African Journal of Agriculture

ISSN 2375-1134

African Journal of Agriculture ISSN 2375-1134 Vol. 12 (3), pp. 001-012, March, 2025. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research Paper

Investigating the Long-Term Effects of Endosulfan on Enzymatic and Microbial Functions in Two Agricultural Soils from Yaoundé, Cameroon

Michel Amery Defo1,2*, Thomas Njine2, Moise Nola2 and Florence Sidonie Beboua2

1Institut National de la Recherche Scientifique (INRS), Centre Eau Terre, Environnement, de la Couronne, Quebec,
Canada.
2Laboratory of General Biology, Department of Animal Biology and Physiology, Faculty of Science, University of
Yaounde , Yaounde, Cameroon.

Accepted 17 November, 2024

Abstract

Soil samples with different physical and chemical characteristics were taken from two sites, Minkoa-Meyos and Mendong, in Yaounde. These samples were treated with the insecticide endosulfan, using commercially recommended rates (1.5l ha-1), and incubated in the laboratory at 20°C in glass flask for 75 days in order to evaluate their toxic effects on enzyme activities, organic matter content and the availability of phosphorus in the soils studied. The enzyme activities studied included dehydrogenase, β-D glucosidase, acid and alkaline phosphatases. The results showed that, on one hand, endosulfan inhibits dehydrogenase, acid and alkaline phosphatase activities in both soils. β-D Glucosidase activity was inhibited in Mendong soil, but this activity seems not to be affected by endosulfan in Minkoa-Meyos soil. On the other hand, endosulfan appeared to have no measurable effect on the organic carbon content and on the availability of phosphorus in Minkoa-Meyos soil. However, these two functions were inhibited in the Mendong soil. Moreover, significant correlations in the Mendong soil at the highest concentration were obtained between acid phosphatase activity and the available phosphate (P = 0.024; r = 0.821), and between alkaline phosphatase activity and the available phosphate (P = 0.014; r = 0.858).

Key words: Endosulfan, soil microcosm, enzyme and microbial activities, exposition time.