Sorghum (Sorghum bicolour (L.) Moench) grown under rain-fed conditions is usually affected by drought stress at different stages, resulting in reduced yield. The assessment of variation in morpho-physiological traits contributing towards drought tolerance at these stages is of vital importance. This study was conducted using a split plot design with three replications to evaluate 25 sorghum accessions at post flowering stage under well watered and drought stress conditions at Hamelmalo Agricultural College. The data of 14 different morpho-physiological traits were subjected to analysis of variance, estimation of genetic variability and heritability and principal component analysis. We analyzed variance for seedling vigor, number of leaves, leaf area, stay-green, peduncle exsertion, panicle length and width, plant height, days to flowering and maturity, grain yield, biomass and harvest index under drought stress and irrigated conditions. The results showed that genotypic differences were significant at P < 0.05 -< 0.001. High magnitude of phenotypic and genotypic coefficient of variations for plant height, harvest index and biomass as well as high heritability for days to flowering, panicle length, days to maturity and over all agronomic score were recorded. Principal component (PC) analysis showed that the first 4 PCs had Eigen value >1 explaining 74.6% of the total variation with grain yield, biomass, stay-green, leaf area, peduncle exsertion and days to flowering and maturity being the most important characters in PC1 and PC2. This research demonstrated high diversity for the characters studied. Moreover, the result showed that drought stress reduced the yield of some genotypes, though others were tolerant to drought. Accessions EG 885, EG 469, EG 481, EG 849, Hamelmalo, EG 836 and EG 711 were * Corresponding author.Tesfamichael et al. 1411identified as superior for post-flowering drought tolerance and could be used by breeders in improvement programs.

Drought stress occurring during the post-flowering growth stage of sorghum can cause considerable reduction in yield. In order to identify drought tolerant Eritrean sorghum landraces and assess efficiency of drought tolerance indices, twenty five sorghum (Sorghum bicolor L. Moench) accessions were evaluated in split plot design with three replications. Fully irrigated and drought stress treatments were assigned in main plot and the landraces were evaluated in sub plot for drought stress tolerance at post-flowering. Seven tolerance indices including stress tolerance index (STI), mean productivity (MP), geometric mean productivity (GMP), stress susceptibility index (SSI), tolerance index (TOL), yield index (YI), and yield stability index (YSI) were estimated for each genotype based on grain yield under drought stress (Y s) and irrigated conditions (Y ir). Significant correlations between Y ir and Y s with GMP, MP, STI and YI were recorded indicating that these indices were good predictors of drought tolerance among genotypes. The other stress tolerance indices namely, TOL, SSI, YSI and YI were not significantly correlated with Y ir and Y s indicating that they were poor predictors of drought tolerance. The study further showed that drought stress reduced the yield of some genotypes while others were tolerant to drought and gave stable yield. Based on the tolerance indices, accessions EG 885, EG 469, EG 481, EG 849, Hamelmalo, EG 836 and EG 711 were identified as superior genotypes for post-flowering drought tolerance that could be used by breeders in further sorghum improvement programs.

Diversity studies are an essential step in plant breeding and understanding the genetic relationships between pepper accessions may provide an effective management tool for their conservation, as well as help inform plant breeding efforts. The objective of the study was to assess the diversity and structure of pepper germplasm grown in Eritrean to help inform improvement programs. Local pepper (Capsicum spp.) germplasm collected from farmers and institutions in Eritrea was assessed using 16 quantitative morphological traits. The evaluation was conducted in two sites using a Randomized Complete Block Design with three replications. The data from the two sites were subjected to Principal Component Analysis, Hierarchal clustering with Euclidean distance and Analysis of variance. Cluster analysis of the combined data grouped the 60 genotypes into five clusters and 10 sub-clusters confirming the diversity of the collection that can be useful for selection and source of desired genes. A selection index was used to identify at least four promising genotypes (HD0134, HD0031 and NRSG21 and NRSAF06) for dry consumption purposes. The results of the current study revealed the relatively high level diversity existed within the evaluated collections and partitioned them into meaningful groups.

Diversity in plant genetic resources provides an opportunity for plant breeders to develop new and improved cultivars with desirable characteristics. The purpose of this study was to assess the diversity of Eritrean pepper germplasm in order to obtain information for improving it. A total of 60 pepper (Capsicum spp.) seed sample collections were obtained from farmers and institutions in Eritrea. The collections were evaluated at two sites located in two different agro-climatic regions of the country. The collections were assessed using 16 quantitative and 23 qualitative descriptors. A Randomized Complete Block Design was used for the evaluation. Quantitative and qualitative data of the two sites were subjected to Principal Component Analysis, Principal Coordinate Analysis, Hierarchal clustering, Analysis of variance and Correlation. The distribution of characters of the different quantitative and qualitative traits and the performance of the collections showed the existece of variable characters distributed among the collections indicating considerable diversity. For quantitative variables, the first three components were able to explain 61%, 58% and 67% of the total variation in Hamelmalo, Asmara and combined data of the two sites respectively. While for the qualitative variables the first three components were able to explain a variation of 58% in Hamelmalo, 49%, in Asmara and 55% combined data of the two sites. Phenological attributes and fruit characteristics were found to contribute more to the variation. The majority of the traits evaluated were significant and the highest Coefficient of Variation was related to fruit characteristics. The results of this study showed that there is sufficient variability within the Eritrean pepper genotypes that could be used in future breeding and crop improvement programs.

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