Phenotypic flexibility and drought avoidance in taro (Colocasia esculenta (L.) Schott)

  • Carla S. S. Gouveia
  • José F. T. Ganança
  • Humberto G. M. de Nóbrega
  • José G. R. de Freitas ISOPlexis Genebank, Faculty of Life Sciences, University of Madeira, Campus da Penteada, 9020-105, Funchal, Madeira, Portugal
  • Vincent Lebot CIRAD-BIOS, PO Box 946, Port Vila, Vanuatu
  • Miguel Â. A. Pinheiro de Carvalho ISOPlexis Genebank, Faculty of Life Sciences, University of Madeira, Campus da Penteada, 9020-105, Funchal, Madeira, Portugal

Abstract

Taro (Colocasia esculenta (L.) Schott) is a substantial staple food in most of the tropical regions. Prolonged exposure to drought impairs crop production worldwide. Tolerant crops have the best capability to cope and avoid drought, through phenotypic flexibility mechanisms. The water use efficiency (WUE) is well known in taro crops, but very scarce information is available relating to their nutrient efficiency (NER) in drought conditions. Our work provided pertinent information about the physiological variation of seven taro accessions subjected to seven months of drought, by recording the differences for nutrient allocation, chlorophyll canopy, biomass loss, and stress intensity. Significant relationships between control and drought treatments on WUE (+85%), total plant biomass (TPB, -26.8%), chlorophyll content index (CCI, +1.8%), and nutrient harvest index (NHI, +0.2%) were detected. Drought led to a generalized loss of TPB as drought avoidance strategy, although distinct phenotypic flexibility was observed through the root:shoot ratio (R:S) and stress index (SI) from the corm and shoot organs. The nutrient allocation from the corms to shoots, with NER increase registered in drought conditions, can be a valuable tool to complement the TPB and WUE productivity traits, to be used in taro breeding programs.

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How to Cite
Gouveia, C. S. S., J. F. T. Ganança, H. G. M. de Nóbrega, J. G. R. de Freitas, V. Lebot, and M. Â. A. P. de Carvalho. “Phenotypic Flexibility and Drought Avoidance in Taro (Colocasia Esculenta (L.) Schott)”. Emirates Journal of Food and Agriculture, Vol. 32, no. 2, Mar. 2020, pp. 150-9, doi:https://doi.org/10.9755/ejfa.2020.v32.i2.2075. Accessed 7 June 2020.
Section
Research Article