Physiological Differences and Transcriptome Analysis Reveal That High Enzyme Activity Significantly Enhances Drought Tolerance in Chinese Fir (Cunninghamia lanceolata)

Chinese fir (Cunninghamia lanceolata) is the most cultivated timber species in China, with a plantation area of 11 million ha. Due to its extensive geographical distribution, drought stress caused by spatial and seasonal heterogeneity precipitation has limited survival productivity. To facilitate breeding drought-tolerant clones understand inter-response mechanisms stress, we screened two (DT) evaluated their differences physiological molecular response drought. The results showed that No. 228 clone (high-DT ability) had higher antioxidant enzyme abilities than 026 (low-DT under e.g., peroxidase (POD), polyphenol oxidase (PPO), superoxide dismutase (SOD), catalase (CAT). Transcriptome analyses revealed 6637 genes 1168 were up-regulated respectively, when compared control (CK). may participate drought-stimulated signal transduction, water/oxygen-containing compound synthesis, photosynthesis, transmembrane transport functions. Particularly, 14,213 differentially expressed (DEGs) observed clone, 4274 (15-fold difference). These significant DEGs involved plant hormone flavonoid biosynthesis, peroxisomes, other key pathways related Interestingly, Chitinases (ClCHIs) four POD (ClPERs) induced express 228, which was consistent activities 228. A heat map 49 dehydrin family genes, ion binding/transmembrane proteins, auxin receptor ethylene-responsive transcription factors significantly stress. can enhance our understanding tolerance provide guideline for screening DT clones.