Comparative evaluation of the germination capability of three morphologically different wild genotypes of Corchorus olitorius L. from Northern KwaZulu-Natal, South Africa

Abstract

Corchorus olitorius L. is a wild plant utilised as a vegetable in many parts of Africa. Wild indigenous vegetables have been recommended to alleviate nutritional deficiencies and household food insecurity. Efforts to domesticate and cultivate wild C. olitorius and other wild vegetables are being hampered by seed dormancy. The main cause of dormancy in C. olitorius has been suggested to be an impermeable seed coat. This study evaluates the response of wild genotypes of C. olitorius with different seed sizes to various dry heat and hot water treatments. Steeping seeds in boiling water (95°C) for 10 s and soaking seeds in a hot water bath at 80°C for 10 min resulted in a highest response to germination in the tested genotypes of this species. The study also recorded significant interactions between heat treatment and seed sizes. It was therefore concluded that genotypes of C. olitorius with different sizes require diverse durations of exposure to heat treatment methods to break dormancy caused by an impermeable seed coat.