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Rice is among the most important commercial cereal crops that can be produced in North Gondar. However, its production is challenged by low yield mainly due to lack of appropriate agronomic practices and recommendations. Uses of appropriate seed rate and row spacing most importantly affect the productivity of rice. Therefore, a field experiment was conducted to investigate the effects of seed rate and row spacing on grain yield and yield components of upland rice. Factorial combinations of four seed rates (60, 80,100 and 120 kg ha-1) and three levels of row spacing (20, 25 and 30 cm) were laid out in RCBD with three replications using NERICA-4 rice variety. The combine interaction effect of seed rate and row spacing was highly significant (P<0.01) on days to heading, days to maturity, number of total tiller per meter row length, thousand seed weight and grain yield, and significant (P<0.05) on plant height. The highest thousand seed weight (27.3 g) was recorded at seeding rate (80 kg ha-1 and grow spacing of 30 cm but the lowest (17.1 g) was recorded on seed rate of 120 kg ha-1 and row spacing of 25 cm. The highest grain yield (4148.8 kg ha-1) was obtained at interaction of 80 kg ha-1 seed rate and 20cm row spacing. While the lowest grains yield (1826.4 kg ha-1) was obtained from the combination of 60 kg ha-1 seed rate and 30cm row spacing. In conclusion, the results revealed that seed rate and row spacing increased grain yield of rice by positively affecting the important yield components of the rice. The result of economic analysis showed that the maximum net benefit was obtained at seed rate of 80 kg ha-1 and row spacing of 20 cm. Hence use of 80 kg ha-1 and 20 cm is promising for upland rice variety production under the rain fed condition at Metema district and similar agro ecologies.

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Twelve Ethiopian caraway genotypes were evaluated in eight environments in Ethiopia during 2014 and 2015 under rain fed condition. The field experiment was laid out using randomized complete block design with three replications. The objective of this experiment was to select high yielding and stable Ethiopian caraway genotypes with nonparametric methods. Combined analysis of variance was performed and 10 rankbased nonparametric stability parameters were measured. A pooled analysis variance for seed yield indicated that there were highly significant (P < 0.001) differences for main effects of genotype, environment, and their interaction. Genotype Gondar 027-2001 gave maximum number of umbel per plant. However genotype Gondar 010-2002 was recorded lowest number of umbel per plant. Adet 12-2000 gave highest plant height (64.7 cm) while Gondar 026-2000 gave lowest plant height (56.7 cm). A wide range variation was observed in days to flowering varied 87.7-91.8, days to maturity varied 157. 16-159.8, plant height 56.7-64.7. The results of principal component analysis revealed that the stability statistics and yield were classified into three groups and related to two contrasting concept of stability. In this study, TOP and rank-sum were found to be

Twelve Ethiopian caraway genotypes were evaluated in eight environments in Ethiopia during 2014 and 2015 under rain fed condition. The field experiment was laid out using randomized complete block design with three replications. The objective of this experiment was to select high yielding and stable Ethiopian caraway genotypes with nonparametric methods. Combined analysis of variance was performed and ten rank-based nonparametric stability parameters were measured. A pooled analysis variance for seed yield indicated that there were highly significant (P<0.001) differences for main effects of genotype, environment and their interaction. The results of principal component analysis revealed that the stability statistics and yield were classified into three groups and related to two contrasting concept of stability. In this study, TOP and rank-sum were found to be useful measures for simultaneously selecting high yield and stable cultivars. These measures selected Gondar 027-2001 and Gondar 023-2000 that gave 2254.7 Kg ha-1 and 2186.1 Kg ha-1 seed yield respectively, as stable and the National Variety Release Committee has released these genotypes as the first Ethiopian caraway varieties for production in 2017.