Impact of Hymenoptera on Abelmoschus Esculentus (L.) Moench, 1794 (Malvaceae) Seed Yields at Bilone (Obala, Cameroon)

Abstract

In Bilone (Obala, Cameroon), during the mild raining season (March-June) in 2019 and 2020, the flowers of Abelmoschus esculentus (Malvaceae) were observed for the study of the activities of Hymenoptera and the determination of the impact of these insects on the yields seedlings of this Malvaceae. Treatments included unlimited floral access by all visitors and bagged flowers to avoid all insect pollinators. The results show that on flowers of A. esculentus, 9 species of insects were recorded. The Hymenoptera occupied the first rank with 84.76 % of the visits. These bees prey on the flowers in the morning and evening, with a peak between 09 10 am. His visits correspond to a very good harvest of the nectar and a weak harvest of the pollen. Comparing the yields of free flowers to those of isolated insects, there is an increase in the number of seeds per pod of 20.59 % in 2019 and 20.87 in 2020 and the percentage of normal seeds of 02.38 % in 2019 and 5.28% in 2020 due to Hymenoptera. This improvement in yields is justified by the positive action of these arthropods on the pollination of the flowers they visit. Therefore, conservation of nests and colonies of Hymenoptera close to A. esculentus crop fields should be recommended to improve pod and seed production in the locality.