اثر منابع نيتروژن و مواد تسريع كننده تجزيه زيستي بر لايه كاهبرگ در سبز فرش ورزشي

A randomized complete block experiment with seven treatments and three replications was carried out in order to application of biological decomposing accelerators and comparison between effectiveness of this material with nitrogen to prevent developing and accelerate decomposing of thatch layer. The treatments included: the control, an American-made biological material (PHC)2, Iranian-made biological material, urea, sulfur coated urea, American-made biological material (PHC) + urea and Iranian-made biological material + urea. The experiment was carried out at the reserve turfgrass grounds of Azadi Stadium in Tehran (Iran) using, with mixture Turfgrass: (60%) Lolium prenne L. + (40%) Poa pratensis L.) during 2005. Thickness of the thatch, turfgrass height, root length, leaf color, total nitrogen, chlorophyll content, and C:N ratio were determined at the end of the experiment. The results showed that the thickness of the thatch was maximum in urea (34.55 mm) and minimum in PHC + urea (10.77 mm); plant height was max. in urea (15.08 cm) and min. in control (12.38 cm); leaf color was max. in control (8) and min. in PHC and sulfur coated urea (7); chlorophyll content was max. in urea (0.024%) and min. in control and PHC (0.014%)); C:N ratio was max. in control (16.57) and min. in urea (10.58) and total nitrogen content in urea was max. (4.6%) and min. in the control (2.98%). Treatments did not significant affect the root length of the turfgrass. Attention to results Iranian-made biological material + urea treatment is a suitable composition (due to low C:N ratio and comparison with control treatment thatch thickness is half in this treatment) for thatch control in turfgrass.