Table_3_Physiological and Gene Expression Changes of Clematis crassifolia and Clematis cadmia in Response to Heat Stress.XLSX

Clematis is a superior perennial ornamental vine known for varied colors and shapes of its flowers. Clematis crassifolia is sensitive to high temperature, whereas Clematis cadmia has a certain temperature adaptability. Here we analyzed the potential regulatory mechanisms of C. crassifolia and C. cadmia in response to heat stress by studying the photosynthesis, antioxidant parameters, amino acids, and gene expression patterns under three temperature treatments. Heat stress caused the fading of leaves; decreased net photosynthetic rate, stomatal conductance, superoxide dismutase, and catalase activity; increased 13 kinds of amino acids content; and up-regulated the expression of seven genes, including C194329_G3, C194434_G1, and C188817_g1, etc., in C. crassifolia plants. Under the treatments of heat stress, the leaf tips of C. cadmia were wilted, and the net photosynthetic rate and soluble protein content decreased, with the increase of 12 amino acids content and the expression of c194329_g3, c194434_g1, and c195983_g1. Our results showed that C. crassifolia and C. cadmia had different physiological and molecular response mechanisms to heat stress during the ecological adaptation.

铁线莲（Clematis）是一类优异的多年生观赏藤本植物，以其花型花色丰富多样而广受赞誉。其中厚萼铁线莲（Clematis crassifolia）对高温胁迫较为敏感，而毛柱铁线莲（Clematis cadmia）则具备一定的温度适应能力。本研究通过设置三种温度梯度处理，对厚萼铁线莲与毛柱铁线莲的光合特性、抗氧化参数、氨基酸含量及基因表达模式进行分析，以解析二者响应高温胁迫的潜在调控机制。在厚萼铁线莲植株中，高温胁迫可诱导叶片褪绿；降低净光合速率、气孔导度、超氧化物歧化酶与过氧化氢酶活性；提升13种氨基酸的含量；并上调包括C194329_G3、C194434_G1及C188817_g1等在内的7个基因的表达水平。在高温胁迫处理下，毛柱铁线莲的叶尖会出现萎蔫现象；其净光合速率与可溶性蛋白含量下降，同时12种氨基酸的含量上升，且c194329_g3、c194434_g1及c195983_g1的表达量显著上调。本研究结果表明，厚萼铁线莲与毛柱铁线莲在生态适应过程中，针对高温胁迫的生理与分子响应机制存在显著差异。