Abstract:
This study was carried out to maximize dry matter yield of Vigna unguiculata L. (cowpea) by application of Allium cepa peel extract. The experiment was conducted at a home garden, Mailapitiya, Kandy in May to September 2021 in a Randomized Complete Block Design. There were six treatments in six replications comprised of different percentages of Allium cepa peel extract expressed as, T1 was control treatment by using normal water and T2 - 20%, T3 - 40%, T4 - 60%, T5 - 80% and T6 - 100% extract concentrations. The peel extract was prepared by
soaking 100 g of peels in one-liter water for 48 hours at the room temperature then extract was diluted according to the treatments. The application of Allium cepa peel extract was started at two weeks after seeding and the plant performance was recorded in vegetative phase and in harvesting phase. The results were confirmed that application of Allium cepa peel extract had significant (P<0.05) effects on tested parameters over the control. The application of 40% (v/v) concentration Allium cepa peel extract increased the number of trifoliate leaves, root length, dry weights of stem, leaves, root and crop residue after harvesting pods. But the application of
100% (v/v) concentration of Allium cepa peel extract was significantly increased pod weight per plant among the treatments. The maximum mean value of dry matter yield was recorded in T6 (782.44 g/m2) and the minimum mean value was recorded in T1 (327.11 g/ m2). According to the statistically analyzed results, 100% of Allium cepa peel extract gave a higher dry matter yield of Vigna unguiculata (L) but there was no significant variation on pod weight and dry matter yield between T5 and T6. Therefore, Allium cepa (onion) peel at 80% could be used for
increasing the pod and dry matter yield of Vigna unguiculata (L).
