Morphometric and biochemical characterization of old low-chilling pear cultivars (pyrus communis l.) Grown in Tunisia

Abstract

Fruit quality attributes were studied in eight old pear cultivars grown in a Mediterranean climate in the Centereasternof Tunisia. Fruit quantitative and qualitative morphological parameters, fruit skin color on both sunexposedand shaded fruit sides, and chemical characteristics in both flesh and peel (titratable acidity, TSS, fructose,glucose, sucrose, total sugars, citric and malic acids) were evaluated. A high variability was found in the set of theevaluated pear cultivars. The fruit weight varied from 22.63 g to 63.72 g and firmness varied from 2.78 kg/cm2and 4.78 kg/cm2. ‘Arbi Sidi Bou Ali’ and ‘Arbi Bouficha’ presented the biggest fruits. However, ‘Radsi’ tendedto have the smallest fruits. ‘Jrani’ and ‘Arbi Chiheb’ have shown the lowest values of healthy seeds per fruit.‘Radsi’ pears were the most red-colored fruits, while ‘Jrani’ ‘Arbi Chiheb’ and ‘Arbi Bouficha’ produced greenyellowishfruits. Results showed also that pear fruit flesh had more effective sugars and organic acids comparedto peel for all cultivars. The TSS ranged from14.6° brix to 19.1°Brix in the flesh and from 12 to 17.1°Brix in thepeel. ‘Arbi Chiheb’ was distinguished by the highest malic acid content in both flesh and peel. Titratable aciditywas significantly higher in ‘Arbi Sidi Bou Ali’, ‘Tourki’ and ‘Meski Arteb’ compared to other cultivars. A highcorrelation was found among some pear quality attributes, which could reduce the number of pomological traits.These results would be a guide in the selection of potential cultivars which are used in food industry and freshmarket as well as in breeding programs.