Quality and fruit colour change in Verna lemon

  • Ignacio Porras Murcian Institute of Agriculture and Food Research and Development (IMIDA).
  • Jose Manuel Brotons Miguel Hernandez University
  • Agustín Conesa Miguel Hernandez University
  • Ramón Castañer Miguel Hernandez University
  • Olaya Pérez-Tornero Murcian Institute of Agriculture and Food Research and Development (IMIDA).
  • Francisco Javier Manera Miguel Hernandez University
Keywords: Verna, rind colour, HunterLab, minimum temperatures, degreening

Abstract

While most of lemon cultivars in the northern hemisphere are harvested in autumn-winter, Verna, an autochthonous Spanish cultivar, is harvested later (February to August), supplying the European market when lemons are in short supply, a market that is also served by imports from the southern hemisphere, mainly Argentina and South Africa. The aim of this study was to determine the temperature at which degreening begins naturally in Verna lemon, noting the evolution of colorimetric parameter a and comparing the same with the equivalent measurements made in Eureka lemon, the most widely cultivated lemon worldwide. The influence of solar radiation on the colorimetric parameters was studied, and then the influence of the minimum temperatures on the change from green to yellow, using the data collected over five growing seasons, was also assessed. The results confirmed the relation between net solar radiation and degreening in Verna, a process that begins when net solar radiation reaches a value of between 2 and 4 MJ/m2.day and when the mean temperature of the 14 days prior to sampling is8.8 ºC or when the daily mean temperature reaches5.5 ºC on two consecutive days. The information obtained will enable growers to predict the colour changes that will occur in the field and potential growers to ascertain whether a given geographical zone is suitable for the crop in question. 

Author Biographies

Ignacio Porras, Murcian Institute of Agriculture and Food Research and Development (IMIDA).

Department of Citriculture, Murcian Institute of Agriculture and Food Research and Development (IMIDA). La Alberca. Murcia, Spain

Jose Manuel Brotons, Miguel Hernandez University

Department of Economic and Financial Studies. Miguel Hernandez University, Elche. Alicante, Spain

Agustín Conesa, Miguel Hernandez University
Department of Vegetable Production and Microbiology. Miguel Hernandez University, Orihuela. Alicante, Spain
Ramón Castañer, Miguel Hernandez University
Department of Physics and  Computer Architecture. Miguel Hernandez University, Orihuela.
Olaya Pérez-Tornero, Murcian Institute of Agriculture and Food Research and Development (IMIDA).
Department of Citriculture, Murcian Institute of Agriculture and Food Research and Development (IMIDA). La Alberca. Murcia, Spain
Francisco Javier Manera, Miguel Hernandez University

Department of Physics and  Computer Architecture. Miguel Hernandez University, Orihuela. Alicante, Spain

Published
2015-10-06