Effect of different calcium compounds on postharvest quality of apples
Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences,Kreutzwaldi St. 64, EE51014 Tartu, Estonia, e-mail: email@example.com
The research was conducted with apple (Malus domestica Borkh.) cultivars ‘Antei’ and ‘Talvenauding’ in the Rõhu Research Centre and the Estonian University of Life Sciences in 2005–2006. The aim of the study was to determine the influence of different Ca compounds (CaCl2, Ca(NO3)2 and Boramin Ca) used as preharvest sprays on the mineral content of appleleaves and fruits and apple postharvest quality. Apples were stored in normal atmosphere at 2–5ºC and 80–85% RH. The storage time for ‘Talvenauding’ was 5 months and for ‘Antei’ 6 months. The percentage of spoiled apples was calculated monthly. The content of Ca, N, P, K and Mg from apple leaves was determined at the end of August and from fruits after the harvest. The average effect of calcium treatment was significant only in the variant where Ca (NO3)2 +CaCl2 were used: the percentage of spoiled fruits was 25% compared to 39% in the controlvariant. Correlation analysis showed that the amount of spoiled fruits in January and at the end of storage had negative correlations with content of Ca in leaves and content of Mg in fruits. At the same time positive correlations were found between N-, P-, K- and Ca content of fruits and spoilage. Only the increasing fruit Mg had a positive effect on apple fruit quality in the present experiment. The content of mineral elements in leaves had no positive correlation with the content of mineral elements in fruits.