Cold Tolerance in Sugarcane Progenies Under Natural Stress

Cold stress reduces crop yields and quality, limiting agricultural expansion. The objective of this study was to evaluate cold tolerance in sugarcane (Saccharum spp.) progenies based on physiological and biometric characteristics under natural cold stress. The experiment was carried out at a station of the Temperate Climate Research Center, of the Brazilian Agricultural Research Corporation (Embrapa), in Pelotas, Rio Grande do Sul, where 21 full-sib sugarcane progenies were evaluated in an incomplete block design with six replications. Physiological and biometric characteristics were measured after frost events to determine cold tolerance. The components of variance, genetic parameters and correlations were estimated using mixed models (REML/BLUP). The meteorological data recorded on-site showed the occurrence of 13 frost events (0 °C) and a minimum temperature of − 2.9 °C. Genetic variability for cold tolerance was detected between and within progenies. Narrow-sense heritability was moderate for chlorophyll content (0.23), leaf damage (0.26), stalk damage (0.19) and total soluble solids content (0.44), while heritability at the progeny level was high for all traits (> 0.57). The genotypic values for cold tolerance and yield potential were highest in the progenies RB996962 × RB016916, RB016916 × RB996962, RB867515 × RB92579 and RB106802 × RB036088.