Influence of Osmotic Stress on the Lipid Physical States of Plasma Membranes from Wheat Roots Experiments on Characteristics of Wheat Roots Difference between Apple-wheat Intercropping System and Wheat Monoculture System Spatial and Temporal Distribution Characteristics of Wheat Roots in Apple-wheat Intercropping EFFECT OF MET ON FORMATION AND VIGOR OF WHEAT ROOTS Osmotic Adjustment in Wheat Roots and Hydrolysis of Starch in Root-cap of Wheat under Osmotic Stress STUDY ON MATERIAL FLOW OF WHEAT ROOTS USING ISOTOPE TRACERS Influence of Different Concentrations of NO-3 and NH+4 on the Activity of Glutamine Synthetase and Other Relevant Enzymes of Nitrogen Metabolism in Wheat Roots