Field plus lab experiments help identify freezing tolerance and associated genes in subtropical evergreen broadleaf trees: A case study of Camellia oleifera

作者：Haoxing Xie, Jian Zhang, Junyong Cheng, Songzi Zhao, Qiang Wen, Ping Kong, Yao Zhao, Xiaoguo Xiang, Jun Rong · 发表于：Frontiers in Plant Science · 年份：2023 · DOI：10.3389/fpls.2023.1113125 · 被引用次数：11 · 研究领域：Plant Stress Responses and Tolerance、Plant Gene Expression Analysis、Plant Molecular Biology Research

The molecular mechanisms of freezing tolerance are unresolved in the perennial trees that can survive under much lower freezing temperatures than annual herbs. Since natural conditions involve many factors and temperature usually cannot be controlled, field experiments alone cannot directly identify the effects of freezing stress. Lab experiments are insufficient for trees to complete cold acclimation and cannot reflect natural freezing-stress responses. In this study, a new method was proposed using field plus lab experiments to identify freezing tolerance and associated genes in subtropical evergreen broadleaf trees using Camellia oleifera as a case. Cultivated C. oleifera is the dominant woody oil crop in China. Wild C. oleifera at the high-elevation site in Lu Mountain could survive below −30°C, providing a valuable genetic resource for the breeding of freezing tolerance. In the field experiment, air temperature was monitored from autumn to winter on wild C. oleifera at the high-elevation site in Lu Mountain. Leave samples were taken from wild C. oleifera before cold acclimation, during cold acclimation and under freezing temperature. Leaf transcriptome analyses indicated that the gene functions and expression patterns were very different during cold acclimation and under freezing temperature. In the lab experiments, leaves samples from wild C. oleifera after cold acclimation were placed under −10°C in climate chambers. A cultivated C. oleifera variety “Ganwu 1” was used ...