Arabica coffee is the predominant commodity in contributing for foreign exchange in Ethiopia and improvement for yield and other desirable traits is highly momentous. Estimating genetic diversity is a prerequisite activity in plant breeding program for crop improvement. This study was designed to determine the extent of genetic variability among Wollega coffee landrace and importance of gene revealed in traits. The 26 genotypes were tested during the 2016/2017 cropping season at Mugi and Haru sub-enters using RCBD. The combined analysis manifested significant difference among genotypes only in node number per primary branch (NNPB), fruit traits and Coffee leaf rust (CLR) although significant difference recorded for 18 and 22 of the 23 traits at Haru and at Mugi, respectively. The difference between environments was significant for all traits, except for CLR, yield (YLD), leaf, some fruit and bean traits. Performance at Haru was less than at Mugi for all traits showed significant difference. Genotype x environment (GEI) was significant for all traits excluding NNPB, leaf length (LL), fruit width and CLR indicating inconsistency performance of Coffee genotypes. At Haru, high phenotypic coefficient of variation (PCV>20%) recorded for YLD (25.5%), CLR (110.0%) and number of secondary branch (NSB) (22.0%), but High genotypic coefficient of variation (GCV>20%) recorded only for CLR (99.6%). At Mugi, High PCV and GCV (>20%) recorded for YLD (38.6%) and CLR (98.4%). Heritability ranged from 10.0% (YLD) to 88.0% (BW) while genetic advance (GAM) ranged from 1.5% (LL) to 32.4% (NSB) at Haru. At Mugi, Heritability ranged between 31% (CLR) and 84.0% (bean thickness) and between 3.3% (LL) and 44.0% (YLD) for GAM. The present results elucidate the existence of moderate genetic diversity among genotypes for some traits at individual location indicating the possibility of improvement for desired traits via selection. For further diversity analysis, molecular characterization methods need to be carried out.

Coffea arabica L., the dominant cash crop in the world market, is native to rain forest of Ethiopia where it is believed to exist with high genetic diversity. Estimating genetic parameters are momentous in deciding breeding method to be followed for crop genetic improvement including Arabica coffee. The study was conducted with the intention to gauge genetic gain trend in coffee yield and to select advanced promising lines of Yayo coffee landrace for the next breeding step. The study was laid down at Metu research subcenter in 2013, using 124 coffee accessions that were established in simple lattice design under two sets each comprising 62 accessions including two checks. The over six year’s pooled analysis of variance indicated the handiness variability in yield performance among accessions. Moderate genotypic variance (15.46 to13.56%), heritability (56.16–81%), and expected genetic gain (15.52–20.8%) were observed. The genetic parameters and the superiority of check in yield over accessions elucidated that high yielder variety development by selection is difficult unless heterosis attaining breeding method followed, particularly for these Yayo coffee landrace origin. Common high genetic gain trend (49.19 and 100 kg·ha−1) and response to selection (196.76 and 400 kg·ha−1), selection differential 471.9 and 739.23 kg·ha−1 were revealed in over four harvesting seasons mean value for both sets. Thus, selection is more effective in earlier season than late. High yielding accessions, Y27 and Y93, gave 3013.1 and 125.8 kg·ha−1 yield gain over the high yielder check correspondingly. Despite the top 15 and 10 high yielders were selected from set-I and set-II, respectively, a total of 20 accessions with contrasting desirable traits were selected and established in crossing block for genetic improvement purposes via heterotic hybrid variety development program. These accessions were tolerant to major coffee disease and have desirable agronomic traits.

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Genetic factor is a key factor to realize optimum growth and dry matter production of crops in addition to environmental factors. Haricot beans (Phaseolus vulgaris L.) cultivar type is important for good agronomic performance for greater production of dry matter and grain yield. The present study was conducted with objectives to estimate the performance of haricot bean cultivars based on dry biomass and growth traits and to observe the impact of different growth stage on various growth characteristics of haricot bean cultivars. Three haricot bean cultivars were evaluated using RCB design with three replications at Hawassa University Agricultural College, Southern Ethiopia during off season from November 2016 up to January 2017. Collected data were specific leaf area ratio (SLA), leaf area ratio (LAR), net assimilation rate (NAR), relative growth rate (RGR), leaf area and above ground biomass. Dissimilarities have been observed in LAR, SLA, NAR and RGR among cultivars. But there was no significant difference observed among cultivars for total biomass. The LAR and SLA of all cultivars declined as crop development advanced. So, it is fair to say that these haricot bean varieties perform differently across their growing period. The NAR during early development was 41.3 mg/dm2/day as maximum value. Generally, the current field study elucidates the interdependence of some characters and the existence of difference among haricot bean cultivars for some growth characteristics indicating cultivar difference in morphological characters which may have influence on physiological characters.

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