Abstract:
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.
