Abstract

Prior to commencement of this study, a survey to identify common bees pollinating C. Arabica in Kenya was done. Patellapis zonalictus, Apis mellifera and Lasioglossum spp. were identified as the common pollinators of C. arabica flowers. Pollination efficiency was analyzed indirectly by assessing pollen deposition on stigmas. Flowers were bagged at bud stage. When the pollinator exclusion bags were removed, the virgin flowers were allowed a single pollinator visit and then the stigmas crushed on a microscope slide and stained using fuchsin dye. The pollen grains deposited on the stigma were counted under a dissecting microscope. The numbers of non coffee pollen grains were also counted to assess pollen purity. Results indicated that P. zonalictus and Lasioglossum spp. were more efficient pollinators of C. Arabica than A. mellifera. They deposited significantly higher amounts of C. Arabica pollen grains. The pollen grains also had a significantly higher purity ratio when compared with the pollen grains deposited by Apis mellifera (p<0.001).

Keywords:

Coffea Arabica, pollen deposition, pollen purity, pollinator efficiency, stigma,

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