IOSR Journal of Agriculture and Veterinary Science (IOSR-JAVS) e-ISSN: 2319-2380, p-ISSN: 2319-2372. Volume 13, Issue 3 Ser. II (March 2020), PP 23-26 www.iosrjournals.org DOI: 10.9790/2380-1303022326 www.iosrjournals.org 23 | Page Efficacy of Various Neem Products in Control of Storage Pests (Callosobruchusmaculatus) of Cowpea (Vignaunguiculata) 1 Rajab, Y.S.* and 2 Abdullahi, U. 1 Department of Crop Production Technology, Federal Polytechnic, Bali. 2 Department of Agricultural and Bio-Environmental Engineering Technology, Federal Polytechnic, Bali. Corresponding author: Rajab, Y. S. Abstract: experiment was carried out in a storage cubicle at Department of Crop Production Technology, Fed- eral Polytechnic, Bali to determine the efficacy of various neem products in the control of storage insect pests (Callosobruchusmaculatus) of cowpea (Vignaunguiculata). Three kilograms of the beans was put into three (25 cm x 30 cm) cotton bags and each treated with 75gram neem leaf, bark and seed powder respectively; and ten pairs of both sexes of Callosobruchusmaculatus were introduced into each bag and the set up replicated into 40 (a total of 120 treated bags). Another 40 bags which contained cowpea and the pests without treatment served as control. Each bag was tied with string. The treated and untreated bags (160 bags) were arranged in separate compartments of the cubicle and allowed to stay for three months. Parameter assessed was weight loss of the cowpea and data generated were subjected to one-way Analysis of Variance (ANOVA) using “R” statistical package. Least significant differences (LSD) were also used for mean separation at p = 0.05. The results showed significant differences among means of the treatments at p < 0.01. The control experiment recorded the highest mean of beans weight loss (1.16) while the least mean weight loss was observed in bags treated with neem seed powder (0.92); followed by those treated with bark powder (0.96), then leaf powder (1.03). Hence both the null hypotheses were rejected. Therefore, neem seed powder is most promising in the botanical control of storage pests (C. maculatus). Key words: Efficacy, neem, storage pest, cowpea --------------------------------------------------------------------------------------------------------------------------------------- Date of Submission: 13-03-2020 Date of Acceptance: 28-03-2020 --------------------------------------------------------------------------------------------------------------------------------------- I. Introduction Cowpea is an annual legume crop which matures in 3-4 months, which also belongs to the family Leguminoceae(Inusa, 2019). It grows very well on a good and friable soil which receives moderate rainfall of 760 mm to 1500 mm; and this is why it is commonly cultivated in Semi-Arid northern Nigeria (Singh et al., 1997). Sigmund et al. (1991) reported that one-third of the world’s population consume diet deficient in protein and this deficiency is more pronounced in humid tropical countries. Sigmund et al. (1991) further observed that these deficiencies could be balanced by combination of various food items; hence, it was suggested that a diet with 1/3 beans and 2/3 maize could give a biological value of 100. Being a cheap leguminous crop which pro- vides good quality protein, cowpea augments the staple carbohydrate widely consumed in Nigeria (Muonekeet al., 2012). Mainaet al. (2012) reported that before harvest and during storage cowpea seeds are prone to a large number of species of insect pests, which constitute a major setback in its production. Therefore, preserving agri- cultural products for future use is the most important post-harvest operation; however, this is impeded by the actions of storage pests. Pests of Cowpea – bruchids in the family Bruchidae are serious pests of grain legumes in storage (Laleet al., 2002). They cause substantial losses through seed perforation, reduction in weight, market value and germination ability of seeds (El-Atta, 1993). For instance, the larvae of Callosobruchusmaculatusfeed and de- velop exclusively on the seed of legumes (Fabaceae), while the adults do not require food or water and spend their life span (one-two weeks) mating and laying eggs on beans (Myers et al., 2006). Profit (1997) reported that about 5% of cowpea pods are infested by cowpea weevils in northern Nigeria and during inoculation, the larvae hatch directly from the egg and burrow through the pod wall and finally into the seed where they develop and puppet. Pests Control –Cowpea is infected by various groups of insects from emergence to reproduction up to storage. Therefore, careful spray of insecticides is the most economic and reliable means of pest control (Ag- bato, 2011). However, environmental pollution and health hazard pose by synthetic pesticides makes it neces- sary for farmers to adopt the use of alternative and safer means of combating problems of insect pests. Several control measures were postulated by different workers, which include use of wood ash, solarisation, conven- tional insecticides to botanical insecticides (Zittleret al., 1997). For instance, neem products are botanical insec-