Effects of Exogenous Nitric Oxide on Embryo Germination and ROS Accumulation in Seedling Growth Initial Stage of Sorbus pohuashanensis Outcrossing Rates in 6 Natural Populations of Sorbus pohuashanensis Cytological and Histological Investigations on Somatic and Zygotic Embryogenesis of Sorbus pohuashanensis Sorbus pohuashanensis seed dispersal and germination and their relationships with population natural regeneration. Geographical Distribution and Patterns of Natural Regeneration of Sorbus pohuashanensis Somatic Embryogenesis from Mature Zygotic Embryo Explants of Sorbus pohuashanensis Hedl Natural regeneration characteristics of Sorbus pohuashanensis in forest region of eastern Northeast China. Physiological Adaptation of Sorbus pohuashanensis Seedlings to Heat Stress The Rapid Propagation Technology of Sorbus pohuashanensis by Axillary Bud Regeneration Way THE TYPE AND EVOLUTION OF VASSEL ELEMENT‘S PENFORATION PLATE OF SORBUS POHUASHANENSIS