CONTROL OF BEAN WEEVILS USING SEED EXTRACT OF GINGER (Zingiber officinale) AND TUMERIC (Curcuma longa)

Bean (Phaseolus vulgaris) belonging to the family Fabaceae is one of the commonly  grown and consumed  crop in Africa especially Nigeria. In most developing countries of the world like Nigeria, beans constituent constitutes a major protein source for human consumption; it can also serve as an animal feed. However, a sizeable amount of stored beans´ grain is often lost by pest infestation. Zabrote subfasciatus (Bean weevil) is one of the most common bean pests. Z. subfasciatus grows exponentially on untreated grain and can account for up to 100% damage of the product. This study examined the control of bean weevil using the seed extracts of Ginger (Zingiber officinale) and Turmeric (Curcuma longa). A laboratory analysis of the sample was adopted in carrying out the work. Beans samples were bought from Unizik junction market and about 30 pieces of bean weevils were collected from the already infested bean. Turmeric and ginger were extracted using a Soxhlet extractor and ethanol as the extraction solvent. The weevil specimens were treated with 4mg/l and 8mg/l for each of the extracts respectively. From the analysis, results showed that 4 mg/l dosage of turmeric extract recorded 23% mortality rate of the bean weevil while the same dosage of ginger extract recorded 17% mortality only. The results also shows that 8 mg/l dosage of turmeric extract yielded a higher mortality rate of bean weevil with about 29% than ginger extract which yielded lower mortality rate of bean weevil with about 20%. Turmeric extract of 8 mg/l dosage was more effective as compared to the 4 mg/l as there is high mortality rate among specimen treated with 8mg/l dose turmeric extract than ginger extract. Therefore, the study recommended that turmeric extract should be used by farmer as a control of weevil during and out of storage to prevent weevil infestation and damage on beans.