Affiliation:
1. State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of State Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
Abstract
The increase in the atmospheric carbon dioxide concentration promotes its accumulation in trees by regulating the synthesis and transportation genes for endogenous hormones, such as IAA and GA, which are key factors in regulating various life activities, including growth rings. To explore the impact of changes in endogenous hormone levels such as IAA and GA on the growth of tree rings, and to provide a basis for improving the management of hybrid larch clonal forests, we investigated the effects of exogenous indole-3-acetic acid (IAA), gibberellic acid 3 (GA3), and their combination on tree-ring growth in hybrid larch. IAA, GA3, and a combination treatment were sprayed on the leaves of one clone of a hybrid larch seedling every three days. Small blocks were collected at the base stems for sequential anatomical observations. The phytohormone type, instead of the concentration, had a more significant effect on wood formation. Specifically, IAA treatment at 300 mg L−1 significantly increased latewood (LW) layers until 90 days after treatment (DAT). The 500 mg L−1 treatment significantly increased the wall radial thickness (WRT) of latewood (LW) cells. GA3 treatment at 100 mg L−1 significantly decreased the layers and width of total wood (TW), LW, and earlywood (EW). The 300 mg L−1 treatment significantly increased the WRT of EW. The IAA 100 mg L−1 + GA3 100 mg L−1 combination treatment significantly increased the layers and width of TW and LW by inducing cambium activity and increasing the rate of wood cell development. The WRT and lumen radial diameter (LRD) of EW or LW in this treatment were similar to those observed with the corresponding single phytohormone treatment. These results indicate that combination treatment at 100 mg L−1 + 100 mg L−1 was a better way to promote tree-ring growth. Our study suggests that changes in phytohormone levels and ratios are important factors that affect tree-ring formation. Hormone levels and ratios should be regarded as important indicators to guide the improvement of management practices in hybrid larch clonal plantations.
Funder
The National Key Research and Development Program of China
General Program of National Natural Science Foundation of China
The Special Funds of Research Institute of Forestry
Subject
Management, Monitoring, Policy and Law,Renewable Energy, Sustainability and the Environment,Geography, Planning and Development,Building and Construction
Reference46 articles.
1. Abscisic acid-independent Stomatal CO2 Signal Transduction Pathway and Convergence of CO2 and ABA Signaling Downstream of OST1 Kinase;Yohei;Proc. Natl. Acad. Sci. USA,2018
2. Elevated CO2-Induced Responses in Stomata Require ABA and ABA Signaling;Chater;Curr. Biol.,2015
3. Global Transcriptomic Profiling of Aspen Trees under Elevated CO2 to Identify Potential Molecular Mechanisms Responsible for Enhanced Radial Growth;Wei;J. Plant Res.,2013
4. A Novel CO2-responsive Systemic Signaling Pathway Controlling Plant Mycorrhizal Symbiosis;Yanhong;New Phytol.,2019
5. Wu, F., Sun, X., Zou, B., Zhu, P., and Ji, K. (2019). Transcriptional Analysis of Masson Pine (Pinus massoniana) under High CO2 Stress. Genes, 10.
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