Involvement of abscisic acid and other stress indicators in taro (Colocasia esculenta (L.) Schott) response to drought conditions

• Autor(a) principal: Gouveia, Carla S. S.
• Data de Publicação: 2020
• Outros Autores: Ganança, José F. T., Slaski, Jan J., Lebot, Vincent, Carvalho, Miguel Â. A. Pinheiro de
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.13/3665
• topic: Carbon isotope; Chlorophyll content index; Drought stress; Enzyme-linked immunosorbent assay; Oxalic acid; Water use efciency; .; Faculdade de Ciências da Vida

Taro (Colocasia esculenta (L.) Schott) is a staple food and represents an important food security role in most tropical regions. It is, unfortunately, susceptible to prolonged drought conditions. Abscisic acid (ABA) is a well-documented stress-induced phytohormone that tolerant crops usually accumulate in leaves to induce stomatal closure, preventing water loss through inhibition of transpiration. Hitherto, exists very scarce information regarding the ABA role in taro response to drought. Here, we determined the ABA content in the shoots and corms of taro subjected to seven months of water scarcity and linked ABA to other drought resilience traits, including carbon isotopic discrimination (Δ13C), oxalic acid (OA), chlorophyll content index (CCI), water use efciency (WUE), and biomass (B). The Δ13C-shoot content showed partially open stomata in all accessions, and signifcant correlation with Δ13C-corm, CCI, and WUE. The osmotically active OA-shoot decrease seemed not to interfere with the stomatal aperture. The tolerant accessions subjected to drought stress had higher B-corm, ABA shoot, Δ13C-shoot, CCI, OA, and WUE. However, the observed under drought conditions increase of ABA in the shoots, and its decrease in the corms were not signifcantly correlated, nor with other traits, suggesting that ABA was not the main regulator of taro physiological processes under stress. The information gained should be considered in breeding programs to predict taro’s response to climate change.