Soil available phosphorus (AP), available nitrogen (AN), and available potassium (AK) are key indicators of soil fertility. Elucidating the impacts of phosphorus-solubilizing bacteria (PSB) on soil nutrient availability is critical for improving soil fertility and promoting sustainable agriculture. Using a meta-analysis method, this study systematically evaluated the effects of different factors, including soil pH, soil organic matter (SOM), PSB types, and crop types, on the changes in soil nutrient availability induced by PSB inoculation. Compared to non-inoculated controls, PSB inoculation significantly increased soil AP, AN, and AK by 86.8%, 64.9%, and 40.9%, respectively. Subgroup meta-analyses revealed that soil pH, SOM, PSB types, and crop types significantly modulated PSB-induced enhancements in soil AP. SOM, PSB types, and crop types significantly regulated the PSB-induced enhancement of soil AN. Meanwhile, PSB types notably modulated the enhancement of soil AK. Further analysis revealed a significant negative correlation between soil pH and the efficacy of PSB in enhancing soil AP, whereas SOM was significantly positively correlated with the ability of PSB to enhance soil AP and AN. These findings highlight the need for targeted consideration of soil pH, SOM, PSB types, and crop types in PSB inoculation to improve soil nutrient availability. This study provides empirical evidence for the systematic and efficient utilization of PSB to improve soil nutrient availability.
Jia et al. (Fri,) studied this question.