Studies on chemical constituents in n-butanol extracts from epicarp of green fruit of Juglans mandshurica Provenance Selection of Juglans mandshurica Maxim. and the Effects of Environmental Factors Regeneration System for Axillary Bud of Juglans mandshurica Maxim. Induction of Embryogenic callus and Somatic Embryogenesis of Juglans mandshurica Maxim. Chemical constituents from bark of Juglans mandshurica Embryology of Juglans mandshurica Maxim.(Ⅰ) the Microsporogenesis,and the Development of Male Gametophytes