Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences (CAAS), Beijing, 100081, China.
National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, 38000, Pakistan.
Mycorrhiza. 2024 Nov;34(5-6):477-488. doi: 10.1007/s00572-024-01165-5. Epub 2024 Aug 8.
Rhizospheric interactions among plant roots, arbuscular mycorrhizal fungi, and plant growth-promoting bacteria (PGPB) can enhance plant health by promoting nutrient acquisition and stimulating the plant immune system. This pot experiment, conducted in autoclaved soil, explored the synergistic impacts of the arbuscular mycorrhizal fungus Funneliformis mosseae with four individual bacterial strains, viz.: Cronobacter sp. Rz-7, Serratia sp. 5-D, Pseudomonas sp. ER-20 and Stenotrophomonas sp. RI-4 A on maize growth, root functional traits, root exudates, root colonization, and nutrient uptake. The comprehensive biochemical characterization of these bacterial strains includes assessments of mineral nutrient solubilization, plant hormone production, and drought tolerance. The results showed that all single and interactive treatments of the mycorrhizal fungus and bacterial strains improved maize growth, as compared with the control (no fungus or PGPB). Among single treatments, the application of the mycorrhizal fungus was more effective than the bacterial strains in stimulating maize growth. Within the bacterial treatments, Serratia sp. 5-D and Pseudomonas sp. ER-20 were more effective in enhancing maize growth than Cronobacter sp. Rz-7 and Stenotrophomonas sp. RI-4 A. All bacterial strains were compatible with Funneliformis mosseae to improve root colonization and maize growth. However, the interaction of mycorrhiza and Serratia sp. 5-D (M + 5-D) was the most prominent for maize growth improvement comparatively to all other treatments. We observed that bacterial strains directly enhanced maize growth while indirectly promoting biomass accumulation by facilitating increased mycorrhizal colonization, indicating that these bacteria acted as mycorrhizal helper bacteria.
根际中植物根系、丛枝菌根真菌和植物促生细菌（PGPB）之间的相互作用可以通过促进养分吸收和刺激植物免疫系统来增强植物健康。本盆栽实验在灭菌土壤中进行，探索了丛枝菌根真菌摩西管柄囊霉与四种单独细菌菌株（即： Cronobacter sp. Rz-7、 Serratia sp. 5-D、 Pseudomonas sp. ER-20 和 Stenotrophomonas sp. RI-4 A）对玉米生长、根系功能特性、根系分泌物、根定植和养分吸收的协同影响。这些细菌菌株的综合生化特性包括评估其对矿物养分的溶解能力、植物激素的产生能力和耐旱性。结果表明，与对照（无真菌或 PGPB）相比，菌根真菌和细菌菌株的所有单一和互作处理均能提高玉米生长。在单一处理中，与细菌菌株相比，菌根真菌更能刺激玉米生长。在细菌处理中， Serratia sp. 5-D 和 Pseudomonas sp. ER-20 比 Cronobacter sp. Rz-7 和 Stenotrophomonas sp. RI-4 A 更能有效促进玉米生长。所有细菌菌株均与摩西管柄囊霉相容，以提高根定植和玉米生长。然而，与所有其他处理相比，菌根和 Serratia sp. 5-D（M+5-D）的互作更能显著提高玉米生长。我们观察到细菌菌株直接促进了玉米的生长，同时通过促进根定植间接促进了生物量的积累，表明这些细菌充当了菌根促生菌。
