Effects of honeybee (Apis mellifera) pollination on seed set in hybrid sunflower (Helianthus annuus L.)

Abstract

This study was carried out to determine the efficiency of pollination with honeybee (Apis mellifera) on sunflower hybrid seed production under different types of pollination during 2005 and 2006 in Mustafakemalpasa-Bursa, Turkey. Three pollination types (1) in cages with honeybees, (2) hand pollination (in cages) and (3) in cages without honeybees were used in crosses between two male and three female parents in all possible combinations. The experiment factors; pollination types, male parents and female parents were designed in a split-split plot of randomized complete block. Seed set ratios were 98-99% for pollinations in cages with honeybees or by hand as artificial whereas this ratios was reduced to a level of 4-5% by pollination in cages without honeybees in the both experimental years. Pollination in cages without honeybees produced 93-94% less number of filled seeds per head compared with pollinations by hand and in cages with honeybees. In addition, pollinations in cages with honeybees and by hand resulted in higher 100 seed weight compared with pollination in cages without honeybees. Pollination in cages with honeybees and by hand increased seed yield per head by about 206 and 226%, respectively, compared with pollination in cages without honeybees. Results indicated that the use of honeybees for sunflower hybrid seed production improved seed set ratio, 100 seed weight, number of filled seed per head and seed yield per head.