Identification of Key Regulatory Factors of Molecular Marker TGS377 on Chromosome 1 and Its Response to Cold Stress in Tomato

Abstract

Low temperature, as a kind of stress factor, often leads to tomato growth stagnation or yield reduction or even no harvest in production. At present, numerous genes have been shown to be involved in the regulation of cold resistance in the tomato. Complex regulatory mechanisms responding to low temperature stress in the tomato are still unclear in their details. In this study, six accessions of tomato (‘NL-7’, ‘NL-15’, ‘NL-18’, ‘NL-21, ‘NL-37’, and ‘NL-67’) with different cold tolerance were selected to detect the response to low temperature. The results showed that ‘NL-15’, ‘NL-18’, and ‘NL-21’ tomato accessions had cold tolerance under 8 °C/6 °C (day/night) for 15-day treatments. The TGS377 molecular marker, closely related to cold tolerance, was located on chromosome 1. The potential factors were identified and bioinformatics analysis within 50 kb upstream and downstream of TGS377. Fifteen genes were identified, and their structural analysis and functional annotation were also performed. The expression levels of Solyc01g008480 and Solyc01g150104 in the cold-sensitive tomato accessions (‘NL-7’, ‘NL-37’, and ‘NL-67’) were higher than that in the cold-tolerant accessions (‘NL-15’, ‘NL-18’ and ‘NL-21’). The expression levels of Solyc01g008390 and Solyc01g008410 in the cold-tolerant tomato ‘NL-18’ accession was significantly higher than that in the cold-sensitive accessions (‘NL-15’, ‘NL-18’, and ‘NL-21’). The results suggested that these genes may be involved in regulating low temperature response in the tomato, which lays a foundation for the search of potential cold response regulators in the tomato.