HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Booysen, P. deV. Articles by Nelson, C. J. Search for Related Content PubMed Articles by Booysen, P. deV. Articles by Nelson, C. J. Agricola Articles by Booysen, P. deV. Articles by Nelson, C. J.

Leaf Area and Carbohydrate Reserves in Regrowth of Tall Fescue¹

Four combinations of low and high levels of watersoluble carbohydrate (WSC) reserves (LC, HC) and residual leaf area (LL, HL) were evaluated in terms of vegetative regrowth in a controlled environment at 20 C. HL contributed more than did HC to relative growth rate and to total plant size at the end of a 20-day regrowth period. Rate of increase in leaf area was similar for plants with HL or HC or both. LC/LL plants did not rapidly replenish WSC, and produced leaf area at a slower rate. In LL plants, irrespective of WSC content, leaf area was produced initially at the expense of stored carbohydrate energy. Leaf growth was the dominant sink throughout the 20-day period in LC/LL; whereas by day 15, HC/LL had reached the photosynthetic entity, the point at which the relative rate of increase in leaf area was the same as for total plant weight. In HL, again irrespective of WSC level, leaf growth was dominant initially, but by day 5 the photosynthetic entity had been reached. New tiller formation was lowest in the LC/LL treatment and was increased by HC, and especially by HL. After 20 days, weight of WSC in the stubble plus roots was highest in the HC/HL treatment, followed by LC/HL, HC/LL, and LC/LL, respectively. It is apparent that both residual leaf area and reserve carbohydrates contribute energy to regrowth of grasses, and that severity of defoliation affects the dependence of regrowth on stored energy.

Key Words: Tillering • Relative growth rate • Relative leaf growth rate • Festuca arundinacea Schreb.

² Formerly research associate, (now professor in pasture sci., U. of Natal, Pietermaritzburg, Republic of South Africa) and associate professor, Dept, of Agron., U. of Mo., Columbia, MO 65201.

Received for publication July 19, 1974.

This article has been cited by other articles:

				J. M. Lee, D. J. Donaghy, and J. R. Roche Effect of Defoliation Severity on Regrowth and Nutritive Value of Perennial Ryegrass Dominant Swards Agron. J., February 26, 2008; 100(2): 308 - 314. [Abstract] [Full Text] [PDF]

				D. J. Donaghy, L. R. Turner, and K. A. Adamczewski Effect of Defoliation Management on Water-Soluble Carbohydrate Energy Reserves, Dry Matter Yields, and Herbage Quality of Tall Fescue Agron. J., January 11, 2008; 100(1): 122 - 127. [Abstract] [Full Text] [PDF]

				L. R. Turner, D. J. Donaghy, P. A. Lane, and R. P. Rawnsley Changes in the Physiology and Feed Quality of Prairie Grass during Regrowth Agron. J., September 5, 2006; 98(5): 1326 - 1332. [Abstract] [Full Text] [PDF]