Works on the diversity, frequency and abundance of plant-parasitic nematodes present in the rhizosphere of cocoa agroforests is lacking in Togo, although these informations are essential for establishing effective control methods. The aim of this study was therefore to identify the parasitic nematodes infesting cocoa agroforests in Togo. Soils and roots were sampled in 24 orchards spread over four agroforest types (< 10 years, 10 to 20 years, 21 to 30 years and > 30 years) and three agroecological subzones (Agou peneplain, piedmonts and plains and Plateaux and mountains). The nematodes extracted were identified on the basis of morphological criteria. The study revealed the presence of Meloidogyne, Pratylenchus, Helicotylenchus, Scutellonema and Radopholus genera and microbivorous nematodes (bacterivores and fungivores). In roots, the genera Meloidogyne, Pratylenchus and Helicotylenchus are the most frequent, accounting for 82.46%. In soils, the Meloidogyne genus and microbivorous nematodes were the most frequent, accounting for 72.65%. Finally, the highest nematode infestations were recorded in agroforests of less than 20 years in the piedmonts and plains. The results obtained could serve as a basis for developing effective nematode management strategies for sustainable cocoa production.

The purpose of this study was to characterize the soils subject to gold mining. Data collection consisted of sampling soil from the 0-20 cm layer, in corn fields, under natural vegetation and in gold panning sites (gold-bearing soil and washed gold-bearing soil). A total of 48 composite samples of 1 kg of soil were analyzed at the ITRA Soil Laboratory in Lomé. The results of physicochemical analysis show that the washed gold soils have low contents of organic matter, carbon, nitrogen, calcium and sodium; and are sandy in texture. Washed gold soils have a very low level of fertility. Over the entire study area, the levels of trace metal elements range from 0.01 to 10.24 mg/kg for copper, 0.02 to 4.01 mg/kg for zinc, 0.01 at 5.05 mg/kg for lead and 0 to 1.40 mg/kg for cadmium. The pollution index varies from 0.01 to 0.09 depending on the localities and is less than 1 in all localities. The lowest index is obtained at Kéméni and Kpaza sites, indicating a low accumulation of trace elements on these sites. The sites of its localities are not polluted by the Cu, Zn, Pb, and Cd studied. Gold panning in the Central Region of Togo leads to soil degradation.

An experiment was conducted to evaluate the effect of aeration on the production parameters of red tilapia (Oreochromis sp.). For this purpose, fry of average weight 5 g were stocked at a density of 30 individuals per hapa in three replicates per concrete tank of 2.5m3 capacity and subjected to four treatments T0 (control), T6, T12 and T24 which are respectively 0, 6, 12, and 24 hours of oxygen supply. The fish were fed three times a day for eight weeks with Raanan feed containing 33% crude protein. After this period, the fish were fasted for two days and then six fish from each batch were dissected to assess the effect of aeration on digestive transit. At the end of the trial, the results obtained show that the survival rate was generally around 97% for all batches. The best zootechnical performances were observed in fish of lots T12 and T24 (Feed conversion rate (FCR) = 2.04 and 1.95; Specific growth rate (SGR) = 3.97 and 4.02%/d). In addition, transit was slower in the digestive tract compartments of fish in these two treatments.