PAN Xiao-xue
Biotechnology Research Center, Chongqing Academy of Agricultural Sciences/Chongqing Key Laboratory of Adversity AgricultureZHANG Xian-wei
Chongqing Ratooning Rice Research Center, Chongqing Academy of Agricultural SciencesLI Jing-yong
Chongqing Ratooning Rice Research Center, Chongqing Academy of Agricultural SciencesLEI Kai-rong
Biotechnology Research Center, Chongqing Academy of Agricultural Sciences/Chongqing Key Laboratory of Adversity Agriculture1Biotechnology Research Center, Chongqing Academy of Agricultural Sciences/Chongqing Key Laboratory of Adversity Agriculture, Chongqing 401329; 2Chongqing Ratooning Rice Research Center, Chongqing Academy of Agricultural Sciences, Chongqing 402160
Program for Young Innovative Research Team in Chongqing Academy of Agricultural Sciences(NKY-2018QC04)
“Late spring coldness” negatively affects rice seedling establishment and leads to rice growth retardation, albinism and rotten in Chongqing and southwest China, which severely restricts the production of high-quality rice and the application of optimal cultivation technologies. To investigate the cold tolerance of the chilling-tolerant indica cultivar Yu17S and chilling-sensitive indica cultivar Y58S seedlings, different parameters including the contents of soluble sugar, trehalose, proline, MDA and H2O2, the activities of antioxidant enzyme( SOD, POD and CAT), and the relative expression of stress relative genes were deployed. If compared with Y58S with the dead seedlings rate of up to 96.7%, Yu17S represented 7.5% of the dead seedlings rate, suggesting a stronger cold tolerance at the seedling stage upon the low temperature stress. The contents of both H2O2 and MDA increased in both cultivars under the low temperature stress, whereas both values of Yu17S were lower than these of Y58S. In Yu17S, the CAT, SOD and APX activity, soluble sugar and trehalose content, as well as the transcripts of genes OsCATB, OsSOD, OsAPx8, OsTPS1, OsTPP1, OsMKK6, OsMAPK3 and OsICE1 have been observed to be significantly increased. No significant differences on the proline content and on the expression of OsP5CS that controls the proline biosynthesis in both cultivars were observed. It is possible that the H2O2 signal molecule and trehalose of Yu17S may respond to the low temperature stress at the seedling stage, thus resulting in an enhancement on cold resistance.