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Species of the Khaya genus are subject to overexploitation for timber and medicinal uses, leading to the threat of their extinction. This study on the spatial distribution and demographic structure of species of the Khaya genus was carried out on the Atakora range in Togo. Its general objective is to contribute to the sustainable management of Khaya spp. in Togo. It specifically aims to: determine the spatial distribution of species of the Khaya genus on the Atakora range in Togo and analyze the impact of anthropogenic pressure on their demographic structure. The methodology used is based on forest inventory by sampling oriented by the presence of Khaya spp. inside 154 plots of 2500 m² in fields and fallows, 900 m² in wooded savannahs, 400 m² in open forests and agroforests and 500 m² in gallery forests. The dendrometric parameters recorded are: the total height and diameter of all woody species from the measurement of their circumferences. Khaya spp. identified in the study area are: Khaya senegalensis, Khaya grandifoliola and Khaya anthotheca. The density of Khaya spp. is variable across the entire Atakora range. It is higher in the southern part of ecological zone II and in the southwestern part of ecological zone IV where this density is greater than 50 plants/ha. This density is higher in light forests and in agroforests. The demographic structure of Khaya spp. is bell-shaped with a predominance of small diameter individuals. Older individuals with large diameters are more often harvested for timber. The regeneration of K. senegalensis is higher than that of K. grandifoliola and K. anthotheca. The plants of K. senegalensis are more cut in the study area and also most of the plants of this species have reached maturity releasing the seeds for regeneration. Species of the Khaya genus are heavily exploited in Togo, hence the need to adopt sustainable management methods such as intensive reforestation and the application of good organ harvesting methods for the survival of these species.

The study focuses on the analysis of practices, attitudes and knowledge of gardening in relation to of pesticides use in Togo. It covered the five (5) administrative regions of the country by a structured survey of 297 gardeners. 98 % of them agree that the use of pesticides reduces losses due to pests and ensure good performance. However, the decision to perform pesticide treatments and the times of treatment differs from one gardener to another and from one region to another. Use patterns and deficiency periods are not under control. Gardeners mostly poorly trained (14 %) do not have a good knowledge of application rates and frequencies of treatment. They are less convinced by direct risks they face and thereby rarely protect themselves.