Effects of AM fungi and phosphate-solubilizing bacteria inoculation on maize growth and soil fertility under water stress

To resolve the issue of water and soil nutrient deficiency in the eastern Inner Mongolia coal mining area,a pot experiment was carried out to investigate the effects of single inoculation with arbuscular mycorrhizal(AM) fungi(Funneliformis mosseae),single inoculation with phosphate-solubilizing bacteria(Pantoea stewartii) and dual-inoculation with AM fungi and phosphate-solubilizing bacteria on maize biomass and N,P,K uptake,and rhizosphere soil chemical properties under normal water condition(70% of the soil water holding capacity) and water stress(70% of the soil water holding capacity).The results showed that the treatment of AM fungi or phosphate-solubilizing bacteria inoculation had some promotion effects on maize biomass and its N,P,K uptake,and soil chemical fertility under normal water condition and water stress.Under normal water condition,dual-inoculation with AM fungi and phosphate-solubilizing bacteria was the best way to increase maize dry matter.Compared with the control(CK),dual-inoculation with AM fungi and phosphate-solubilizing bacteria increased plant above-ground biomass,root biomass and total biomass by 55.5%,25.6% and 49.0%,and promoted plant N,P and K uptake by 71%,83% and 50%,respectively.Dual-inoculation with AM fungi and phosphate-solubilizing bacteria increased the soil available P content and phosphatase activity by 92.3% and 5.3%,respectively,while single inoculation with AM fungi was the best way to improve soil pH and conductivity,and increase soil organic matter,total nitrogen and available K content.Under water stress,single inoculation with AM fungi increased the maize dry matter,improved soil pH and conductivity,and increased soil total nitrogen and available P content compared with the other three treatments,which significantly increased maize biomass by 51% and plant N,P and K uptake by 60%,111% and 86%,respectively.Therefore,the synergy between AM fungi and phos-phate-solubilizing bacteria can promote plant growth and soil fertility,thus accelerating the process of vegetation restoration and ecological reconstruction,and it provides a scientific reference for the application of microbial reclamation in the mining area.