Diversity among selected African nightshade genotypes found in Kenya

African nightshade (Solanum nigrum L.) is widely used as leafy herbs and vegetables, as a source of fruit and for various medicinal purposes in the world. Nonetheless the diversity of Solanum nigrum in terms of its morphological characteristics is not well known. The objective of this study was to examine morphological characteristics of selected African nightshade (ANS) genotypes. The study was conducted during the long rainy season between March – July 2015 and short rainy season between October-December 2015. The ANS genotypes were obtained from the Kenya National Gene Bank, AVRDC-Tanzania and Kenyan farmers. Nineteen genotypes were grown at two research stations using alpha lattice design replicated three times. Data were collected on both quantitative (plant height, leaf width, leaf length: leaf width ratio and number of berries per panicle) and qualitative (growth habit, leaf shape, leaf margin, flower and berry color) traits. Results showed that there were significant (P ≤ 0.05) variations in both quantitative and qualitative traits. In terms of plant height, AVRDC TZ-BG 23 recorded a height of 120cm being the tallest genotype while AVRDCTZ-BG 14 and AVRDC TZ- MW 13 recorded heights of 27cm and 21cm, respectively and were the shortest genotypes. The improved genotype and AVRDC TZ (SS49) genotype produced the widest leaves, 12cm wide, while OARA type 1 and GKB 050287 had narrow leaves 2.1cm and 2.5cm, respectively. In terms of leaf shapes, the genotypes displayed three types in which GBK Genotype, Managu Nakuru County, AVRDCTZ-SS49 and the improved genotype leaves were ovate shaped, OARA type 1 and 2 leaves were rhomboid shaped while the remaining genotypes had lanceolate shape. The results further indicated that AVRDC-TZ -SS49 produced flowers with purple petals compared to white petals that were produced by all the other genotypes. Besides, there were variations among genotypes in mature berry colour in which 10 genotypes produced green berries, Kakamega 1, 2 and 3 orange berries and the improved genotype, GBK genotype, Managu Nakuru county, OARA type 1 and 2, and AVRDC –TZ (SS49) with purple berries. This study has documented morphological diversity that can be deployed in breeding programs for the ANS.