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The experiment was conducted to evaluate variability estimates for yield contributing and nutritional traits in 60 tomato (Solanum lycopersicum L.) hybrids and their parents. The trial was laid out in alpha lattice design and data pertaining to 13 quantitative, six nutritional and four qualitative characters have been presented. The estimates of mean, range, phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) revealed significant phenotypic and nutritional variations among the genotypes for most of the characters under study. The principal component analysis showed that number of marketable fruits, number of non-marketable fruits, marketable yield, total yield, total number of fruits, number of fruits per cluster, fruit length and width, beta carotene, vitamin C, lycopene and acidity content contributed most to observed variations in the population. Five clusters were identified among the tomato population and they significantly associated with high nutritional content, high yield, yield contributing traits and fruit size related traits. For association among traits, moderate to very strong significant (P < 0.05) positive correlation was recorded for yield with number of branches (0.40), number of marketable fruit (0.84), number of non-marketable fruits (0.71), marketable yield (.98) and non-marketable yield (0.71). On the contrary, brix recorded weak negative significant correlation (-0.32) with non-marketable yield-while no significant association was observed between the agronomic and nutritional variables. Estimates of moderate to high heritability in the broad sense coupled with high genetic advance as a percentage of mean showed the feasibility of improving fruit nutritional quality, yield and yield contributing traits in this population through selection.

African eggplant (Solanum aethiopicum L.) is an important but underutilized leafy and fruit vegetable. Systematic characterization of available eggplant accessions for morphological and nutritional traits is paramount to their genetic improvement. This study characterized the diversity among selected S. aethiopicum accessions from Nigeria to identify promising genotypes for future breeding activities in the region. Twenty new purified African eggplant accessions collected from farmers’ fields were characterized using morphological and nutritional descriptors. The accessions varied significantly in qualitative, quantitative and nutritional parameters. Top performers for selected yield-contributing traits and nutritional parameters were NHEPA54, NHEPA39-1, NHEAP10, NHEPA10, NHEPA1, NHEPA56, NHEPA23 for vitamin C, iron, calcium, days to flowering, number of branches, plant height at maturity and number of fruits per plant respectively. The first four principal components accounted for 72.42% of total variability. The first principal component with the largest variation (28.77%) was loaded with number of branches, plant height at maturity, number of fruits per cluster, number of fruits per plant and fruit width. A significant positive association was exhibited between iron and yield-increasing traits such as number of fruits per plant (r = 0.532) and number of fruits per cluster (r = 0.551). Plant height at maturity positively correlated with vitamin C (r = 0.492) indicating predictable success in selecting top-performing eggplant genotypes combining high-yield potential and nutritional content. Top-performing eggplant genotypes identified in this study could be deployed as donors for a hybridization programme to develop new eggplant varieties with higher yield potential and improved nutritional quality.

FUNAABOR-2 is a popular Ofada rice variety grown in a large area under rainfed upland condition across western states of Nigeria. We used the combination of phenotypic and marker-assisted selection (MAS) to improve grain yield of FUNAABOR-2 under drought stress (DS) at the reproductive stage via introgression of two drought quantitative trait loci (QTLs), qDTY12.1 and qDTY2.3. Foreground selection was carried out using peak markers RM511 and RM250, associated with qDTY12.1 and qDTY2.3, respectively, followed by recombinant selection with RM28099 and RM1261 distally flanking qDTY12.1. Furthermore, BC1F2-derived introgressed lines and their parents were evaluated under DS and non-stress (NS) conditions during the 2015–2016 dry season. Overall reduction of grain yield under DS compared to NS was recorded. Introgressed lines with qDTY12.1 and qDTY2.3 combinations showed higher yield potential compared to lines with single or no QTL under DS, indicating significant positive interactions between the two QTLs under the FUNAABOR-2 genetic background. Pyramiding of qDTY12.1 and qDTY2.3 in the FUNAABOR-2 genetic background led to higher grain yield production under DS and NS. Keywords: drought, foreground selection, introgressed line, peak marker, yield potential, rice, quantitative trait locus