The Distribution of Dry Matter in Bean Seedlings in Light and Darkness Conditions

摘要: Plants express different stages of development to complete their life cycle, where in each phase have demands on nutrition and the distribution photosynthates among structures. Thus, during growth, plant accumulates allocates proportions dry matter structures root. In seed is embryo formed by radicle plumule, cotyledons. They stored nutrient reserves that proportion originate root plumule forms stem leaves seedling. The seeds can contain one cotyledon as monocotyledons such maize, two dicotyledonous plants beans many cotyledons gymnosperms. seedling hypocotyl located between epicotyl which includes above a bean are defined system consists main root, adventitious roots, primary secondary tertiary roots hypocotyl, cotyledons, epicotyl, simple leaves, first trifoliate leaf second leaf. Each structure complies with specific functions maintain growth development. absorb water minerals vegetative part absorbs solar radiation produce photosynthate nourish germination resumes activating metabolism embryo, occurs when available around them ends specifically embryonic elongates (Bidwell, 1990; Mayer Poljakoff, 1989). From practical standpoint, it considered has emerged from shell this moment During biochemical morphological processes perform marks beginning decline exportation, accompanied an increase respiration (Bathellier et al., 2008). appears radicle, grows down, then hook emerges comes into contact light so soon chlorophyll actives triggers photosynthesis. After germination, begins, leads establish ranging ground until becomes autotrophic (Holman Robbins, 1982). light, seedlings quickly initiate synthesis