Donors of potato (Solanum L.) plasticity and yield stability traits in the environmental conditions of north forest steppe of Western Siberia

Potato ( Solanum tuberosum L.) varieties possessing sustainable high yield under varying environmental conditions and other valuable properties, e.g. resistance to diseases and pests, are much appreciated by practitioners. Seeking for donor plants with high environmental plasticity and stability in specific cultivation zone is a key point, especially in creating highly productive adaptive varieties for regions with severe agro-climatic conditions. This paper reports the first assessment of new potato hybrids created in the soil and climatic conditions of Western Siberia, as donors of high yielding and complex relative resistance to fungal diseases, potato Y-virus, and golden potato nematode. The best of them are already involved in practical selection for productivity and high adaptability. Our goal was to assess the parameters of adaptability in created potato hybrids under the conditions of the northern forest-steppe of Western Siberia (Kuznetsk Basin, Kemerovo Region, Kemerovo District, 2014-2018; 70 m2 plots with 20 m2 test area arranged randomly in four repetitions). Planting was carried out in the third decade of May at 35.0 thousand bushes per 1 ha (70×35 cm; a Cramer potato planter, CRAMER Technik, Germany). The samples ( n = 170) including collection potato hybrids created in Kemerovo Research Institute of Agriculture were examined in a collection nursery. The varieties Lyubava (early season), Nevskii (medium-early ripening) and Tuleevskii (medium-ripening) were the standard. According to our research data, the Lyubava, Nevskii, Tuleevskii varieties and hybrids 6-4-11 and 22103-10 are extensive type potato genotypes with low environmental plasticity (bi = 0.28-0.91 i = 1.53) with medium yield stability (Si2 = 14.6) showes the greatest response to external conditions. Hybrids 22103-10 and 3-21c-11 are donors of resistance to potato virus Y (gene Ryсhc ), golden potato nematode Globodera rostochiensis (Woll.) (gene H1 ) and pale nematode G. pallida (Stone) Behrens. (gene Gpa2 ). According to a complex of the traits, three hybrids of the intensive type (17-5/6-11, 1-5-12 and 1615-10) possess high adaptiveness, i.e. an increased environmental plasticity (bi = 1.38, 1.20, and 1.17) and high stability (Si2 = 1.1, 9.4, 5.2), and are of particular value for breeding. Moreover, the hybrid 17-5/6-11 is a donor of resistance genes to potato virus Y (PVY) ( Ryсhc ) and golden potato nematode ( H1 , with three markers - TG689, 57R, and N195). Hybrid 1-5-12 contains a combination of the H1 genes (for all three markers) and Gro1-4 gene of resistance to G. rostochiensis , Gpa2 gene of resistance to G. pallida , and genes Rychc and Rysto conferring resistance to PVY. Long-term field surveys of resistance to fungal pathogens, Phytophthora infestans (Mont.) De Bary, Alternaria solani (Ell.Et Matr) Sor., Fusarium oxysporum Schlet., Rhizoctonia solani J.G. Kühn) and Actinomyces scabies Gussow showed a 7-9 point relative stability in all tested hybrids.