Secondary Growth in Dicot Root

Secondary Growth in Dicot RootVascular bundles in dicot roots are radial,exarch and mostly triarch.Vascular cambium is formed secondarily from conjuctive parenchyma cells lying just below phloem strand.Thus,the number of cambium strips formed equals the number of phloem strands.The cells of pericycle lying outside the protoxylem also become meristematic to form part of strips of cambium.These cambial strips join the first formed cambium strips to form complete,but wavy ring of vascular cambium.This cambium ring produces secondary xylem on inner side and secondary phloem on outer side.In roots,the growth rings are not distinct because there is no seasonal variation under the soil.From the outer layers of pericycle arises the phellogen which cuts phellem on the outer side and secondary cortex or phelloderm toward the inner side.
Author:- Ruby Parmar

This entry was posted in Arts. Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>