EFFECTS OF MES [2(N-MORPHOLINO)-ETHANESULFONIC ACID] AND PH ON MINERAL NUTRIENT-UPTAKE BY MYCORRHIZAL AND NONMYCORRHIZAL MAIZE

Mycorrhizal (+VAM) and nonmycorrhizal (+VAM) maize (Zea mays L.) plant s were grown in sand culture in a greenhouse to determine effects of M ES [2(N-morpholino)-ethanesulfonic acid] (2.0 mM) and pH (4.0, 5.0, 6. 0, and 7.0) on mineral nutrient uptake. Plants were inoculated with th e vesicular-arbuscular mycorrhizal (VAM) isolate Glomus intraradices U T143. Shoot and root dry matter yields were lower in plants grown with MES (+MES) than without MES (-MES), and decreased as pH increased. Sh oot concentrations of N, Ca, Mg, Mn, and Zn were generally higher in MES than in -MES plants, and nutrient contents of most nutrients were generally higher in +MES than in -MES plants. Concentrations of N, Ca, Mg, and Mn increased and P, S, and Fe decreased, while contents of al l measured nutrients except Mn and Zn decreased as pH increased. Conce ntrations of Mn, Fe, Zn, and Cu were higher in +VAM than in -VAM plant s, and contents of P and Ca were higher in -VAM than in +VAM plants an d Zn content was higher in +VAM than in -VAM plants. MES had marked ef fects on mineral nutrient uptake which should be considered when MES i s used to control pH of nutrient solutions for growth of maize.