Stability of potato clones resistant to potato virus Y under subtropical conditions

Brazilian potato production is based on cultivars originating from the USA and Europe; however, these cultivars were developed under different environmental conditions than those found in Brazil. The aim of this study was to evaluate the adaptability and stability of 18 potato clones (MLG), developed by the Universidade Federal de Lavras, and four cultivars in six environments in the state of Minas Gerais, Brazil. The following traits were evaluated: marketable tuber yield (MTY), specific gravity (SG), and tuber appearance (TA). Clones, environments, and the genotype x environment interaction had significant effects on all traits. The GGE-biplot explained 71.78, 98.13, and 62.86 % of the sum of squares from the G+GxE for MTY, SG, and TA, respectively. Three MLG clones had higher adaptability and stability, as well as better performance, than the cultivars, making them good candidates for release as cultivars.