Evaluation of Effects of Thiobacillus, Sulfur and Phosphorous on Corn (Zea mays L.) Growth Indices in some Regions of Iran

The availability of some nutrient elements in many soils of Iran is low because of high pH values. Therefore, any strategy for solution of this problem is important. This study carried out to evaluate the possibility of sulfur-bentonite application and Thiobacillus neapolitanous inoculation on corn (Single Cross 704) growth as factorial field experiments in Mashhad, Kermanshah, Qazvin and Dezful regions. The treatments were sulfur (control, 500, 1000 and 2000 kg ha-1) and triple super phosphate (control, 65 and 100% of recommended based on soil testing). The results revealed that sulphur, phosphorous and their interaction increased significantly corn shoot dry and wet weight. The sulfur application compared to control, significantly increased corn wet and dry matter. There was no significant difference between 1000 and 2000 kg S ha-1, but these levels showed significant difference with 500 kg S ha-1. All of the sulfur levels increased significantly the Fe uptake compared to the control, however, no difference observed between 500 and 1000 kg S ha-1, while application of 2000 kg sulfur resulted to the highest Fe uptake. The best treatment increased corn yield by 61, 9.8, 16.8 and 17.9 % in Mashhad, Qazvin, Kermanshah and Dezful respectively. Iron uptake increment at mentioned regions were 2%, 43%, 16.6% and 22.6%, respectively.