Role of Stem Growth in Linum Usitatissimum Leaf Trace Patterns

Linum usitatissimum stem growth parameters were quantified by computer‐assisted analyses of scanning electron micrographs of shoot apical meristems throughout ontogeny. There were progressive decreases in the plastochron and relative plastochron rates of radial and vertical stem growth which resulted in the generation of progressively higher orders of contact parastichy phyllotaxis throughout ontogeny. The change in the relative spacing of primordia initiation on the stem coupled with the iterative differentiation of leaf gap and interfascicular ray parenchyma associated with each leaf primordium resulted in the delimitation of progressively higher orders of leaf trace interconnections throughout ontogeny. A set of developmental rules was generated which should permit simulation of many leaf trace patterns.