• Corpus ID: 88818990

Secondary growth of the stem of Celosia argentea L. and Aerva sanguinolenta (L.) BLUME (Amaranthaceae)

@inproceedings{Rajput2001SecondaryGO,
  title={Secondary growth of the stem of Celosia argentea L. and Aerva sanguinolenta (L.) BLUME (Amaranthaceae)},
  author={Kishore S. Rajput},
  year={2001}
}

• K. Rajput
• Published 2001
• Environmental Science

Structure and development of vascular cambium was studied histologically in the stem of Celosia argentea L. and Aerva sanguinolenta (L.) BLUME (Amaranthaceae). In both the species secondary growth resulted in the development of successive rings of cambia. The cambium is storied consisting only of fusiform initials giving rise to rayless vascular tissues at least in the early part of secondary growth. In the later part of the secondary growth, development of vertically elongated rays were observed in Celosia argentea. Each successive ring of cambium developed from the axial parenchyma at a distance of about four to six cell layers external to the phloem produced by the previous cambium. Functionally the cambium was bi-directional producing xylem centripetally and phloem centrifugally. Developmentally each cambium ring was divided into two distinct types : i. small segments of cambium producing conducting elements of xylem and phloem, and ii. wider segments of cambium giving rise to thick-walled conjunctive tissues centripetally and thin-walled parenchyma centrifugally in Aerva sanguinolenta and thin-walled parenchyma on both xylem and phloem side in Celosia argentea. This variation in cambial behavior resulted in the formation of successive rings of xylem alternating with phloem and axial parenchyma in Aerva sanguinolenta and vascular bundles embedded in ground mass of axial parenchyma in Celosia argentia.