Application of potassium-solubilising Proteus mirabilis MG738216 inhabiting cattle dung in improving nutrient use efficiency of Foeniculum vulgare Mill

The present research is aimed to evaluate buffalo dung inhabiting potassium solubilising bacteria (KSB) comprising characteristics of plant growth promotion to improve growth and yield of Foeniculum vulgare Mill. As buffalo dung has been used from ancient time in agricultural practices, it was selected as a source to harness the KSB that may enhance vegetative and reproductive parameters of F. vulgare. In total 15 KSB isolates were selected for solubilizing insoluble potassium in the form of mica powder. Four isolates BUFF12, BUFF14, BUFF23 and BUFF38 having abilities of plant growth promotion such as IAA production, HCN production, P solubilisation and phytase production performed better (after seed bacterization) in terms of plant growth. On the basis of 16S rRNA gene sequencing, the most potential KSB isolate was identified as Proteus mirabilis. Selected isolate P. mirabilis increases vegetative and reproductive parameters of F. vulgare. It increased grain yield by 55.03%, biological yield by 39.06% and harvest index by 11.49% over control. It exhibited the most pronounced advantageous effect on the growth and nutrient uptake by F. vulgare. P. mirabilis proved as a bio-inoculant and can be used as substitute of K fertilizer for raising crop of F. vulgare in sustainable manner.