Effectiveness of hermetic bags and botanical pesticides in reducing quantitative post-harvest losses of beans (Phaselous vulgaris) · Electronic Theses and Dissertations

Author

Bridget Mafunga

Title

Effectiveness of hermetic bags and botanical pesticides in reducing quantitative post-harvest losses of beans (Phaselous vulgaris)

Abstract

ABSTRACT
Bean weevils are important storage pests of legumes worldwide, causing 60-90% losses among Zimbabwe’s smallholder farmers. The majority of farmers do not apply any measures to control the pest while a few use synthetic pesticides that pose harm to users and the environment. This study evaluated the effectiveness of hermetic bags and botanical pesticides in reducing quantitative post-harvest losses in beans caused by the weevils. Three types of hermetic bags were used in the study (triple, double and single hermetic bags). Also Aloe barbadensis miller (Aloe), Azadirachta indica (neem) and Helianthus annus L. (Sunflower) powder were used as botanical pesticides on the experiment. Shumba pesticides was used as positive control on the experiment. Before commencement of the experiment, the researcher cleaned the seed using winnowing method to remove all the impurities which may contaminate the results of the experiment. Also bean seed was refrigerated for 48 hours to ensure that all weevils were killed before the beginning of the experiment. In each hermetic bag, the researcher put 2kgs of bean seed and ordinary bags were used for sugar beans with botanical pesticides, shumba pesticide and negative control bag. In all bags, the researcher put 2kgs of sugar beans. The balance scale was used to weigh the bean seed. The treatments were arranged in a completely randomized design, and replicated three times. Bean weevil mortality was assessed at 2, 4, 6 and 8 week intervals. Also percentage weight loss and moisture content was assessed at 2, 4, 6 and 8 weeks intervals. . There was significant difference (p<0.05) in number of weevil mortality and grain weight loss among treatments. The results showed that hermetic bags were most effective especially triple and double hermetic bags as evidenced by high weevil mortality percentage, low or none multiplication percentage and maintenance of weight and moisture percentage. It concluded that hermetic bags have good properties to manage bruchids in legume storage and could be used as alternative control option.

Date

JUNE 2024

Publisher

BUSE

Keywords

Key words: botanical pesticides, grain weevils, hermetic treatments, mortality, multiplication, sugar beans and weight loss.

Supervisor

Dr. T. J. Chikuvire