Effets des traitements physico-chimiques des graines sur la germination, la croissance et la production de la morelle noire (Solanum nigrum L.) dans les conditions de Kinshasa/Mont-Amba, République démocratique du Congo

Abstract

Black nightshade (Solanum nigrum L.) is a vegetable of high nutritional and medicinal value. Given its importance as a food crop, intensifying production and ensuring a regular supply in Kinshasa require, among other factors, the use of high-quality seeds with reduced dormancy. This study aimed to identify accessible physico-chemical treatments capable of enhancing seed germination and shortening the emergence time of S. nigrum after sowing. The laboratory germination test was conducted according to the rules of the International Seed Testing Association (ISTA), whereas the field experiment followed a randomized complete block design. Treatments improved seedling emergence, with gibberellic acid reaching 86.20%, compared with 22.50% in the untreated control. Under laboratory conditions, the highest germination rate obtained with gibberellic acid was 76.75%, compared with 5.75% in the control. Gibberellic acid treatments, particularly after 3 h of soaking, and the combined red + green D.I.Grow treatment were the most effective for breaking seed dormancy. However, production parameters did not differ significantly among treatments. These findings indicate that gibberellic acid was the most effective option among the treatments evaluated; mixed D.I.Grow, hot water at 50 °C, and lukewarm water may also be considered depending on input accessibility.