Growth, nodulation and yield components of mung bean (Vigna radiata) as affected by phosphorus in combination with rhizobium inoculation

Mungbean (Vigna radiata L.) is capable of fixing atmospheric nitrogen through bacteria living in its root nodules. To study the influence of phosphorus (P) fertilization and Rhizobium inoculation on the nodulation, growth and yield of mungbean (Vigna radiata), a pot experiment was conducted in wire house, during spring season of 2010 at University of Agriculture, Faisalabad. A composite soil sample was collected from the research area and analysis of physical and chemical properties of the soil was done. Seeds of mungbean cv, NM-92 were inoculated with Rhizobium and sown in pots containing 14 kg soil. Phosphorus was applied at 1.2, 2.4 and 3.6 g per 14 kg soil in each pot alone and along with inoculation of Rhizobium phaseoli except in control pot. The source of P was single super phosphate that was mixed with soil before filling the pots. It was noted that combined use of P and inoculant enhanced the number of nodules per plant. The maximum nodules, 8.67 per plant, were recorded where 3.6 g P along with Rhizobium inoculation was applied. Phosphorus application along with Rhizobium inoculation increased the plant height significantly (13.2%) over control. Maximum increase in plant height at maturity, total number of pods and number of grains per pod were also recorded where 3.6 g of phosphorus along with Rhizobium inoculation was applied. Key words: Mungbean, growth, nodulation, phosphorus, inoculation.