To evaluate the impact of insect pollinators on pod, seeds, and seed yields of Allium cepa, the pollinating activities of flowering insects were studied in Maroua, during two dry seasons in 2017 and 2018 (November-April). Observations were made on 40120 flowers per treatment. The flowers were subjected to different treatments: Treatment 1 (Free flowers); treatment 2 (bagged flowers); treatment 3 (castrated and free flowers); and treatment 4 (castrated and bagged flowers). About 320 flowers of A. cepa (Liliaceae) were observed in 2017 and 2018, respectively, for the diversity and frequency of insects visits. For results, 6581 visits of 32 insect species distributed in seven orders were recorded on A. cepa flowers. The most dominating Hymenoptera observed was Apis mellifera followed by Lipotriches collaris with 24.49% and 12.43% of the total insect visits, respectively. The highest number of insect pollinators harvested in the flowers of this Liliaceae was between 8 and 9 h. The studied insects have a positive impact on the yields of this plant. This positive impact of the pollinator insects on the yields was 81.09%, 87.79%, and 96.54% in fructification rate, number of seeds pod, and percentage of normal seeds, respectively. The avoidance of pesticide treatment of plants during flowering could be a good management strategy to improve on plant yield.
Key words: Keywords: Allium cepa, flowers, insects, pollination, yield
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