عنوان مقاله [English]
نویسندگان [English]چکیده [English]
The use of such biostimulants as humic materials has recently become common in turf management operations. These products have been used to help the establishment of turfgrass and to enhance the turf stress tolerance capacity. This experiment was aimed at studying the effect of humic acid on some growth factors in turf grass. It was carried out in a factorial Randomized Complete Block Design (RCBD) of four replications and in controlled conditions. Turf seeds were sowed in polyethylene pots and following the establishment of the plants, they were monthly sprayed with Leonardite humic acid in concentrations of 0, 100, 400 and 1000 mg/L. Nine weeks past the start of treatments, such characteristics as height, fresh and dry weight, as well as the level of such elements as micro and macro nutrients were measured along with the visual quality of samples assayed. The results revealed that application of humic acid in concentrations of 100 and 400 mg/L were more effective than 1000 mg/L. The concentration of 100 mg/L positively affected the fresh and dry weight as well as the visual quality of the plants while the 400 mg/L concentration more profoundly affected K and Fe. The two concentrations of 400 and 1000 mg/L exerted a more serious effect on Zn content. None of these concentrations played any role on P content. An increase in humic acid concentration (1000 mg/L) caused a reduction in the height of the plants.