Genetic parameters and responses associated with high temperature in potato wild relatives.

Abstract Crop wild relatives (CWRs) have significantly been used in potato ( Solanum tuberosum , Solanaceae) breeding. Hence, introgression breeding may help in coping with the challenges posed by climate change. We used 20 accessions from Embrapa Potato Genebank, twelve belongs to wild specie Solanum chacoense and eight from S. commersonii and one, S. tuberosum commercial cultivar for their tolerance to two different temperature conditions CT as control temperature (14–24ºC) and HS as heat stress (24–37ºC). The evaluation was based on gas exchange (Pn, Gs and Tr), chlorophyll fluorescence analysis (Y(II), NPQ, Fv/Fm), chlorophyll A, B and carotenoid content and tuber yield related traits (FTW and DMC%) and measured after 1DAS (Days after stress), 15DAS and 35DAS. Mixed model methodologies were used to predict average genotypic value in the various environments and capitalize on an average interaction with all evaluated environments. Significant differences were observed between Solanum wild genotypes showed by 2-factorial for agronomic traits and 3-factorial ANOVA for physiological traits. The correlations among the accessed traits were found here significant for heat stress conditions. Mixed model methodology helps us ranking the genotypes based on measured variables according to their true genotypic values for both temperature conditions and after each measurement of days after applied stress.