PDF
Full
Outline
[Objective] The rhizosphere microorganism-plant combined approach has high application potential for the remediation of heavy metal-contaminated soil. This study observed the effects of adding exogenous plant growth-promoting bacteria (PGPB) on the growth and molybdenum (Mo) accumulation of alfalfa (Medicago sativa), aiming to provide theoretical references for plant-microbial remediation of Mo-contaminated soil. [Methods] The endophytic bacteria were isolated from dominant plants of Mo tailing and they were identified based on morphological characteristics and molecular evidence. The plant growth-promoting (PGP) properties of molybdate-reducing strains were determined. By adding exogenous PGPB into the soil, we investigated the effects of adding exogenous PGPB on the biomass, physiological activity, and Mo accumulation of alfalfa. [Results] Two molybdate-reducing strains M9 and M13 were obtained and identified as Serratia plymuthica based on morphological characteristics, 16S rRNA gene sequence, and gyrB sequence. M9 and M13 had the abilities to fix nitrogen, solubilize phosphorus, solubilize potassium, and secrete indole-3-acetic acid (IAA), siderophores, and 1-amino cyclopropane-1-carboxylic acid (ACC) deaminase. Under Mo stress, the inoculation of M9, M13, and M9+M13 significantly promoted the growth of alfalfa, increasing the plant height, root length, and fresh weight of alfalfa compared with the non-inoculation control group. At the same time, the inoculation increased the chlorophyll content and peroxidase (POD) activity while decreasing the malondialdehyde (MDA) content in alfalfa. M9 and M13 significantly affected the Mo accumulation of alfalfa. The Mo content in the above-ground and under-ground parts of alfalfa inoculated with M9, M13, and M9+M13 significantly decreased compared with that in the non-inoculation control group. The decreased enrichment factor of Mo in alfalfa indicated that inoculation with molybdate-reducing strains reduced the uptake and transport of Mo in alfalfa. [Conclusion] The molybdate-reducing strains M9 and M13 can promote the growth and reduce the Mo content of alfalfa in Mo-contaminated soil. This finding can provide theoretical reference for revealing the mechanism of microbial-enhanced Mo remediation by plants as well as the joint remediation of Mo-contaminated soil by plants and microorganisms.
PDF
126
50
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |
关闭全屏
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
