Importance of the post-mitotic isodiametric growth (PIG) region for growth and development of roots

摘要: Plant cells are assumed to embark on rapid elongation immediately after the cessation of their mitotic divisions at proximal end meristem. However, a comprehensive appraisal most data previously published this matter, as well several recently obtained findings, has convincingly revealed, least for root that belief is incorrect. For example, morphometric analysis maize apex clearly defined distinct transitional region between meristem and zone cell elongation. This growth operationally post-mitotic isodiametric (PIG) region. In middle cortex, may have length similar in steady-state growing roots. We believe PIG specific phase ontogeny more common with meristematic than rapidly elongating cells, although many metabolic properties rather unique. regard, certain region, such distributions microtubules sensitivity towards auxin calcium, were found be crucial importance induction differential patterns essential graviresponse Other indicate considerable significance overall development roots because its characteristic plasticity under unfavourable external conditions.