A Study on the Characteristics of the Growth and the Biomass of Clonal Ramets in Rhus typhina The influence of volatiles of three invasive plants on the roots of upland rice seedlings Involvement of Hydrogen Peroxide Generated by Polyamine Oxidative Degradation in the Developmentof Lateral Roots in Soybean Xylem hydraulic traits of Populus euphratica Oliv. in extremely drought environment