INTEGRATION OF HOST RESISTANCE AND BOTANICALS IN THE MANAGEMENT OF INFESTATION AND DAMAGE BY CALLOSOBRUCHUS MACULATUS FABRICIUS (COLEOPTERA: CHRYSOMELIDAE)

Abstract

The use of synthetic insecticide is probably the most effective means of reducing the damage caused by pest. However, with its attendant problems on human health and the environment, integrated pest management (IPM) has been canvassed as one of the viable alternatives for abating these problems. Therefore, this study sought to evaluate the effect of integrating host resistance and powders of Syzygium aromaticum and Piper guineense in reducing infestation and damage of cowpea seeds by Callosbruchus maculatus (F.) The study was carried out at an ambient temperature ranging from 25-350C and relative humidity of 65-75%. Seven cowpea cultivars; Drum, Milk, Oloyin, IT07K-292-10, IT07K-318-33, IT99K-573-1-1 and IT99K-573-2-1 were used for this study. The result of the effect of cowpea varieties on C. maculatus showed that there was a significant difference (p>0.05) between the highest oviposition value of 146.00±13.32 on the IT07K-292-10 cultivar and the least oviposition recorded from IT99K-573-1-1 (55.00±11.5). Milk cultivar showed the least adult emergence of 11.67±2.91; there was a significant difference (p>0.05) when compared to the highest adult emergence on IT99K-573-1-1 (84.99±5.88). Piper guineense and Syzygium aromaticum powder tested against cowpea weevil exhibited ovicidal action and reduced the number of adult emergence of C. maculatus. S. aromaticum powder applied at 0.4g was the most effective among the three dosages applied P. guineense applied at 0.4g showed Milk cultivar had the lowest adult emergence of 18.33±7.45, while Oloyin cultivar had the highest adult emergence. IT07K-292-10, IT99K-573-2-1, IT99K-573-1-1 and Oloyin cultivar were the most susceptible to C. maculatus infestation having the highest oviposition, and adult emergence and seed damage. Milk cultivar was the least susceptible among the cultivars. In conclusion, application of S. aromaticum in combination to host varietal resistance gave better protection to infestation by C. maculatus than P. guineense.