Evaluation of the impact of potassium solubilizing bacteria on potassium efficiency and yield of canola under saline and non-saline soil conditions

Canola (Brassica napus L.) is one of the most important oilseed crops used globally for nutritional and industrial purposes. In the pursuit of sustainable agriculture goals, understanding plant-microbe interactions is necessary. This study aimed to evaluate the effects of seven levels of potassium sulfate fertilizer (K2SO4; 0, 25, 50, 75, 100, 125 and 150 kg ha−1), which at each of the following five potassium solubilizing bacteria (KSB; non-inoculated, Pantoea agglomerans, Rahnella aquatilis, co-inoculation (P. agglomerans+R. aquatilis) and a commercial biofertilizer ‘PotaBarvar-2’), on potassium uptake and yield of canola under saline and non-saline soil conditions. The results indicated that among KSB treatments, the highest values for all traits were observed when P. agglomerans and R. aquatilis together were applied, which could be considered as the best KSB treatment in both soil conditions. However, grain yield was increased by 39.7% (1226.4 kg ha−1) and 51.1% (1325.0 kg ha−1); the application of K2SO4 was reduced by 13.3% (10.9 kg ha−1) and 12.4% (13.9 kg ha−1) when the co-inoculation compared to the non-inoculated treatment under non-saline and saline soil conditions, respectively. Consequently, the application of P. agglomerans and R. aquatilis together can be recommended in sustainable canola production systems, particularly under saline soil conditions.