Interaction of sulfur and thiobacillus bacteria on colonization of two species of mycorrhiza fungi and maize growth under greenhouse conditions

A factorial experiment based on complete block design was conducted to study the interactive effects of sulfur fertilizer and thiobacillus bacteria on corn growth and root colonization with two species of mycorrhiza fungi. Treatments were five levels of sulfur (S0: 0, S1: 50, S2: 100, S3: 150 and S4: 200 mg.kg-1 of dry soil), thiobacillus in two levels [no application (T0) and application of bacteria (T1)] and mycorrhiza inoculation in three levels [control (M0), Glomus intraradices (M1) and Glomus mosseae (M2)]. Results showed that sulfur and thiobacillus application increased leaf chlorophyll, shoot dry weight, root dry weight, shoot and root heights. Inoculation of seed with Glomus intraradices and Glomus mosseae significantly increased root dry weight (15.9 and 14.5 percent, respectively), root colonization (88.8 percent) and root height (6 and 1.1 percent, respectively) compared to control. Single or combined sulfur and thiobacillus application had a negative effect on root colonization percentage. High sulfur application reduced colonization of Glomus mosseae more than Glomus intraradices. The interaction of sulfur and thiobacillus appeared to be significant on all studied traits except chlorophyll content.