Effect of bee pollination on yield attributes and seed yield of tori (Brassica campestris var. toria).

摘要

An experiment was conducted during rabi 2002-03 in Pusa, Bihar, India, to study the abundance of insect pollinators visiting on toria flowers at different hours of the day from 08.00 to 16.00 h on different dates (22 November 2002-28 December 2002 at weekly intervals) for 5 minutes/m2 area. To investigate the effect of bee pollination on yield attributing characters (siliqua per plant, length of siliqua, seeds per siliqua and 1000-seed weight) and seed yield of toria, 3 treatments (self-pollinated, bee (Apis mellifera)-pollinated and open-pollinated) were taken. Among the insect visitors (Apis dorsata, A. mellifera, A. florea and A. cerana indica), A. florea outnumbered (23.65), followed by A. mellifera (20.15), while A. dorsata population was the lowest (0.09). The maximum mean number of insect visitors (2.60) was observed at 12.00 h, while the minimum (0.26) at 09.00 h. The highest population of insect visitors was recorded between 10.00 and 14.00 h. No insects were observed at 08.00 and 16.00 h. Full-bloom flowers favoured more foraging than flowers of early age or near maturity. The mean number of siliqua per plant, length of one siliqua, number of seeds per siliqua, 1000-seed weight and seed yield in g/plot and q/ha were 88.3, 5.11, 21.7, 3.13, 2117.52 and 11.74, respectively, in OP, which were significantly higher over BP (78.4, 4.96, 19.4, 2.89, 1733.40 and 9.63, respectively) and SP (63.1, 4.41, 15.3, 2.11, 778.32 and 4.24, respectively).