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Background of the Study: Rice (Oryza sativa L) is an important staple food crop that feed over half of the global population and it has become the cereal that provides a major source of calories for the urban and rural poor in Africa. Rice has is the second most important food staple after maize in Ghana and its consumption keeps increasing as a result of population growth, urbanization and change in consumer habits. Rice yield across Ghana is far below achievable yield. The need for increasing rice yield depends not only on cultural/traditional practices but also on their inbuilt genetic potential to withstand stresses. Adequate diverse rice germplasm is a pre-requisite for breeding varieties to meet local biotic, abiotic and grain quality challenges. Knowledge of germplasm diversity and genetic relationships among breeding materials is valuable information for crop improvement. Aim: To identify the diversity among assembled rice germplasms for evaluation and possibly exploit its genetic variability for earliness for cultivation in the Guinea and Sudan Savanna ecologies. Study Design: The experiment was conducted at CSIR-SARI research station, Nyanpkala. Using a Randomized Complete Block Design with two replications, and a plot size of 4 m x 3 m was used. Field data taken included 10 qualitative and 11 quantitative traits. The data were statistically analyzed for various descriptive statistics. Results: Correlation analysis, Principal Component Analysis (PCA) and Cluster analysis were used to assess genetic variability. Most of the morphological traits showed remarkable differences in their distribution. Five significant principal components were identified accounting for 78.11% of the total variation. Cluster analysis based on the morphological data grouped the germplasm into two distinct clusters suggesting diversity among the assembled rice germplasms. Conclusions: The rice germplasm used in the present study displayed variability for most of the studied traits with the exception of ligule. Twenty one out of the 100 germplasm were distant from the rest, and were selected to constitute a core collection for further improvement. Recommendations: Diversity revealed in this study is narrow. It is, therefore, recommended that rice breeding programs in Ghana should include new genetically unrelated genotypes in order to broaden the genetic base of Ghanaian rice germplasm.

A study to screen F2 populations obtained from IT10K-837-1 x Sanzi for resistance to M. sjostedti. A total of 351 F2 plants were screened under field conditions and each line rated visually for thrips damage score, flower abortion rate, number of pods per plant and number of thrips per flower. The study was conducted during the 2020 cropping seasons where F2 seeds were planted under field conditions. Thrips damage score, flower abortion rate, number of pods per plant, and number of thrips per bloom was all visually scored for each accession. The data from the field and laboratory were analyzed using GENSTAT edition 12 to determine if there were any major variations among the cowpea genotypes. The approximate correlations among all measured parameters, including damage scores at 45 DAP, 55 DAP, 65 DAP, using were established using Breeding View software and heritability values were also calculated. There was a strong and significant correlation between thrips population and damage rating during the planting season. Thrips resistance levels identified in most genotypes in this study are interesting compared to the resistant check Sanzisabinli and can be further exploited for future studies to develop resistant varieties to improve cowpea yields.

Genotype by environmental interaction is important for breeding improved cowpea genotypes. The study was designed to identify promising inbred lines with high yield potential, stable mean yield with specific adaptation to a particular environment or environments. The study was conducted at three locations namely Nyankpala, Tumu, and Damongo. Twenty-two inbred lines plus 2 contrasting parents used to generate inbred lines were the test genotypes. Randomized complete block design with 4 replications was used. Seeds were planted at each location but were later thinned to one plant per hill. Each plot contained 5 rows of 10 plants per row with plant spacing of 60 cm between rows and 20 cm within rows with the number of entries being 24 plots giving the total plots as 96 plots for each location. Data collected were days to first flowering, 50% flowering, number of pods per plant, number of seeds per pod and hundred seed weight and grain yield. Data were subjected to analysis of variance using Gen Stat statistical package 12th edition. Combined analysis of variance across locations for grain yield were determine. Results showed significant genotypic differences among inbred lines for studied traits. significant genotype by environment interaction was observed for days to 50% flowering, ranging between 42 and 45 days. Number of pods per plant, number of seeds per pod and biomass also showed variable responses across locations. Phenotypic correlation analysis for days to flowering and maturity did not have any influence on yield, as genotypes 116, 189, 131 flowered within 43 and 45 days with corresponding yields of 1.89,1.82 and 1.7 tonnes per hectare. Yield variability showed the possibility for selecting location specific adapted lines as well as across all three locations.