Growth and productivity of wheat affected by phosphorus-solubilizing fungi and phosphorus levels

Phosphorus (P) availability limits crop growth in most of cultivable soils in north-west India. The beneficial rhizo-sphere microorganisms such as phosphate-solubilising fungi (PSF) were found to increase P availability in soil and improve crop yields. In view of this, field experiments were conducted during 2009-2011 to evaluate the effect of seed inoculation with PSF (Penicillium bilaii) at different rates of fertilizer P on P content in leaves and grain yield of irrigated wheat in India. The soil was low in Olsen P at the Bathinda site and medium at the Ludhiana site. In no-P treatment, PSF significantly increased grain yield by 12.6% over non-inoculated control. The effect of PSF on grain yield was generally more pronounced in a soil with low Olsen-P compared to medium Olsen-P level. Inoculation of PSF along with 50% P fertilizer increased wheat yield equivalent to 100% P with no PSF. Spike density was significantly higher in PSF + 50% P than all the other treatments. There is need to study a long-term effect of Penicillium bilaii on P-fertilizer saving in wheat on soils varying in P availability, pH and P fixation capacity for different wheat-based cropping systems.