use of biofertilizers and conditioners in citrus nurseries in relation to microflora contributing to soil fertility

ABSTRACT

The effect of polyacrylamide gel soil conditioner, phosphate biofertilizer and rock-phosphate application on the microflora of a virgin sandy soil, was studied under sour orange at nursery stage in a pot experiment. There was a noticeable increase in the total bacterial counts in all treatments. Combinations of the three amendments exhibited the highest total bacterial, fungal and phosphate dissolving bacterial counts and extended the stationary phase. The treatments increased the asymbiotic nitrogen fixers, especially the aerobic Azotobacter, more than the anaerobic N fixing clostridia. The counts of nitrifying bacteria also increased more than the control