Cowpea, Vigna unguiculata (L.) Walp. (Fabaceae) is a legume that plays an important role in the dietary balance of tropical populations. These seeds are an important source of protein that can make up for the lack of animal protein in food rations in sub-Saharan countries. The Bruchidae family (Bruchidius atrolineatus, and Callosobruchus maculatus) occupies first place in the diversity of insects that have adapted to cowpea stocks. Bruchidius adults colonize cowpea crops from the start of flowering. Females lay eggs on the pods as soon as they begin to form. Larvae and pupae are therefore already present in the harvested products, which are stored in granaries. The larvae penetrate the seeds, at the expense of which they carry out their embryonic post-development. The damage caused by this insect pest can be considerable if no protective measures are taken. To prevent damage caused by C. maculatus during cowpea storage, farmers generally expose seeds and pods to sunlight for several days before storing them. The aim of this work was to study the impact of sun pre-exposure and cold pre-treatment on the different development stages of C. maculatus. The results obtained show that C. maculatus adults are more sensitive to solar radiation than to cold conservation; in the case of pre-exposure to the sun, a 100% mortality rate is observed from 1 h onwards, whereas the same result is obtained at 2h30 min in the case of cold pre-treatment. On the other hand, cold had a greater effect on eggs, L2 larvae and L4 larvae than sunlight. For eggs, a 30 minutes cold pre-treatment gives a 100% mortality rate, whereas pre-exposure to the sun requires 45 minutes. L2 larvae and L4 larvae gave respectively 100% mortality from 2h and 2h30mn cold; while for sun pre-exposure respective durations of 2h30 min and 3h were recorded.

Bruchidius atrolineatus (Coleoptera-Bruchinae) est un ravageur important du niébé dans les champs et dans les stocks. Des individus mâles appartenant à des populations de cette bruche du niébé obtenus des graines des graines de la taille différente ont été comparées au moyen d‘une analyse factorielle discriminante (AFD) portant sur 17 variables morphologiques. La taille moyenne de chaque variété a été mesurée. L’analyse des données montre que les individus issus des graines de grandes tailles sont plus grands que ceux issus de petite taille. Ceux issus des graines de petite taille se caractérisent par la distance minimale entre les yeux ventralement (dvy) et de la plus grande dimension du tibia 3 (Lt3). Les individus mâles issus de graines de grande taille se distinguent par la longueur de l’antenne (Lan), la distance minimale entre les yeux dorsalement (Lmf), de la longueur maximale de tête (Lmt), de la largeur du pronotum au centre (Lap), de la plus grande dimension de la fémur 3 (Lf3), la longueur maximale de la cellule radiale de l’aile postérieure (Loc), de la longueur de l’élytre (Loe), la plus grande dimension du coxa 3 (Lmc), la longueur du premier sternite abdominale (Los), de la largeur du premier sternite abdominal (Las) la longueur (Lpy) et largeur (lpy) du pygidium (Figures 3 et 4). L’examen de la valeur de F montre que les variables possédant globalement le plus fort pouvoir discriminant sont par ordre de F décroissant: Lap (F=1007,33), Lmf (F=273,94), Lmt (F=159,38), Las (F=123,25), Lf3 (F=74,14), Lmc (F=47,41), Loe (F=43,03), Lpy (F=24,50), Lt3 (F=28,36), Lan (F=26,71), dvy (F=25,35), lpy (F=24,50), Loc (F=16,82), Los (F=9,28).

Bambara groundnut (Vigna subterranea l.), third food legume in Africa, is the largest in terms of production and consumption after the peanut (Arachis hypogeae) and Cowpea (Vigna unguiculata walp.). The valorisation of this culture is one of the best alternatives to ensure the food security of populations faced with the decline in the production of food crops such as millet, sorghum or wheat. To achieve this goal, a better knowledge of the genetic diversity of this culture is more than necessary. Therefore, followed by exploration of accessions collection was made across the country. All the areas visited were geo referenced and a map has been prepared. In total one hundred and fifteen (115) Bambara groundnut accessions were collected within six (6) regions of Niger with fifty (50) locations visited throughout the different growing areas. Fourteen morphotypes numbered Ne-01 to Ne-14 were identified after the collection. Following carried out discussions, the yellow color Ne-01 morphotype is the most appreciated both by producers and consumers. It is also clear that this culture of Bambara groundnut is practiced on small areas by both women and men. The choice of the seedling period is the same as well among women than among men. The production is destined for self-consumption or for sale depending on the quantity harvested. Chemicals, ash, salt, natron, cans are commonly used for the seeds conservation. Several types of dishes are made based of Bambara groundnut. In addition, Bambara groundnut has therapeutic values in some farmer's areas.