The Components of Fruit Size In Pomegranate

Pomegranate (Punica granatum) fruit is valued for its flavorful, juice-containing arils, and is consumed and marketed as whole fresh fruit, extracted arils, juice, syrup (grenadine), wine, teas, and seed oil. The size of fruits produced within commercial orchards can be quite variable even from trees of the same genotype grown under similar cultivation practices.  With market-price premiums for large-sized fruits and producer-targeted traits including high total aril weight and high juice content, understanding fruit attributes is important.  Although pomegranates have been cultivated since antiquity, fruit attributes, particularly those related to size are poorly defined.  In this study, Wonderful variety flowers were tagged at petal opening, and at maturity the same-aged fruits were evaluated.  Fruit compositional changes including fruit volume and weight, aril weight and number, pericarp weight, seed weight, and juice/pulp content were evaluated in fruits which had a wide range of sizes. Correlations between fruit characteristics were determined, and factor analysis was used to establish fruit and aril indexes. Results indicated that because fruit volume, fruit weight, and total aril weight are closely correlated, any single character can be used as a common indicator of fruit quality.  The number of arils per fruit was highly correlated with fruit size, with larger fruit containing greater numbers of arils.  This is in contrast to individual average aril weight which showed no significant relationship to fruit size.  Thus, crop production strategies that result in increased aril number per fruit will result in bigger fruits with greater total aril weight.