Effect of planting density on growth, light interception and tuber yields of potato varieties (Solanum tuberosum l.) at Guji highland of southeastern Ethiopia

Abstract

Planting density is important agronomic management tool for potatoes as it determines light interception, growth, yield and yield components of the crop. However, the information at spasfic location is limited. Thus, the experiment was conducted to determine the optimum plating density for potato varieties and its impact on growth, light interception, yield and yield components. A field experiment was conducted at Bore in the southeastern Ethiopia during the 2021 cropping season. The experiment consists of four levels of planting densities (66667, 44444, 33333 and 26667 plant ha-1) and four potato varieties: three improved (Jalanie, Gudenie, Belete and one local (Gujicha) that were laid out in a randomized complete block design (RCBD) in factorial arrangements with three replications. The result indicated that the main effects of variety and planting density significantly (p < 0.001) influenced days to 50%
flowering, 90% maturity date, plant height, number of stems per hill, leaf area index (LAI) at 45, 60 and 75, Cumulative Interception Photosynthetic Active Radiation (CIPAR) and total dry matter production. However, tuber yield, tuber weight, average tuber number per hill, marketable yield and total tuber yield were significantly affected by the interaction effects. The overall result indicated that CIPAR increased with increasing planting density, though a maximum marketable tuber yield of 44.92 t ha-1 was recorded at 444444 plant ha-1 from Gudenie variety. However, the CIPAR was not fit with the maximum marketable and total yield of tuber; this indicates other plant and environmental factors might also significant for plants to express their yielding potential.