Sulfur-oxidizing buffalo dung bacteria enhance growth and yield of Foeniculum vulgare Mill.

This study aimed to harness the benefits of sulfur-oxidizing beneficial bacteria from buffalo dung to improve crop yields of Foeniculum vulgare. A total of 61 bacterial isolates were screened from buffalo dung, of which 40 isolates exhibited plant-growth-promoting attributes, such as phosphate solubilization, indole-3-acetic acid production, and hydrogen cyanide production. Of these 40, four bacterial isolates, viz., BUFF12, BUFF14, BUFF23, and BUFF38, were the most potent, having plant-growth-promoting and sulfur-oxidizing properties. These four isolates produced phytase by solubilizing calcium phytate and sodium phytate. They solubilized potassium besides oxidizing the sulfur, causing an increase in soil fertility and crop production. All four isolates were nonpathogenic in nature, as demonstrated by a negative haemolysis test. According to the 16S rRNA gene sequence, the isolate BUFF14 was identified as Proteus mirabilis. Proteus mirabilis BUFF14 maximized seed germination with enhanced vegetative and reproductive parameters during pot and field trial studies, compared with the other isolates.