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 Google Scholar Google Scholar Articles by Hall, M. H. Search for Related Content PubMed Articles by Hall, M. H. Agricola Articles by Hall, M. H.

Alfalfa Growth Following Release from Drought Stress

M.H. Hall, Dep. of Agronomy, Pennsylvania State Univ., University Park, PA 16802

^* Corresponding author

Compensatory growth (increased growth relative to normal) of alfalfa (Medicago sativa L.) when released from periods of drought stress has been observed or suggested. The objective of this research was to determine whether such compensatory growth does occur. Alfalfa was subjected to drought stress (plant water potential < - 1.5 MPa) for and 4 wk in a greenhouse study and 2, 4, and 6 wk in a field (Palouse silt loam soil, fine-silty, mixed, mesic Pachic UItic Haploxerolls) study near Moscow ID. Following harvest and removal of the droughts stress, plant growth measurements were made after 30 d of growth in the greenhouse and biweekly during 5 wk of growth in the field. At the conclusion of the growth periods in both greenhouse and field studies, average stem length and dry matter yield of previously drought-stressed plants were 88 and 91%, respectively, compared with previously unstressed plants. Stem growth rates of field grown plants were less for the previously stressed plants only during the first 2 wk after release of stress. Stress treatments did not affect stems per plant (greenhouse) or stems per square meter (field). Leaf area per stem, however, for the previously drought-stressed plants was 122 and 108% compared with previously unstressed plants in the greenhouse and field, respectively. Leaf area was greater in the growth period following drought stress, but stem length and dry matter yield were reduced. Previous observations of apparent compensatory alfalfa growth after a drought may be attributed to increased leaf area.

Received for publication August 31, 1992.