effect of applying of sulfur along with thiobacillus inoculant and manure on leaf nutrient contents and vegetative growth characteristics in date palm ‘barhee’

abstract date palm, phoenix dactylifera, is one of the most important horticultural crops in iran. the most soils in iran, especially those cultivated with palm, are calcareous with high ph. the high ph of soil causes reduction of nutrient elements absorption. findings of researches show that application of elemental sulfur along with tiobacillus bacteria in soil, due to sulfur oxidation, reduce local ph in rizosphere area and consequently increase nutrient element availability for plant. in order to study the effect of application of sulfur along with thiobacillus inoculants and manure on leaf nutrient contents of leaf and vegetative growth characteristics in date palm ‘barhee’ an experiment was carried out using randomized completed block design with four treatments and four replications (each replication consisted of two date palm seedlings) during three years in ahvaze (khuzestan province). the treatments were: t1= control, which consisted of application of 40 kg manure based on general recommendation for each tree, t2 = t1 + application elemental sulfur as 10 % of manure + thiobacillus inoculants, t3 = t1 + application elemental sulfur as 20 % of manure + thiobacillus inoculants and t4 = t1 + application elemental sulfur as 30 % of manure + thiobacillus inoculants. the results showed that application of elemental sulfur along with thiobacillus inoculants and manure was improved plant ability to uptake mineral nutrients such as p, k, zn and mn as comparison with the control treatment of soil. improving plant mineral nutrients caused increasing vegetative growth characteristics such as number and length of leaf, number and length of leaflet, height of date palm seedlings. treatment 2, including: application of 40 kg manure, 4 kg elemental sulfur and thiobacillus inoculants in soil at planting time, due to least application of sulfur as comparison with the other treatments of sulfur application and the highest leaf nutrient contents and vegetative growth characteristics of date palm seedlings was the best treatment and for application is recommended.