Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China.
College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
Int J Mol Sci. 2022 Aug 26;23(17):9665. doi: 10.3390/ijms23179665.
The rhizospheric melatonin application-induced drought tolerance has been illuminated in various plant species, while the roles of the rhizosphere microbial community in this process are still unclear. Here, the diversity and functions of the rhizosphere microbial community and related physiological parameters were tested in barley under the rhizospheric melatonin application and drought. Exogenous melatonin improved plant performance under drought via increasing the activities of non-structural carbohydrate metabolism enzymes and activating the antioxidant enzyme systems in barley roots under drought. The 16S/ITS rRNA gene sequencing revealed that drought and melatonin altered the compositions of the microbiome. Exogenous melatonin increased the relative abundance of the bacterial community in carbohydrate and carboxylate degradation, while decreasing the relative abundance in the pathways of fatty acid and lipid degradation and inorganic nutrient metabolism under drought. These results suggest that the effects of melatonin on rhizosphere microbes and nutrient condition need to be considered in its application for crop drought-resistant cultivation.
根际褪黑素应用诱导的耐旱性已在各种植物物种中得到阐明，而根际微生物群落在此过程中的作用尚不清楚。在这里，在根际褪黑素应用和干旱条件下，对大麦中的根际微生物群落的多样性和功能以及相关生理参数进行了测试。外源褪黑素通过增加非结构性碳水化合物代谢酶的活性和激活大麦根中的抗氧化酶系统，在干旱条件下提高了植物的性能。16S/ITS rRNA 基因测序显示，干旱和褪黑素改变了微生物组的组成。外源褪黑素增加了碳水化合物和羧酸降解细菌群落的相对丰度，而在干旱条件下降低了脂肪酸和脂质降解以及无机养分代谢途径的相对丰度。这些结果表明，在应用褪黑素进行作物抗旱栽培时，需要考虑其对根际微生物和养分状况的影响。
