Carbon balance in grapevines under different soil water supply: importance of whole plant respiration

Authors

  • J.M. ESCALONA,

    Corresponding author
    1. Biology Department, Research Group of Plant Biology under Mediterranean Conditions, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Baleares, Spain
      Dr José Mariano Escalona, fax 00 34 971 173184, email jose.escalona@uib.es
    Search for more papers by this author
    • Both authors contributed equally to the present work.

  • M. TOMÀS,

    1. Biology Department, Research Group of Plant Biology under Mediterranean Conditions, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Baleares, Spain
    Search for more papers by this author
    • Both authors contributed equally to the present work.

  • S. MARTORELL,

    1. Biology Department, Research Group of Plant Biology under Mediterranean Conditions, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Baleares, Spain
    Search for more papers by this author
  • H. MEDRANO,

    1. Biology Department, Research Group of Plant Biology under Mediterranean Conditions, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Baleares, Spain
    Search for more papers by this author
  • M. RIBAS-CARBO,

    1. Biology Department, Research Group of Plant Biology under Mediterranean Conditions, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Baleares, Spain
    Search for more papers by this author
  • J. FLEXAS

    1. Biology Department, Research Group of Plant Biology under Mediterranean Conditions, Ctra Valldemossa, km 7.5, 07122 Palma de Mallorca, Baleares, Spain
    Search for more papers by this author

Dr José Mariano Escalona, fax 00 34 971 173184, email jose.escalona@uib.es

Abstract

Background and Aims:  Net carbon gain commonly estimated from leaf photosynthesis measurements often overestimates grapevine production. This is usually attributed to canopy complexity and a lack of plant respiration data. The present study evaluates the significance of plant respiration in correcting this overestimation.

Methods and Results:  Non-grafted and non-productive young plants of four grapevine varieties were grown either under irrigation or controlled water stress for 30 days. Daily time courses of leaf photosynthesis and transpiration were determined along with measurements of leaf, stem and root respiration, from which whole plant carbon balance was estimated. Up to 30–60% of carbon obtained by photosynthesis is used in respiration, with root respiration being the largest user of fixed carbon (up to 75%).

Conclusions:  Whole plant respiration represents a significant part of total carbon balance and accounts for the largest part of the discrepancy between photosynthesis-based estimates of plant production and actual plant production.

Significance of the Study:  The present study presents a quantitative evaluation of the importance of plant respiration in grapevine carbon balance and biomass production, highlighting that gas exchange studies aiming predict plant production should include estimates of respiration, especially of roots.

Ancillary