Effect of soil moisture deficit on marketable yield and quality of potatoes.

Abstract

Tuber yield and quality are the two main factors that can increase or decrease the market value of potatoes. Soil moisture availability and nutrient concentration within the potato root zone play a pivotal role in controlling tuber yield and quality. This study was conducted in Southern Manitoba to compare the effects of overhead irrigation (IR) and no-irrigation (NI) on marketable tuber yield and quality during the 2013- and 2014-growing seasons. The total yield of potato was not significantly different between the two treatments in both years. In 2013, the marketable yield of the irrigated (IR) treatment (36.89 MT/ha) was 20% higher (p = 0.017) compared to the non-irrigated (NI) treatment (30.74 MT/ha). However, no significant difference in marketable yield was found between the irrigated (39.0 MT/ha) and non-irrigated (43.7 MT/ha) treatments in 2014. Excess nitrate accumulation within the root zone tends to promote the formation of over-sized tubers. Although the incidence of hollow hearts and sugar ends showed a higher trend in the non-irrigated treatment it was statistically not significantly different from the irrigated treatment. Overhead irrigation was found to be economically advantageous to produce better quality potatoes with higher marketable yields.