Effects of Thiobacillus, Sulfur and Micronutrient Spray on Some Traits of Green Beans

A factorial experiment with the split plot arrangement using the complete randomized block design with three replications was carried out adjacent to the Agriculture School of Shahrood University of Technology in 2010-2011 to study the effects of sulfur and Thiobacillus application and zinc and molybdenum sprays on some traits of green beans. The treatments included three levels of sulfur (zero, 100 kg/ha of sulfur powder, and 100 kg/ha of sulfur powder + Thiobacillus bacteria) as the main factor, and three levels of zinc spray (0, 5, and 10g/l) and two levels of molybdenum spray (0 and 0.5 g/l) as the sub-main factors. The treatments that included sulfur were applied before seeding. Zinc (using zinc sulfate) and molybdenum (using sodium molybdate) were sprayed during the growing season and 5 weeks after planting. Results showed the treatment of applying sulfur at 100 kg/hectare and Thiobacillus bacteria increased leaf fresh and dry weights by 57 and 54%, mean pod length by 14%, and number of lateral branches by 25% compared to the control. Moreover, this treatment increased pod fresh and dry weights by 41.6 and 42.11%, respectively, compared to the treatment of not applying sulfur, and improved yield by 42% compared to the control. Considering the results concerning yield in response to sulfur, zinc, and molybdenum, it can be said that application of sulfur and Thiobacillus together with zinc spray can be very useful in growing green beans.