Zelalem Fisseha

The Ethiopian genetic center is a secondary center of genetic diversity for the common bean. This study was conducted to determine the genetic diversity and variability among Ethiopian common bean landrace accessions, using agro-morphological phenotypic traits. A germplasm sample of 121 landrace accessions was developed, which represented different common bean production ecologies and seed types common in the country. Released varieties 'Awash-1' and 'Melka-Dima', were used as Mesoamerican and Andean control genotypes, respectively. The sample accessions were grown at the main research station of Melkassa Agricultural Research Center, Adama, Ethiopia, during the main rainy season of 2016. Data were collected on 18 agro-morphological traits, including 10 standard morphological descriptors. Results showed that sample germplasm showed broad variability ranges with respect to important distinguishing qualitative (morphological) character traits considered, such as seed weight, shape, color, etc. Similarly, significant variability among the accessions were observed for five yield-related traits and seed yield, indicating there was adequate variability vis-à-vis these traits in common bean accessions from different parts of Ethiopia. To this end, both Tocher's and neighbor-joining clustering methods yielded five clusters from either of the two gene pools: Andean and Mesoamerican. D2 analysis showed the presence of significant inter-cluster distances. Finally, the first two principal component axes explained a substantial part of the variation (34%), with seven traits explaining most of the variation. This new information on phenotypic variability and genetic diversity improves our understanding of the organization of genetic diversity of Ethiopian common bean germplasm.

To explore the potential for in vitro rapid regeneration of Parkia timoriana, a multipurpose tree legume, cotyledon explants were cultured on MS and B5 basal media supplemented with various concentrations of 2,4-D, NAA and BAP. Successful callus induction was observed in all the treatments. Maximum percentage of callus induction was obtained in the 2,4-D supplemented basal media. However, the overall response of MS medium was found to be superior to that of B5 medium. Explants cultured on MS medium fortified with combinations of 2,4-D and BAP induced rapidly proliferating calli that turned more friable and nodular. These protuberances eventually developed into somatic embryos when transferred in basal MS suspension medium without growth regulators. The protocol described here is the first on P. timoriana and has the potential to produce plantlets through somatic embryogenesis and also offers a highly efficient method for mass clonal propagation and conservation for this multipurpose...

The Ethiopian genetic center is considered to be one of the secondary centers of diversity for the common bean. This study was conducted to characterize the distribution of genetic diversity between and within ecological/geographical regions of Ethiopia. A germplasm sample of 116 landrace accessions was developed, which represented different common bean production ecologies and seed types common in the country. This sample was then analyzed with 24 simple sequence repeat (SSR) markers to assess the genetic diversity within and between common bean landraces, classifying them based on SSR clustering, and determining relationships between genetic and agroecological diversity. Representatives of both Andean and Mesoamerican gene pools were identified by STRUCTURE software analysis, as well as a high proportion of hybrid accessions as evidenced by a STRUCTURE K = 2 preset. At the optimum K = 5 preset value, mixed membership of Andean and Mesoamerican genotypes in some of the clusters was...

Zelalem Fisseha1,*,
ABSTRACT: Twelve upland rice varieties, deemed NERICA (Oryza sativa
x O. glaberrima) were planted at three locations of the Somali Regional State
of Ethiopia in April 2010 with the objective of identifying the most stable
varieties and suitable stability models. Data were collected on eight yield and
yield-related phenological and agronomic traits. The analysis of variance
across locations for grain yield indicated that genotypic variations were
highly significant to significant in all locations. The combined analysis of
variance using Analysis of Variance (ANOVA) indicated that location,
genotype, and genotype x location (G x L) mean squares were highly
significant. The six stability models considered in the experiment (ANOVA,
Eberhart and Russell, Additive Main Effects and Multiplicative Interactions
(AMMI), Wricke’s ecovalence; Nassar and Hühn’s; and Shukla’s) identified
different genotype(s) to be the most stable ones. On the other hand,
comparison among the stability models using the criteria of Zobel et al.
(1988) and Spearman’s rank correlation coefficients indicated, AMMI and
Eberhart and Russell’s model outsmarted ANOVA and AMMI’s Interaction
Principal Component Axis (IPCA); Wricke’s ecovalence (Wi); Nassar and
Hühn’s absolute rank difference (S1); and Shukla’s stability variance (σi
2)
were in best correspondence with the ranking of the genotypes, respectively.
Key words/phrases: Correlation, Ecovalence, Genotypes, NERICA,
Stability models.