Liu Qi, Zhao Xiaowen, Liu Yue, Xie Sasa, Xing Yuanjun, Dao Jicao, Wei Beilei, Peng Yunchang, Duan Weixing, Wang Ziting
Guangxi Key Laboratory of Sugarcane Biology, Nanning, China.
College of Agronomy, Guangxi University, Nanning, China.
Front Microbiol. 2021 Oct 6;12:716196. doi: 10.3389/fmicb.2021.716196. eCollection 2021.
Sugarcane is an important sugar and energy crop, and its yield is greatly affected by drought. Although a large number of studies have shown that rhizosphere microorganisms can help improve the adaptability of plants to biotic or abiotic stresses, there is a lack of studies on the adaptability of sugarcane rhizosphere microbial communities to host plants. Therefore, we conducted drought stress treatment and normal irrigation treatment on three sugarcane varieties GT21, GT31, and GT42 widely cultivated in Guangxi. Using 16S rDNA sequencing technology to analyze the changes in abundance of the sugarcane rhizosphere bacterial community under different treatments, combined with the determination of soil enzyme activity, soil nutrient content, and sugarcane physiological characteristics, we explored the sugarcane rhizosphere bacterial community response to drought stress. In addition, we used the structural equation model to verify the response path of sugarcane rhizosphere bacteria. The results show that the bacterial community structure in the rhizosphere of sugarcane is stable under normal water conditions. The change in the bacterial community structure under drought stress has a 25.2% correlation with the drought adaptability of sugarcane, but the correlation with drought stress is as high as 42.17%. The changes in abundance of rhizosphere bacteria under drought stress are mainly concentrated in the phylum Rhizobiales and Streptomycetales. This change is directly related to the physiological state of the host plant under drought stress, soil available phosphorus, soil urease and soil acid protease. We investigated the response species of rhizosphere microorganisms and their response pathways under drought stress, providing a scientific basis for rhizosphere microorganisms to assist host plants to improve drought adaptability.
甘蔗是一种重要的糖料和能源作物，其产量受干旱影响很大。尽管大量研究表明根际微生物有助于提高植物对生物或非生物胁迫的适应性，但缺乏关于甘蔗根际微生物群落对寄主植物适应性的研究。因此，我们对广西广泛种植的3个甘蔗品种GT21、GT31和GT42进行了干旱胁迫处理和正常灌溉处理。利用16S rDNA测序技术分析不同处理下甘蔗根际细菌群落丰度的变化，结合土壤酶活性、土壤养分含量和甘蔗生理特性的测定，探讨甘蔗根际细菌群落对干旱胁迫的响应。此外，我们还利用结构方程模型验证了甘蔗根际细菌的响应路径。结果表明，正常水分条件下甘蔗根际细菌群落结构稳定。干旱胁迫下细菌群落结构的变化与甘蔗的干旱适应性有25.2%的相关性，但与干旱胁迫的相关性高达42.17%。干旱胁迫下根际细菌丰度的变化主要集中在根瘤菌目和链霉菌目。这种变化与干旱胁迫下寄主植物的生理状态、土壤有效磷、土壤脲酶和土壤酸性蛋白酶直接相关。我们研究了干旱胁迫下根际微生物的响应物种及其响应途径，为根际微生物协助寄主植物提高干旱适应性提供了科学依据。
