New report on anatomy of lenticel development in Fraxinus (Oleaceae) species from Iran

摘要

The adaptive abilities of plants allow them to survive in wide ranges of physicalconditions. These adaptations appeared to be associated with lenticels. Lenticels are essentialto the plants, since they control gas exchange in the absence or losing the function of stomas.Fraxinus is a morphologically variable genus and this is regarded as individual adaptations toenvironmental conditions. Plant adaptations to different environmental conditions can alsoinfluence their anatomical structures. In present study, the anatomical features of leaf petiolesand fruits were examined in two Fraxinus species from Iran. Samples of young to mature petioleand fruit samples were collected from the trees. The anatomical observations revealed differentorigins of lenticel development which are recorded for the first time. Lenticels on the petioleshave epidermal origin however lenticels on the fruits are originated from stomas.