Diagnosis of sulfur deficiency and effects of sulfur on yield and yield components of wheat grown in Central Anatolia, Turkey

Deficiency of sulfur (S) has been recognized as a limiting factor for crop production in many regions of the world. A survey study was initiated to determine the current S nutritional status of wheat plants in Ankara, Turkey in the cropping season of 1999-2000. Owing to the results of the survey study signing soil and plant S deficiency, a greenhouse and field study were conducted during 2000-2001 on the effect of S on yield and yield components of bread (Triticum aestivum L. cv. Bezostaja) and durum (Triticum durum L. cv. Kiziltan) wheat cultivars. According to the survey study results, more than 50% of the soil, plant straw, and grain samples contained lower S than the critical limits. Significant positive correlations were observed between total and extractable soil-S (r = 0.4799), and also between both the total and extractable soil-S and grain-S (r = 0.3097 and r=0.4162). Additionally significant positive correlation was observed between straw and grain-S (r = 0.4500). Yield and some of the yield components in both wheat cultivars were significantly responded to the application of S fertilizer in the greenhouse and field experiments, which conducted with a soil containing 12.78mg extractable Skg(-1) soil. Dry weights of Bezostaja and Kiziltan increased from 4.38 to 4.72 g pot(-1) and 3.03 to 3.26 g pot(-1) respectively, at the minimal dose of S (10 mg S kg(-1)) application in the greenhouse study. In the field study, grain yield increased from 3472 to 4869 kg ha(-1) in Bezostaja and 4787 to 5804 kg ha(-1) in Kiziltan at the minimal dose of applied S (20 kg S ha(-1)). After these levels of S application, the differences among the S levels with respect to yield were found not to be significant both in the greenhouse and field study. Concentration of S in plant, grain yield per spike and harvest index for 2 both cultivars, and spike number m(-2), spike length, fertile and sterile spikelet number per spike for Bezostaja, and thousand kernel weight for Kiziltan were responded positively to S fertilization in field conditions. On the other hand, the ratio of N/S in the grain and shoots of both cultivars decreased by S fertilization.