Use of Comparative Transcriptomic Analysis of Different Potato Varieties to Elucidate the Molecular Mechanism Underlying Differences in Cold Resistance

Abstract

\n Background\n\nAmong the various abiotic stresses, cold is an essential factor that limits crop productivity worldwide. Low temperature affects the growth, development and distribution of agronomic species around the world. To improve the understanding of the physiological and genetic properties and functions affecting potato cold tolerance, in this study, transcriptomic analysis was performed on two potato strains (HZ88 and LS6) with different cold tolerances that were treated at low temperature for 0, 1, 3, and 6 hours.\nResults\n\nTranscriptomic analysis showed that there were large differences between HZ88 and LS6 regarding the expression levels of low-temperature response genes. Notably, HZ88 responds to low-temperature stress, its low-temperature response genes are primarily enriched in plant hormone signal transduction; cutin, suberine and wax biosynthesis; and photosynthesis-antenna proteins. Conversely, the most significant low-temperature response genes of the LS6 strain were determined to be enriched in plant-pathogen interactions, zeatin biosynthesis, and plant hormone signal transduction. The cuticle, composed of a horny waxy layer, is an important protective barrier formed by plants to resist biotic/abiotic stress during the long-term ecological adaptation process, and the HZ88 strain may strengthen its cold resistance by enhancing this physical defence measure. In the LS6 strain, potatoes tend to cope with cold stress by strengthening their immune system and regulating hormone signal transduction. In addition, hormone pathway-related genes (such as ABA), ICE-CBF signalling pathway-related genes, and genes encoding TFs all exhibited different expression patterns between HZ88 and LS6.\nConclusions\n\nTo the best of our knowledge, this study is the first to elucidate the genetic mechanisms underlying the difference in cold resistance between the strongly cold-tolerant variety LS6 and the weakly cold-tolerant variety HZ88, thereby establishing a foundation for further analysis and genetic breeding.