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Seeds of 24 West African rice (Oryza sativa L.) genotypes were evaluated for seed vigour traits in the laboratory and field in two cropping seasons at the Research Farm of Federal University of Agriculture, Abeokuta, Nigeria. Seed yields of these genotypes were also determined in the field during the two seasons. Data collected on seed vigour traits were subjected to multivariate analysis including principal component analysis (PCA) and cluster analysis. The first three axes of the principal component analysis across the two seasons captured 86.34% of the total variation among the entries and identified seedling vigour index-I, seedling vigour index-II, speed of germination index, percentage germination, seedling establishment, emergence percentage and seed yield per plant as the characters contributing most to the variation. Cluster analysis classified these genotypes into four distinct groups based on germination and emergence percentages. Fifteen of the genotypes with mean values of between 60.43% and 65.18%, clustered in group 1, two genotypes each with mean values of 65.71% and 58.81% and 20.11% and 29.49% clustered in groups II and IV respectively while the remaining five genotypes with mean values of between 55.19% and 55.88% clustered in group III. Hybridization of genotypes across dusters could lead to increase in heterosis in cross progenies. Those characters identified by PCA could be included in the crop improvement programme for improved seed quality within West African low land rice germplasm.

A study was conducted during 2008 to 2009 in 12 environments in Nigeria, Benin Republic and Togo to evaluate genetic variation and heritability of yield and related traits in 48 rice genotypes. The experiments were laid out in a randomized complete block design (RCBD) with three replications. Genotypes differed significantly at p > 0.001 for all the traits studied, which implies that the genotypes contain adequate genetic variability. Phenotypic coefficients of variation (PCV) were higher than genotypic coefficients of variation (GCV) in all the characters across the 12 environments. High heritability estimates were obtained for days to flowering (91.37), days to maturity (86.86), plant height at maturity, number of tiller per meter square, panicle shattering, panicle threshability, panicle per meter and panicle length (72.21) suggesting that the traits are primarily under genetic control. High estimates of heritability, GCV and genetic advance (GA) observed for grain yield is an indication that selection for grain yield could be achieved through phenotypic performance. Furthermore, high estimates of heritability, GA and GCV recorded in these characters could be explained by additive gene action. Low estimates of heritability, GCV and GA recorded for grain yield and number of grains per panicle could be due to non-additive gene effect suggesting that these traits were less responsive to specific environment influences. Grain yield recorded highly significant positive correlation with panicle length (0.28), leaf width (0.40), grain length (0.30), number of panicles per meter square (0.19) and1000-grain weight (0.17). It correlated negatively with basal leaf sheath coloration (-0.33) and grain width (-0.20) in the 12 environments. The current study indicated that more number of tillers, panicles per meter square, long panicles, high number of primary and secondary branch panicles and large 1000-grain weight are important yield related traits and could be used for selection in rice breeding programs.

This study assessed the influence of three plant populations (18518, 27777 and 40000 plants ha -1 ) on fruit and seed yield characters in 16 genotypes of Capsicum frutescens in 2010 and 2011 cropping years using a 3 x 16 split plot arrangement fitted into a randomized complete block design. Plant population and genotype formed main and sub-plots, respectively. Data collected on fruit and seed yield characters were subjected to analysis of variance after which means were separated using Fisher's Least Significant Difference. Correlation analysis was also carried out among the characters. Significant and highest (P < 0.01) number of fruits per plant, single fruit weight, fruit weight per plant, number of seeds per fruit, 100 seed weight, seed weight per plant and seed weight per fruit were obtained under 18518 plants ha -1 while highest (P < 0.05) fruit yield ha -1 (11.3 tons) and seed yield ha -1 (698.7 kg) were obtained under 40000 plants ha -1 . Top fruit and seed yielding genotypes across the three plant population were PP9955-15 and Chilli 14, respectively. Number of fruits per plant showed negative and highly significant correlation with single fruit weight, fruit length, fruit width, number of seeds per fruit, 100-seed weight and seed weight per fruit. Significant positive or negative correlations were also observed among other characters. Plant population of 40,000 ha -1 using 50 x 50 cm spacing is recommended for high fruit and seed yield in C. frutescens production.

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