evaluation of integrated impact of sulfur and thiobacillus on qualitative and morphological characteristics of safflower (carthamustinctoriusl.)

considering high alkalinity of iranian soils and lack of availability of some nutrients in those conditions, sulfur consumption is one approach to increase the availability of insoluble nutrients especially in calcareous and alkaline soils. effectiveness of sulfur depends on activity of sulfur oxidizing bacteria especially thiobacillus genus (t). in order to study the qualitative yield and morphological characteristics of safflower (carthamustinctorius l.), a field experiment was carried out as factorial layout based on a randomized complete block design with three replications at the agricultural research station, college of agriculture, birjand university during growing season 2010-2011. treatments were including four sulfur levels (0, 300, 400 and 500 kg.ha-1) and four levels of thiobacillus (0, 1, 2 and 3 kg.ha-1 per 100 kg.ha-1 organic sulfur). studied traits were height and diameter of stems and qualitative characteristics of safflower such as protein and oil contents in seed and sulfur and phosphorus concentrations in leaf. results showed that the effect of sulfur and biosulfur with thiobacillusas a biofertilizer and their interaction effects were significant (p≤0.01) on oil and protein contents of seed, phosphorus and sulfur concentrations of leaf, and also on height and stem diameter of safflower. the highest seed protein content was observed in 500 kg.ha-1sulfur with 20.4% and the lowest was for control plots with 17.1%. the minimum oil content was recorded in control plots (18.7%) and the highest improvement compared to control was obtained in 500 kg.ha-1sulfur with 26%. the highest height and stem diameter of safflower were observed in 400 and 500 kg.ha-1sulfur with 3 kg.ha-1thiobacillus. so, it seems that integrated application of sulfur with thiobacillus inoculation is an ecological strategy for improving of qualitative and quantitative growth and producing of oil crops such as safflower.