Cowpea is a vegetable that contributes to food security in Guinea. Despite its importance, more than 30% of its production is lost between harvesting, storage and consumption. The main cowpea pest is Callosobruchus ma...Cowpea is a vegetable that contributes to food security in Guinea. Despite its importance, more than 30% of its production is lost between harvesting, storage and consumption. The main cowpea pest is Callosobruchus maculatus. The commonly used control strategy is essentially based on chemicals whose use is toxic, expensive and restrictive. In the search for alternatives to chemical control, this work was undertaken to evaluate the insecticidal potential of Ageratum conyzoid leaf powders and Securidaca longepedunculata roots. Powder toxicity and insecticidal efficacy tests were performed separately on groups of 20 Callosobruchus maculatus using 3 doses of Ageratum conyzoid leaf powders and Securidaca longepedunculata roots in jars each containing 100 g cowpea. The mortality of Callosobruchus maculatus and the impact of powders were noted respectively for 96 h and 4 months after infestation. The germination capacity of the treated seeds was assessed at the start of the study. Doses of 1 and 8 g of Ageratum conyzoides leaf powders and Securidaca longepedunculata roots were applied respectively to every 100 g of cowpea and led to 100% mortality of Callosobruchus maculatus. At these same doses, more than half of the treated seeds were attacked during the 4 months of storage. Germination tests have shown that powders of Ageratum conyzoides leaves and roots of Securidaca longepedunculata have no negative effect on the germination power of cowpea seeds. Therefore, they could be considered as excellent bio-insecticides that socio-professional strata (farmers and warehouse workers) can use in the fight against cowpea insects intended for storage.展开更多
The present study, which aims to contribute to the valorization of Capsicum chinense, focuses on ethnobotanical investigations and evaluation of insecticidal activity on Sitophilus zeamaïs and Aphis craccivor...The present study, which aims to contribute to the valorization of Capsicum chinense, focuses on ethnobotanical investigations and evaluation of insecticidal activity on Sitophilus zeamaïs and Aphis craccivora, as well as the germination power of infected maize and peanut grains treated and not treated with Capsicum chinense leaf powder. To do this, the moisture content of corn and peanuts was determined by the techniques: drying in the sun and in the oven. The insecticidal effect of the powder was tested on maize and peanut kernels infected by the AGRAR (2013) method, followed by a test of the germination potency of these treated grains. The average moisture values of corn and groundnut kernels are 14.51% and 12.25% respectively. The results show, a higher insecticidal efficacy of Capsicum chinense leaf powder on Sitophilus zeamaïs and Aphis craccivora with doses (2, 4 and 8 g). The average germination rates of maize and peanut kernels infected and treated with this powder are: (16.5%;63%;99.5%) and (21.25%;96.5%;99.75%), respectively. This study could be a bio-insecticide alternative for the peasant community in the conservation of cereal and legume products.展开更多
文摘Cowpea is a vegetable that contributes to food security in Guinea. Despite its importance, more than 30% of its production is lost between harvesting, storage and consumption. The main cowpea pest is Callosobruchus maculatus. The commonly used control strategy is essentially based on chemicals whose use is toxic, expensive and restrictive. In the search for alternatives to chemical control, this work was undertaken to evaluate the insecticidal potential of Ageratum conyzoid leaf powders and Securidaca longepedunculata roots. Powder toxicity and insecticidal efficacy tests were performed separately on groups of 20 Callosobruchus maculatus using 3 doses of Ageratum conyzoid leaf powders and Securidaca longepedunculata roots in jars each containing 100 g cowpea. The mortality of Callosobruchus maculatus and the impact of powders were noted respectively for 96 h and 4 months after infestation. The germination capacity of the treated seeds was assessed at the start of the study. Doses of 1 and 8 g of Ageratum conyzoides leaf powders and Securidaca longepedunculata roots were applied respectively to every 100 g of cowpea and led to 100% mortality of Callosobruchus maculatus. At these same doses, more than half of the treated seeds were attacked during the 4 months of storage. Germination tests have shown that powders of Ageratum conyzoides leaves and roots of Securidaca longepedunculata have no negative effect on the germination power of cowpea seeds. Therefore, they could be considered as excellent bio-insecticides that socio-professional strata (farmers and warehouse workers) can use in the fight against cowpea insects intended for storage.
文摘The present study, which aims to contribute to the valorization of Capsicum chinense, focuses on ethnobotanical investigations and evaluation of insecticidal activity on Sitophilus zeamaïs and Aphis craccivora, as well as the germination power of infected maize and peanut grains treated and not treated with Capsicum chinense leaf powder. To do this, the moisture content of corn and peanuts was determined by the techniques: drying in the sun and in the oven. The insecticidal effect of the powder was tested on maize and peanut kernels infected by the AGRAR (2013) method, followed by a test of the germination potency of these treated grains. The average moisture values of corn and groundnut kernels are 14.51% and 12.25% respectively. The results show, a higher insecticidal efficacy of Capsicum chinense leaf powder on Sitophilus zeamaïs and Aphis craccivora with doses (2, 4 and 8 g). The average germination rates of maize and peanut kernels infected and treated with this powder are: (16.5%;63%;99.5%) and (21.25%;96.5%;99.75%), respectively. This study could be a bio-insecticide alternative for the peasant community in the conservation of cereal and legume products.
