Effects of insect pollination on okra fruit set and yield along selected habitat gradients at Kilombero District, Tanzania

Dissertation

Pollination is the most important ecosystem services for biodiversity of plants on earth. Insect pollinators are playing an indispensable role in the pollination of agricultural crops such as okra (A. esculentus). The main objectives of the study were; to determine the effects of insect pollination on okra (A. esculentus) fruit set rate and yield at Kilombero district, Tanzania. The split plot design was used, where okra plots were arranged in a randomized complete block design (RCBD) with two treatments and three replications from the edges of natural forest and sugarcane plantation. GenStat Discovery Edition 4 and Microsoft Excel 2021 computer software programs were used in the data analysis. Results indicated that the dominant okra insect pollinators were Macrogalea candida, Braunsapis bouyssouri, Borbo borbonica and Apis mellifera. The insect pollinator species abundance, richness and diversity were higher at the edge of natural forest than sugarcane plantation. The okra plants from the edge of natural forest had significantly higher mean numbers of pods per plant and seed weight per 100 seeds than those from sugarcane plantation. Insect pollination had high significant effects on Okra yield (P < 0.05). In addition, there was high significant effects of insect pollination on okra fruit set rate (P < 0.05). The research has concluded that insect pollinators have substantial effects on fruit set rate and yield of food crops such as okra (A. esculentus). In addition, natural habitats are important. Therefore, conservation of insects' friendly habitats such as natural forests is highly recommended to avoid their decline and consequently declining of pollination services.

Tanzania Forest Services Agency (TFSA)