جذب پتاسيم و منيزيم در گياه ذرت ميكوريزايي تحت مقادير مختلف پتاسيم و منيزيم

Uptake Of Potassium and Magnesium in Mycorrhizal Maize Under Different Concentrations of Mg and K

Mycorrhizal colonization improve and increase the uptake of nutrients. In this research the effect of VAM (Vesicular- Arbuscular mycorrhiza) colonization on uptake of potassium and magnesium was studied. In this experiment natural soil containing spores of Glomus spp was used. Mycorrhizal spores were exposed to 4 concentrations of K solution, i. e. 240 (soil K content), 360 and 480 mg/L and 3 concentrations of Mg. i.e. 4.8 (soil Mg content). 7.2 and 9.6 meq/L concurrently. Plants were watered every 4 days for 16 days with 50 ml distilled water. A pot with sterilized soil was used as negative control. To study the mycorrhizal colonization, very thin longitudinal sections of plant roots (>lmm in diam.) were prepared manually and stained with lactophenol-cottonblue. Mycorrhizal percentage was determined by the grid-line intersect method. To measure Mg and K content atomic absorption method has been used. Mycorrhizal colonization increased Mg uptake but decreased K uptake. The maximum Mg content and minimum K content were observed in root and shoot when K (360 mg/L) and Mg (7.2 meq/L) were added to the pots concurrently. Regarding to interaction between VAM and these elements, by regulation of Mg and K in rhizosphere would increase mycorrhizal colonization in plants can be increased and through this way, plant nutrient status aiming resistance against stresses of environment can be changed.