Allelopathic activity of aqueous decomposed leaf litter extracts on the germination and early seedling growth of cowpea (Vigna unguiculata) in Aden, Yemen

Allelopathic effect of Aqueous decomposed leaf litter from four common trees and shrubs in Aden governorate, Yemen was investigated on the germination and early seedling growth of Cowpea, the test crop was subjected to four concentrations of 25, 50, 75 and 100% of the aqueous extract, while a control was maintained at 0% extract level. The study carried out in the laboratory of Botany at Faculty of Education, University of Aden.
The Percentage of germination, Germination rate per plate, radicle length, plumule, (hypo and epicotyl lengths) observed. Data was recorded at 24 hours interval after germination for 15 days, the research revealed delayed germination rate per plate and a significant reduction in the radicle length and germination percentage (data was collected on percentage germination; plant height. Results obtained showed that significant reduction in the growth parameters considered at 100% and 75%, while at 50% and 25% the difference was not significant.
From the result obtained, it can concluded that Conocarpus lancefolius and Thevetia peruviana possess allelopathic effect that inhibit the germination and early seedling growth of Cowpea, hence at 100% concentration.