Potato is an increasingly important crop in Ethiopia. The Gamo Highlands are one of the large potential potato producing regions in Ethiopia. The growing conditions are different from those in the temperate regions, where most of the agronomical expertise on potato has been developed. The influence of environmental conditions on the crop in the Gamo Highlands is poorly understood. We conducted field trials with eight potato cultivars in six locations and during two seasons. The canopy cover (CC) and plant height (PH) were measured with high temporal resolution and tuber yields were assessed as well. The experiments were conducted near our newly installed weather stations at different elevations. CC and PH were strongly correlated with temperature sum (Tsum). Tuber yields differed among elevations and cultivars. Nevertheless, these differences were poorly explained by environmental variables. We also found that no single cultivar performed best at all elevations. The number of branches was a predictor of yield, suggesting that radiation interception was limiting tuber growth. Tuber yield was optimal when the number of days to crop maturity was around 100–110 days. We conclude that Tsum is a predictor of crop growth, but environmental variables poorly explain yield variations, which calls for further investigation.

In Minda et al. [1], an error was introduced. We propose the following amendment: Figure 9, inSection 3.2.4 (Days to Maturity and Yield), should be replaced by the following updated figure [...]

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.

The study was conducted at Chencha in Southern Ethiopia during the 2018 and 2019 main cropping years to determine the effects of planting dates and potato genotypes on late blight epidemics and yields related traits; as well as identify optimum planting date and potato genotypes which show low levels of late blight severity with high tuber yields under a natural epiphytotic environment. The treatments composed of four potato genotypes (Belete, Gudenie, Jalenie, and local check) and three planting dates (on 10th June, 10th July, and 20th August). The experiment was laid out in a split-plot design with four replications. Planting dates were assigned as the main factor, while the potato genotypes were represented as a sub-plot factor. Average late blight severities of 29.19, 35.82, and 44.70% were recorded on plants with a planting date of 20th August, 10th July, and 10th June, respectively. Foliar late blight severities of 27.31, 32.45, 38.58, and 47.95% were recorded on Belete, Gudanie, Jalenie, and local cultivar, respectively. Similarly, the relative area under disease progress curve (AUDPC) of 20.28, 24.93, and 29.31%-days were recorded on planting dates of 20th August, 10th July, and 10th June, respectively. The highest (19.37%-days) and lowest (31.32%-days) values of AUDPC were recorded from the genotypes Belete and local cultivar, respectively. Results also showed that the highest single tuber weight (87.20 g) and total tuber yield (13.40 t ha-1) were obtained from the genotype Gudenie. Regarding planting dates, the highest single tuber weight (88.91 g) was recorded from the genotypes planted on 10th June. Whereas the highest total tuber yield (15.77 t ha-1) was obtained from the genotypes planted on 20th August, which was not statistically different from the other planting dates. Overall, considering disease development, tuber yield potential, and effectiveness in disease reduction, planting of Gudenie on 20th August was relatively effective for potato late blight management as compared to other genotypes and planting dates. Therefore, this could be suggested for the study area and similar agro-ecological conditions to enhance sustainable potato production.