Multitrait differential response in a diverse potato panel under contrasting water regimes

Abstract

Water stress is the most significant environmental stress in agriculture worldwide. Potato (Solanum tuberosum L.) is a drought-susceptible crop. Water stress tolerance is a complex trait of increasing importance in potato. The objective of this work was to evaluate the differential response strategies associated with water stress tolerance in a highly diverse potato panel. Multienvironment trials were assessed, both in field and in glasshouse with contrasting water regimes. The yield, dry matter, and frying ability were measured in the field assays, whereas proline concentration (PrC), relative water content (RWC), and water consumption (WC) were measured in the glasshouse assays. A mixed linear model and ANOVA were performed. The best linear unbiased predictors (BLUPs) of every genotype for each measured variable were estimated. Pearson correlation coefficient (r) and principal component analysis (PCA) assessed the association among traits. The genotypes were ranked by their BLUPs values. The high diversity potato panel showed variability both in the response to water stress and within each water regime. In general, Solanum tuberosum spp. andigena genotypes were associated with the lowest PrC and higher yield, WC, and RWC. By using BLUPs, a panel of genotypes with good performance under water deficit was defined. This paper provides knowledge useful to design breeding strategies to water stress tolerance and new physiological research lines. The utilization of the elite genotypes identified in this study as progenitors constitute a starting point for breeding programs oriented to develop water-stress-tolerant varieties.