Stored seeds of Phaseolus vulgaris L. in are the target of several insects like Acanthoscelides obtectus Say. These pests can cause losses greater than 80 % after six to seven months of storage. The present study aimed to evaluate the insecticidal effects of Moringa oleifera seeds on adults of A. obtectus in storage through two compositions (ie powdery and oily). Four concentrations of oils (3.33; 6.66; 9.99 and 13.33 μl/g), four powder concentrations (4; 16.67; 33.33 and 50 %) and one negative control (C0 = 0 μL / mL) for each composition were used. The experiment was conducted in the laboratory, with four repetitions. The results of the oil contact toxicity test revealed 100 % mortality at doses of 300 and 400 μL after two days of exposure. As for Moringa powder, the insecticidal effect was less pronounced for all doses with a mortality rate of 55 % at day 5 for doses 10 and 15 g. The inhibition of eggs laid and their viability is a function of the concentration of Moringa oil. On the other hand, the powder had no effect on the number of eggs laid and rather stimulated the viability of the eggs. Moringa oil prevents weight loss of stored bean seeds with a null loss percentage at doses of 300 and 400 μL. As for the powder, it had no effect on the weight loss of bean seeds in storage. The powder and oil of Moringa seeds did not affect the germination capacity of the seeds for all the doses tested. Moringa seed oil can therefore be exploited in the integrated control of the pest of common bean seeds in storage.

The present study characterized the plant diversity of oil palm plantations in function of farming practices and their ages. The plant diversity of 7, 11 and 14 years old oil palm plantations evolving in different farming practices was inventoried using 1m x 1m quadrats for herbaceous species and the 20 m wide transects for woody species. The results obtained show that these stands are not very diversified: P7 presents 37 species, 34 genera and 27 families; P11, 27 species 26 genera, 18 families and P14, 31 species, 28 genera, 19 families. Only Ng13 had woody species individualized into trees and shrubs. The combination of manual and chemical weeding and irregular fertilization promotes the diversity of herbaceous species in the different stands. Age and farming practices influence the plant diversity of the stands.