Quantification and Allelopathy Potential of Phenolic Acids in Aqueous Extracts of Legumes A FEW QUESTIONS ON RADIATION BREEDING FOR HERBAGES Effects of Growing Different Herbages on Soil Water-Holding of a Non-irrigated Apple Orchard in the Weibei Area of the Loess Plateau Study on technology of multidimensional grassland establishment in semi-arid Loess Hill Region