The relationship between the anatomical structure of the tomato fruit pericarp (Lycopersicon esculentum Mill.) and its mechanical properties

Abstract

The anatomical structure of the tomato (<i>Lycopersicon esculentum</i> Mill.) pericarp was studied in the fruits of five determinant field cultivars. The fruits of the examined cultivars differed in their mechanical properties. Fruits of cultivars which are firm and resistant to injury (Kecskemeti 886j-2, Campbell 28), moderately firm and resistant (Atma, Wenus) and soft, susceptible to injury (line No 155/84) were examined. The pericarp of the cultivars which have fruits resistant to injury had an approx. 200 µm thick covering layer (epidermis plus cuticle plus hypodermis) whereas that of fruits susceptible to injury was only 100 µm thick. In the fruits resistant to injury the cuticle penetrated deeply into the hypodermis, the epidermal cells were flattened and the hypodermis was composed of 4 - 5 rows of cells. The tomato fruits resistant to injury had a thick cuticle layer on their tangential walls - whereas those more susceptible had a thick cuticle layer on these walls.