality of seeds in broccoli in Chitwan conditions.J. Inst. Agric. Anim. Sci. 2003 24:85-89