REGULAR ARTICLE Evaluation of yield response of second early edible potato cultivars to spatial environmental conditions Katarzyna Rymuza 1 *, Tomasz Lenartowicz 2 , Elżbieta Radzka 1 , Antoni Bombik 1 1 University of Natural Sciences and Humanities in Siedlce, Prusa 14, 08-110 Siedlce, Poland. 2 The Research Centre for Cultivar Testing in Słupia Wielka, 63-022 Słupia Wielka, Poland. *Corresponding author: Katarzyna Rymuza; E-mail: katarzyna.rymuza@uph.edu.pl CITATION: Rymuza K., Lenartowicz T., Radzka E., Bombik A. (2015). Evaluation of yield response of second early edible potato cultivars to spatial environmental conditions. Communications in Biometry and Crop Science 10, 27–40. Received: 22 October 2014, Accepted: 21 April 2015, Published online: 13 May 2015 © CBCS 2015 ABSTRACT Analyses were performed on a tuber yield dataset consisting of yield data for 14 second early edible potato cultivars, obtained from a series of multi-year (2010-2013), multi-location PDO (post-registration variety testing) experiments. The trials were conducted at 6 experimental stations at the Research Centre for Cultivar Testing (COBORU) in Słupia Wielka (Poland). The objective of this work was to evaluate the response of potato cultivars to diverse environmental conditions in Poland, taking into account total precipitation and mean air temperature during the growing season. The analyses demonstrated that there was a significant interaction between cultivars and years as well as between cultivars, years, and locations. On the contrary, the ‘cultivar x location’ interaction was not significant. The structures of both the significant interactions were analysed using mixed multidimensional and joint regression models. The cultivars Ametyst and Bogatka did not interact with the environment, but only the first cultivar was considered stable. All the remaining cultivars significantly interacted with the environment, in particular Finezja and Oberon, which responded significantly to environmental conditions during the growing season. Key Words: genotype-by-environment interaction; multi-environment experiments; yield stability; potato cultivar. INTRODUCTION Edible potato is a major crop worldwide due to its versatility and role in human nutrition (Cotes et al. 2002, Sadowska et al. 2004, Hassanpanah and Azimi 2010). Potato tubers may be consumed directly or after processing. Depending on how they are used, potato cultivars should possess certain qualitative characteristics and produce high and stable yields. Yield performance of a crop is affected by the cultivar (genotype) and environmental conditions, as well as by crop management systems (Cotes et al. 2002, Kołodziejczyk 2013). HTTP://AGROBIOL.SGGW.WAW.PL/CBCS COMMUNICATIONS IN BIOMETRY AND CROP SCIENCE VOL. 10, NO. 1, 2015, PP. 27–40 INTERNATIONAL JOURNAL OF THE FACULTY OF AGRICULTURE AND BIOLOGY, WARSAW UNIVERSITY OF LIFE SCIENCES – SGGW, POLAND