Changes in nutritional homeostasis of Poncirus trifoliata and Ceratonia siliqua as a response to different iron levels in nutrient solution

Abstract

Iron (Fe) deficiency is a nutritional disorder in plants. Poncirus trifoliata is susceptible to Fe deficiency, but symptoms of Fe deficiency are rare in Ceratonia siliqua, a slow-growing species. Specimens of the two species were grown in nutrient solutions containing three Fe concentrations: without Fe (0 µM), 1 µM Fe, and either 10 µM Fe (for Ceratonia) or 40 µM Fe (for P. trifoliata). Growth, the degree of chlorosis, the plant mineral composition, and the activity of the root ferric chelate-reductase (FCR) were assessed. Ceratonia plants exposed to 1 µM Fe were efficient at using Fe in the synthesis of chlorophyll. The activity of FCR was enhanced in the total absence of Fe. In Poncirus a low activity of the FCR was observed in plants with no Fe. The balance between micronutrients in the Ceratonia roots was not affected with 1 µM Fe compared with the higher Fe concentration treatments.

Keywords:

• carob
• citrus
• iron chlorosis
• nutrients ratios
• rootstocks

Disclosure statement

The authors declare that they have no conflict of interest.

Additional information

Funding

This study was funded by the FCT (Foundation for Science and Technology) national project PTDC/AGR-ALI/100115/2008, by FEDER through the Operational Programme for Competitiveness Factors, COMPETE, and as part of the FCT strategic project PEst-C/AGR/UI0115/2011.

Notes on contributors

Pedro José Correia

Pedro José Correia and Maribela Pestana developed the ideas and designed experiments. Pedro José Correia wrote the manuscript; Florinda Gama and Teresa Saavedra gave technical support, collected, and analyzed data together with Pedro José Correia and Maribela Pestana. Amarilis de Varennes performed mineral analysis and gave conceptual advice. All authors contributed to improving paper and approved the final manuscript.