Despites its tolerance to extreme environmental conditions and biotic stresses, cassava has an annual production deficit in Cameroon of more than 31 million tones. This deficit may be due to agronomic constraints, diseases and pests attacks including whitefly (Bemisia tabaci Genn); vector of the African cassava mosaic disease virus. The aim of this study was to determine among five cassava cultivars including three improved cultivars (TMS 92/0326, TMS 96/1414 and 8034) and two local cultivars (Ekobele and Ngon kribi) those that provide resistance to the development of B. tabaci in relation to soil fertilization. The impact of B. tabaci on these cultivars was therefore measured through the severity and incidence of the mosaic disease. The severity and incidence of cassava anthracnose disease (CAD) and cassava bacterial blight (CBB), which are also important diseases of cassava, were assessed. The study was carried out in Bityili village located in Ebolowa region, at three sites namely Mekoto, Minkon Mingon and Tyele. TMS 92/0326 and TMS 96/1414 had higher average number of adult whiteflies and nymphs, this may be due to their abundance and hairy leaf. Soil fertilization had a significant effect on nymphs. Unfertilized plots had the largest number of nymphs compared to those fertilized. Local cultivars Ekobele and Ngon kribi showed a higher severity and incidence of CMD compared to improved cultivars. All cultivars were weakly and similarly affected by bacterial blight. The fertilization had no effect on the severity of the mosaic and the bacterial blight. The severity of the anthracnose was higher on unfertilized cultivars compared to those fertilized. A strong correlation is observed between the severity of the CMD and yield performance.

Participatory varietal selection is a process that is gradually gaining ground in terms of its ability to improve the results of a selection. This work would identify the preferences of its kind on the choice of the variety of rice in Cameroon. The hypothesis states that rice varietal selection in Cameroon is significantly influenced by gender. Data were collected through individual questionnaires and group interviews from 240 producers in the Mbam, North and Northwest. Using inferential statistic and logistic regression, the study showed that gender has no effect on the choice of rice varieties in Cameroon at all the growing stages.