Eco-physiological yield determinants in four potato genotypes grown in a temperate environment

Abstract

The eco-physiological yield determinants of four potato genotypes suitable for processing into French fries were studied. Field trials were carried out during the growing seasons 2016/17 and 2017/18 at Balcarce, Argentina (−37.85 S, −58.19 W). Genotypes, identified as Bal1, Bal2, Bal3 and Bal4, have growing cycles of 95–105, 100–110, 110–120, and 120–130 days after emergence, respectively. Intercepted photosynthetic active radiation (PARint), radiation use efficiency (RUE), harvest index (HI) and tuber yield were evaluated during both growing seasons. Bal4 achieved the highest dry matter tuber yield in both growing seasons, with 1412 and 1879 g mˉ² for 2016/17 and 2017/18, respectively. Due to a combination of a high PARint and RUE values, tuber dry matter in Bal4 was 20–30 % higher than that achieved by other genotypes. PARint throughout the growing cycle was 1025 and 1121 MJ mˉ² for Bal4, for 2016/17 and 2017/18 seasons, respectively; these values were 10–22 % higher than those observed for the other genotypes. RUE was 1.66 and 2.02 g MJˉ1 for Bal4 in 2016/17 and 2017/18 growing seasons, respectively, these values are 14–18 % higher than those observed for the other genotypes. HI varied between 0.81 and 0.87 for all genotypes, in both seasons. PARint, and RUE were the two most critical yield determining factors that explained the differences in tuber dry matter yield between the potato genotypes. Bal4 showed highest yields due to a particular combination of high PARint and high RUE, not reported in the literature, so far. These results could contribute to improve early selection in future breeding programs, to better adjust growth models and to establish specific management strategies for a particular genotype.