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There are seven species of genus Kniphofia in Ethiopian flora. K. foliosa, K. hildebrandtii, K. insignis, K. isoetifolia , and K. schimperi are endemic. Kniphofia pumila and K. thomsonii are widespread from West Africa to Eastern and Central Africa. In this study the genetic diversity and the relationships between five endemic and one widespread Kniphofia species in Ethiopia was conducted based on isoenzymes systems. The electrophoretic analyses of four enzymes systems in the species from ten experimental sites in ten locations revealed seven putative loci, of which PGM-1, PGM-2, AAT-2 and GPI-2 were polymorphic. The species have displayed higher genetic diversity parameters than other endemic plants. The over all mean inbreeding coefficient (F) was positive indicating slight deficiency in the number of heterozygotes. The total genetic diversity varies from 0.5 in K. schimperi to 1.11 in K. isoetifolia indicating very low diversification between the populations with in a species. At the generic level HT ranges from 0.034 to 0.470 with a mean of 0.247. The genetic variation among the species (G ST ) is 6.6%. Over all mean of genetic distance (0.011) and genetic similarity (0.938) indicated high similarity among the populations. Despite morphological variation particularly in floral morphology and inflorescence architecture, the over all mean of unbiased genetic identity of the species (0.989) is much higher than described for congeneric species (I = 0.64). The results, therefore, indicate that the Ethiopian Kniphofia species share a fairly recent common ancestor, but have differentiated in floral and inflorescence character through rapid evolution. This hypothesis needs, however, further testing. Key words/phrases : Endemism, genetic diversity, isoenzyme, kniphofia, inbreeding coefficient SINET: Ethiopian Journal of Science Vol. 27 (2) 2004:143–152

Variability of grass pea landrace populations for isozymes, Oxalyl Diamino Propanoic acid ODAP) and protein contents were investigated following standard procedures to detect genetic variation. The result indicated that phenotypic polymorphism was observed for the three enzymes, the highest being for esterase. The degree of differentiation (FST) of the individual loci ranged from 0.031 (for ACP-3) to 0.784 (for AAT-2). The highest polymorphism was detected in populations collected from Gondar region indicating the need for priority germplasm collection and site selection for in situ conservation in this region. The ODAP and protein analyses also revealed presence of variability among the populations. Fortunately, four entries with low ODAP contents ranging from 0.14% to 0.18% were identified in populations collected from different regions indicating the variation of this trait within population and between regions. These lines with low ODAP content are obviously considered important for further breeding program. Key words/phrases : Ethiopia, grass pea , isozyme, Lathyrus sativus , ODAP ET: Ethiopian Journal of Science Vol. 27 (2) 2004: 153–160

The study was conducted on 50 landrace populations of grass pea at Adet Research Center, Ethiopia, using randomised complete Block design in three replications to determine morphological variability and character associations. Evaluations were made on plant and yield characters from eight plants tagged randomly from each plot. The data were subjected to Analysis of Variance (anova), heritability, correlation and cluster analyses. Higher mean and cv values were recorded for most of the agronomic traits for populations collected from Gondar region and the higher altitude group (>2500 m) indicating the presence of high genetic diversity in this region and altitude group. Phenotypic coefficient of variation (pcv) was slightly higher than genotypic coefficient of variation (gcv) for all the characters studied signifying that genotypic factors exerted reasonable effect in estimating the variation. The wide difference between pcv (22.4%) and gcv (13.0%) for seed yield per plant indicated the complexity of this trait and the important role of other factors such as environment in influencing yield potential in addition to the genetic factors. The strong positive association of pods per plant, 100 seed weight and primary branches per plant with seed yield indicated the possibility of selecting lines for yield improvement based on these characters at the very early stage of the grass pea breeding program. Key words/phrases: Correlation grass pea, heritability, Lathyrus sativus, variation SINET: Ethiopian Journal of Science Vol.25(2) 2002: 191-204

The failure of faba bean production in some regions of Semien Shewa necessitated a research for a possible explanation and solution to reverse the problem. Two regions with a failure in pulse production of faba bean for five to ten years i.e.'yield-depleted' Molale and Mehal Meda, and two regions that are still capable of producing faba bean i.e. 'yield-sustained' Ankober and Keyt were selected. Comparative assessments of their nutritional factors, rhizobial type, rhizobial density, and inoculation and fertilizer treatments with respect to their soil types were undertaken. The soil analyses showed that 'yield-depleted' areas were generally characterized by a medium to high concentration of nitrogen (0.1—0.2%), a low content of phosphorus (3—6 ppm) and potassium, a high concentration of calcium and magnesium, and a lower population density of rhizobia (10 1—10 2 g-1 soil). The results also showed that shoot length, shoot dry matter, and nodule fresh weight were significantly affected (p=0.01) by soil type and different inoculation and fertilizer treatments. Although growth parameters, in general, were improved by different treatments, shoot dry matter and nitrogen contents were not significantly affected in 'yield-sustained' regions as compared to 'yield-depleted' ones. The results also showed that the comparative symbiotic effectiveness of the indigenous strains and the type exotic strain (reference strain) Tal 1397N was not different. It did not also show significant difference on the above mentioned growth parameters with different treatments. This indicates that the indigenous strains are equally effective in nitrogen accumulation provided that the problems of other limiting nutritional factors can be alleviated in the soil. This suggests that combined inoculation and fertilizer treatments can improve growth and reverse production of pulses in 'yield depleted' regions of Semien Shewa. SINET: Ethiopian Journal of Science Volume 24, No. 2 (December 2001), pp. 197-211 Key words/phrases: Faba bean, fertilizer and inoculation treatments, growth-related parameters, indigenous and exotic rhizobia, Semien Shewa