The pest spectrum of Sesbania sesban in southern and eastern Africa

Insect damage has been cited as one of the limiting factors for the planting of the nitrogen-fixing legume sesbania, Sesbania sesban (L.) Merrill, which has shown a great promise for improvement of soil fertility in agroforestry systems. So far the pest spectrum of sesbania has been little known in Africa. Therefore, a number of surveys were undertaken with the objective of determining the beneficial and harmful insects associated with sesbania and identifying potential pests of the tree. Over 86 species of herbivorous insects—including some serious crop pests—were recorded on sesbania in eastern and southern Africa. Sesbania also served as a source of food and refuge for over 51 species of beneficial insects, namely natural enemies and pollinator bees. Although several insects attacked sesbania, Mesoplatys ochroptera Stål (Coleoptera: Chrysomelidae) clearly stood out as the most serious pests in terms of its frequency of occurrence and the damage it does. Therefore, it was treated as the “key pest” of sesbania in eastern and southern Africa. This paper attempts to summarise the results of several studies that have quantified the life history, host plants, spatio-temporal distribution and natural enemies of M. ochroptera. A mathematical model, which is likely to contribute to the explanation of population fluctuations of the beetle and to be used as a basis for optimising pest management strategies, is proposed. Recommendations for the management of M. ochroptera such as good nursery practice, prompt weeding and cultivation in the field, and use of resistant accessions are given. Areas for future research are also indicated.

---

• View source