A field study consisting of fourteen sorghum genotypes was conducted to determine turcicum leaf blight (TLB) intensity, resistant reactions, and agronomic performance of sorghum genotypes at Arba Minch and Derashe, southern Ethiopia. The study was carried out during the 2018 cropping year (March to July). A significant (P < 0.05 to < 0.0001) variations were observed in the magnitude of TLB intensity, resistant reactions and agronomic parameters among the evaluated sorghum genotypes as well as locations. The results indicated broad ranges of difference in disease progress rate with 0.0138 (Seredo) to 0.0392 (Rara) units day-1 at Arba Minch and 0.0138 (Kentera) to 0.0392 (Rara) units day-1 at Derashe were observed on the evaluated genotypes. The results also showed wide ranges of variations in incidence (71.15–83.51%) on average for the two locations. The highest mean severity (59.80 and 83.60%) and area under the disease progress curve (AUDPC) (988.65 and 1261.38%-days) were noticed from genotype Rara at Arba Minch and Derashe, respectively. The lowest mean severity and AUDPC were noted from genotype Gambella with 7.97 and 13.64% and 132.66 and 214.84%-days at Arba Minch and Derashe, respectively. Based on TLB mean severity score, sorghum genotypes were categorized as 42 and 29% resistant, 35 and 35% moderately resistant, and 23 and 28% susceptible at Arba Minch and Derashe, respectively. In addition, significant genotypic differences were observed for crop phenology, growth, yield, and yield-related parameters. The genotypes, 76TI#23 (4444.44 kg ha-1) and Melkam (4444.44 kg ha-1) (at Arba Minch) and Dekeba (1333.33 kg ha-1) (at Derashe) showed the highest grain yields as compared to the other genotypes in the two locations. Various association degrees were observed between disease scores and crop parameters. Overall results pointed out that genotypes such as 76TI#23, Meko-1, Seredo, and Gambella-1107 exhibited consistent resistance reaction to TLB, although they showed variable grain yield potential across the locations. The genotype 76TI#23 is suggested to the producers with appropriate field management practices for sorghum production, and Gambella-1107, Seredo, 76TI#23, and Meko-1 used as a source of parental material for TLB resistance development in a future breeding program.

Six white fleshed sweet potato varieties were tested in Gamo zone of southern region, Ethiopia in 2019 and 2020 to evaluate their total root yield potential and demonstrate best performing varieties. The experiment was laid out as a Randomized Complete Block Design with four replications. The combined analysis of variance showed highly significant differences among genotypes on growth, root yield and its components. The maximum number of marketable roots per plot was recorded on variety Hawassa -09 (70.25) whereas minimum number of roots per plot was recorded on ADU (11.00). The highest root yield per hectare was obtained from variety Hawassa -09 (62.16 ton ha-1) followed by Tola and Berkume (53.99 and 52.85 ton ha-1), respectively. The lowest root yield per hectare was recorded from variety ADU (5.21 ton ha-1). Based on the result of this study from six evaluated white fleshed sweet potato varieties Hawassa -09 was recommended for pre extension demonstration at the area and similar agro ecological locations.

Anthracnose disease caused by Colletotrichum sublineolum is a major constraint that limits the production and productivity of sorghum in Ethiopia as well as in other countries. This study was carried out at Arba Minch and Derashe districts during the 2018 cropping season, March to August. The objective of the study was to identify the host resistance for anthracnose management and estimate the genetic variability in terms of resistance to anthracnose, growth, and yield potentials of sorghum. The treatments used in the study were 14 sorghum genotypes and laid in a randomized complete block design with three replications. The results from this study showed that Arghiti, Dekeba, and 76TI#23 were found resistant, while Kolamulato-W, Konso-R, Gambella, and Seredo were highly susceptible to anthracnose. The lowest (0.25 t ha-1) grain yield was recorded from all landraces, whereas the highest (3.22 t ha-1) grain yield was obtained from the genotype Melkam. The high phenotypic and genotypic variances were figured out for the study parameters, while the environmental variance was lower than the genotypic and phenotypic variances. Low to high genotypic (21.40 to 57.94%) and phenotypic (22.66 to 95.21%) coefficients of variations were computed for the study parameters. The high heritability of 59.30 to 99.63% and the genetic advance in percent means of 20.21 to 63.10% were calculated for the study parameters. The disease parameters, like disease severity and area under disease progress curve (AUDPC) (rg = 0.725), showed a strong and positive association of genotypic coefficients correlations. Also, strong and negative genotypic coefficients of correlations were observed between the disease and traits studied, like AUDPC and grain yield (rg = -0.561). The dendrogram of the sorghum genotypes using the Unweighted Pair-Group Method with Arithmetic means analysis and Euclidean distances separated the genotypes into three clusters. The result from this study revealed that the sorghum genotypes noticeably varied in resistance to anthracnose as well as growth and yield potential. Therefore, sorghum producers could beneficially produce resistant, moderately resistant, and high-yielding genotypes with minimum integrated management efforts against the anthracnose. Moreover, the genetic variability and the high heritability together with, and the high genetic gain of the characters, suggest the potential of bettering the genotype for disease resistance and high yield potential through selection.

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