Index‐based selection of potato (Solanum tuberosum L.) genotypes for tolerance to soil moisture and ambient heat stress

Abstract

Developing potato varieties that have enhanced tolerance to soil moisture and high temperature stress could improve household food and nutrition security in drought and heat prone areas. A field experiment was conducted at two locations in Ethiopia to evaluate the effectiveness of some stress tolerance indices for the identification of drought and heat tolerant potato genotypes. Treatments consisted of three irrigation regimes and 23 potato genotypes. The experiment was laid out as a split‐plot design in a factorial arrangement with three replications. Irrigation regimes were the main plot factor and genotypes were the sub‐plot factor. Stress tolerance indices were calculated based on the tuber yield under stress (Ys) and non‐stress (Yp) conditions of each genotype. To determine the most desirable stress tolerant genotypes, all indices mean rank (R) and standard deviation of the R were computed. Genotypes Cl‐12(CIP‐304371.67), Cl‐13(CIP‐304383.80), Cl‐2(CIP‐302499.30), Cl‐34(CIP‐397079.6), Cl‐15(CIP‐304394.56) and Cl‐14(CIP‐304387.39) were found to have had top mean ranks and higher tuber yield under drought and heat stress. Ranking methods using all indices best determined desirable drought, heat and combined drought‐heat tolerant genotypes that consistently coincided with the yield rank of genotypes under a given stress condition. This implies that these indices (STI, GMP, MP, YSI and TOI) could be used in combination to differentiate stress tolerances and susceptible potato genotypes. It is recommended that genotypes that exhibited higher drought and/or heat stress tolerance in this study could be further evaluated in drought and heat prone areas for the development of tolerant potato varieties.This article is protected by copyright. All rights reserved

Harnessing potato and sweetpotato innovations for resilient and healthier agri‐food systems in Africa

“…The two papers on potato breeding present progress in selection of genotypes for further investigation. In Ethiopia (Gelmesa et al, 2024), an index-based selection procedure was employed to advance six of 23 genotypes demonstrating enhanced tolerance to soil moisture and elevated temperature stress. In Rwanda (Rukundo et al, 2024), 10 of 37 high-iron, high-zinc biofortified potato clones were selected for advancement as the country seeks to release its first biofortified potato varieties.…”