文献类型：期刊文献

英文题名：Physiological and biochemical mechanisms of drought regulating the size and color of heartwood in Dalbergia odorifera

作者：Cui, Zhiyi[1] Hu, Houzhen[1] Li, Xiaofei[1] Liu, Xiaojin[1] Zhang, Qilei[1] Hong, Zhou[1] Zhang, Ningnan[1] Lin, Wei[2] Xu, Daping[1]

第一作者：崔之益

通信作者：Xu, DP[1];Lin, W[2]

机构：[1]Chinese Acad Forestry, Res Inst Trop Forestry, Guangzhou 510520, Guangdong, Peoples R China;[2]Foshan Bot Garden, Foshan Inst Forestry, Foshan 528012, Guangdong, Peoples R China

年份：2025

卷号：45

期号：1

外文期刊名：TREE PHYSIOLOGY

收录：;Scopus(收录号：2-s2.0-85216500322);WOS:【SCI-EXPANDED(收录号:WOS:001397141100001)】；

基金：This research was supported by the Fundamental Research Funds for the Central Non-profit Research Institution of Chinese Academy of Forestry (CAFYBB2023MB007), the National Natural Science Foundation of China (32001307) and the National Key R&D Program of China (2022YFD2202000).

语种：英文

外文关键词：carbon isotope labeling; flavonoid; nonstructural carbohydrates; phloem; transition zone

摘要：Drought has been found to affect the size and color of precious heartwood of Dalbergia odorifera, but the mechanism remains unclear. For this purpose, we performed the measurement of heartwood size, color and flavonoid content and composition in a 15-year-old mixed plantation of D. odorifera and Santalum album that had been subjected to two levels of rainfall exclusion and control treatments for 7 years, and carbon isotope labeling and anatomical observation in 2-year-old potted D. odorifera seedlings exposed to two levels of drought and control treatments. The field experiment showed that drought had significant effects on heartwood size and color of D. odorifera. More starch was depleted in the transition zone (TZ) in drought than in control. Drought significantly decreased the values of color parameters and increased the contents of total flavonoids, glycitein, fisetin, chrysin and claussequinone, and total flavonoids, glycitein, fisetin, chrysin and claussequinone were significantly negatively correlated with L* and b*. The pot experiment showed that during longitudinal transport of nonstructural carbohydrate (NSC), the dilution factor of 13C abundance in the inner bark sap in severe drought (SD) was twice as much as that in control. The inner bark thickness and transverse area of sieve tubes in SD were significantly lower than those in control. Our findings further confirm that drought promotes the heartwood formation of D. odorifera, and discuss interspecific variations in the response of heartwood formation to drought. Drought enhances the exchange transport of NSC between phloem and xylem by reducing the transverse area of sieve tubes, thus causing more NSC to be transported into xylem, and drought also promotes the depletion of starch in the TZ to produce more heartwood. Drought darkens the heartwood color by increasing the contents of total flavonoids, glycitein, fisetin, chrysin and claussequinone in heartwood. To our knowledge, this is the first study addressing the physiological and biochemical mechanism of drought regulating heartwood formation.