Cassava mosaic disease and its whitefly vector in Cameroon: Incidence, severity and whitefly numbers from field surveys.

Cassava plays a key role in the food security and economy of Cameroon, but its production is constrained by cassava mosaic disease (CMD). However, comprehensive surveys of CMD in Cameroon have been lacking. This study aimed at evaluating the current status of CMD and its whitefly vector. Field surveys were conducted in 2020 using a sampling, diagnostics and data storage protocol that has been harmonized across 10 West and Central African countries for ease of comparison. Thirty plants per field were assessed for CMD severity, whitefly abundance and source of infection. Surveys were conducted in 343 fields and confirmed the presence of CMD in all 10 regions of Cameroon. Among the 10,057 assessed plants, 33.07% were deemed healthy (asymptomatic). At the field level, only 6.7% fields were found to be healthy. The mean CMD incidence across the country was 66.93%, and the mean severity score was 2.28. The main mode of infection was likely through contaminated cuttings. The mean whitefly count per plant was 5.78. This study is the first countrywide survey of CMD in Cameroon and provides insights that can be useful for improving the country's CMD intervention and management strategies.

Antidiabetic activity of the aqueous extract of Erigeron floribundus leaves in streptozotocin-induced type 1 diabetes model in Wistar rats.

Backgroud: Erigeron floribundus is a herbaceous plant used in traditional Cameroonian medicine to treat diabetes mellitus. The aim of this study was to evaluate the antidiabetic properties of the aqueous extract of E. floribundus leaves (AEEF) in diabetic rats. Methods: Diabetes was induced by a single intraperitoneal injection of streptozotocin (60 mg/kg) in normal rats fasted for 16 h. Subsequently, 30 diabetic male rats were divided into groups and treated orally for 21 days with distilled water (10 mL/kg), glibenclamide (3 mg/kg) and AEEF (300, 400, and 500 mg/kg). Body weight, food and water intake, blood glucose, insulin levels, lipid and oxidative profiles, as well as some markers of liver and kidney function were assessed. Histological sections of the rats' pancreas were taken. Results: AEEF and glibenclamide significantly increased (p < 0.001) body weight and decreased food and water intake in rats. A decrease in blood glucose (p < 0.001) and an increase in insulin levels (p < 0.001) were observed in the AEEF and glibenclamide groups. AEEF caused a significant (p < 0.001) decrease in the levels of total cholesterol, LDL-c, triglycérides and coronary risk index (CRI), accompanied by a significant (p < 0.001) increase in HDL levels and HOMA-ß in rats. AEEF showed an improvement (p < 0.001) in CAT and SOD activity and GSH levels accompanied by a significant decrease (p < 0.001) in malondialdehyde levels. In addition, ALAT and ASAT activity, urea and creatinine levels were significantly reduced (p < 0.001) after treatment with AEEF and glibenclamide. The extract also improved the size of Langerhans Islets in the pancreas of diabetic rats. Conclusion: AEEF contains several bioactive compounds conferring antidiabetic, anti-dyslipidemic and antioxidant properties, thus justifying its therapeutic use in the treatment of diabetes mellitus.