Stability of eight potato genotypes for sugar content and French fry quality at harvest and after storage

Abstract

Affleck, I., Sullivan, J. A., Tarn, R. and Yada, R. 2012. Stability of eight potato genotypes for sugar content and French fry quality at harvest and after storage. Can. J. Plant Sci. 92: 87–96. Processing quality of potatoes for French fries is partially determined by reducing sugar content of the tuber. Much of the potato crop is processed after a storage period when sugar content can change and affect processing quality. In this study, the stability of sugar levels in eight potato genotypes was studied over four environments (i.e., two locations over 2 yr). The GGE biplot analysis was used to measure the stability of, and the association between, quality traits and sugar content. Quality and sugar content were measured 105 and 120 d after planting and 60 and 120 d after storage. The biplots indicated a change in French fry colour scores and stability between the 105 and 120 d after planting harvest dates. Genotypic differences were noted for French fry colour scores and glucose content. Genotypes were identified that were stable for French fry colour during the two storage periods indicating low genotype by environment interaction. The GGE biplot identified mega-environments that encompassed a group of environments with similar attributes. Based on this finding potatoes from only one environment within the mega-environment would need to be stored for quality evaluations.