Decrease in nitrate uptake and increase in proton release in zinc deficient cotton, sunflower and buckwheat plants

摘要: The effect of varied Zn supply on the pH nutrient solution and uptake cations anions was studied in cotton (Gossypium hirsutum L.), sunflower (Helianthus annuus L.) buckwheat (Fagopyrum esculentum Moench) plants grown under controlled environmental conditions solutions with nitrate as source nitrogen. With appearance visual deficiency symtoms, decreased from 6 to about 5 whereas increased 7 when were adequately supplied Zn. In deficient decrease associated a shift cation-anion ratio favour cation uptake. Of major ions, Ca2+ K+ either not affected or only slightly lowered NO3 - drastically plants. Although nutritional status hardly concentrations plants, leakage roots into diluted CaCl2 nearly 10 times higher than that contrast deficiency, Mn neither nor solution. results indicate that, probably consequence role plasma membrane integrity nitrogen metabolism, is dicotyledonous species net particularly depressed which turn an increase corresponding external pH. ecological relevance this rhizosphere acidification discussed.