Response of corn to foliar application of plant growth promoting rhizobacteria and co-inoculation of seed with biofertilizers

In order to study the effect of foliar application and co-inoculation of seed with PGPR bacteria on quantitative and qualitative characteristics of corn, an experiment was conducted at research field of Islamic Azad University, Varamin Branch in Iran during 2011 growing season. A factorial experiment in the form of complete randomized block design with four replications was used. The factors in this study included inoculation seed with biofertilizer (with and without PGPR inoculation bacteria) and foliar application of biofertilizer in six levels (non-foliar application, foliar application with PGPR bacteria at 8-leaf stage plants, stem elongation stage plants, tassel stage plants, pistillate inflorescence stage plants and milk development). The results showed that the interaction effect between inoculation x foliar application with PGPR had significant effect on all traits under examination except 1000-seed weight and seed yield. This study indicated that the highest height plant, dry weight per plant, row number in ear, seed number in row, total seed number in ear and seed yield were obtained in conditional inoculation seed and foliar application with PGPR at 8-leaf stage. Also, this result showed that foliar application with PGPR bacteria at 8-leaf stage plants increased seed yield by 17.39%, respectively, as compared with non-foliar application in inoculation with biofertilizer condition. Our results suggested that foliar application and inoculation of PGPR bacteria not only decreased chemical fertilizers but also increased grain yield, also this prevented from ecosystem pollution.