Genotype × Storage Environment Interaction and Stability of Potato Chip Color: Implications in Breeding for Cold Storage Chip Quality

potato (Solanum tuberosum L.) genotypes exhibit significant variation for chip color across different storage regimes. Lines that maintain light chip color after long postharvest storage durations and low storage temperatures are desirable to the potato industry. Since storage regimes vary among growers and processors, lines that exhibit stable chip performance across various storage regimes have a high probability of commercial success. The objective was to test if treating storage regimes as “environments,” analyzing genotype × storage environment interactions, and applying stability statistics can help identify desirable chip processing lines. To examine this, chip color of 47 breeding clones and six standard varieties was evaluated across eight storage environments. Chip color data was analyzed using stability metrics as well as stability-adjusted selection indices. The effects of genotype, storage environment, and genotype × environment on chip color were significant, explaining 47, 24, and 17% of total variance, respectively. Types I, II, and III stable lines were identified through stability analyses. Type I stability was significantly correlated with mean chip color. The most desirable lines were identified under long and cold storage environments. Using Type I stability and stability-adjusted indices, this study identified breeding clones for advancement, including W5840-4, W64845, and W6929-1, which outperformed standard chipping varieties for chip quality and stability. Dep. of Horticulture, Univ. of Wisconsin-Madison, 1575 Linden Drive, Madison, WI 53706. Received 6 Feb. 2013. *Corresponding author ([email protected]). Abbreviations: AMMI, additive main effect and multiplicative interaction; bi, Eberhart and Russell’s regression coefficient; G×E, genotype × environment; HARS, Hancock Agricultural Research Station; PC, principal component; Pi, superiority of the ith line; RARS, Rhinelander Agricultural Research Station; sdi, line i’s deviation from regression; si, line i’s mean sum of squares of departure from regressions; si, Shukla’s stability variance; YSi, Kang’s selection index. Published in Crop Sci. 53:1944–1952 (2013). doi: 10.2135/cropsci2013.02.0089 © Crop Science Society of America | 5585 Guilford Rd., Madison, WI 53711 USA All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Permission for printing and for reprinting the material contained herein has been obtained by the publisher.