Physiological resistance of Dendrocalamus brandisii culms to alcohol stress during living bamboo wine production process.

Abstract

Background: Currently, living bamboo wine has gained immense popularity in China. However, the effects of alcohol on the physiological processes of bamboo during the production of living bamboo wine have not yet been investigated.

Methods: To investigate the resistance of bamboo culms to the alcohol-induced stress, we conducted a comprehensive analysis of various factors, including changes in cell wall chemical components, antioxidant defense systems, endogenous plant hormones and transcriptomics, both before and after the alcohol injection.

Results: The results showed that alcohol injection caused more (8.33 ± 8.33%) significant damage to the 1-year-old culms (22.22 ± 4.81%) than that to those aged 2 and 3 years. Bamboos aged 2 years exhibited a superior capacity to rapidly activate their physiological defenses against alcohol stress. The upregulation of key genes in the jasmonic acid biosynthesis pathway, including LOX2S, AOS, MFP2, and OPR, along with an increased accumulation of jasmonic acid, were pivotal in conferring alcohol resistance to bamboo culms post-injection. Additionally, alcohol induced the upregulation of critical genes involved in the lignin and cellulose deposition pathways, such as PAL, 4CL, CAD, SUS and UGP, which lead to enhanced lignin and cellulose deposition, thereby reinforcing the bamboo's resistance to alcohol stress. The SOD enzyme and the AsA-GSH cycle played a crucial role in the bamboo's defense against alcohol-induced stress.

Conclusions: The 2-year-old bamboo culms emerged as the optimal choice for living bamboo wine production, due to their exceptional tolerance to alcohol stress. This could provide theoretical guidance for the commercial production of the living bamboo wine and the administration of bamboo forests.