Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

Assessment of Enzyme Induction and Aerenchyma Formation as Mechanisms for Flooding Tolerance in Trifolium subterraneum 'Park'

SAMIRA ASCHI-SMITI, WIDED CHAÏBI, RENAUD BROUQUISSE, BÉRÉNICE RICARD and PIERRE SAGLIO
Annals of Botany
Vol. 91, No. 2, SPECIAL ISSUE: Flooding and Plant Growth (January 2003), pp. 195-204
Published by: Oxford University Press
Stable URL: http://www.jstor.org/stable/42801211
Page Count: 10
  • Download ($42.00)
  • Cite this Item
Assessment of Enzyme Induction and Aerenchyma Formation as Mechanisms for Flooding Tolerance in Trifolium subterraneum 'Park'
Preview not available

Abstract

The objective of this study was to evaluate the role of enzyme induction and aerenchyma formation in prolonged tolerance to soil flooding in a variety of underground clover (Trifolium subterraneum 'Park') previously selected for resistance. Seedlings were grown in hydroponic tanks, initially with aeration for 3 weeks and subsequently in the absence of aeration for up to 3 weeks. After 1 h in the absence of aeration, the oxygen concentration in the hydroponic medium had decreased to 1-5 %. During the 3 weeks of extreme oxygen deficiency, primary roots died and were replaced by considerable numbers of adventitious roots. Activities of many glycolytic and fermentative enzymes increased in adventitious roots. Excised adventitious roots were capable of immediate induction of ethanol in the absence of lactate production, in association with energy charge higher than that in excised roots of aerobically maintained controls. Energy charge was even higher when measured in adventitious roots in planta. Interestingly, haemoglobin protein could be correlated with energy charge. Aerenchyma was readily visualized in adventitious roots by optical microscopy of longitudinal and transverse sections. We conclude that avoidance of root anoxia via aerenchyma is the major mechanism for prolonged root tolerance in Trifolium subterraneum 'Park'.

Page Thumbnails

  • Thumbnail: Page 
[195]
    [195]
  • Thumbnail: Page 
196
    196
  • Thumbnail: Page 
197
    197
  • Thumbnail: Page 
198
    198
  • Thumbnail: Page 
199
    199
  • Thumbnail: Page 
200
    200
  • Thumbnail: Page 
201
    201
  • Thumbnail: Page 
202
    202
  • Thumbnail: Page 
203
    203
  • Thumbnail: Page 
204
    204