Impressive arrays of morphophysiological and biochemical diversity of pomegranates in Arasbaran; a hidden pomegranate paradise

Although the Arasbaran region has one of the richest genetic reserves of pomegranate in the world, the scopes of this diversity still remains largely unknown. In this research, we collected 19 different pomegranate ecotypes from the Arasbaran region, and studied them in terms of important morphophysiological and biochemical traits, such as fruit diameter and weight, peel weight, juice content, polyphenol and flavonoid contents, and antioxidant activity. The results showed an extraordinary diversity between ecotypes in the evaluated traits. For instance, phenolic and flavonoid contents varied between 21.5–61.5 mgGAL/L and 6–12.5 mgQE/L, respectively. Highly significant differences among ecotypes were also noticeable in the antioxidant activity with the IC₅₀ ranging between 33.70 and 103.85 µg/mL. Our investigations showed that desirable traits in terms of human nutrition and industrial marketability are spread among different ecotypes, and therefore, one particular ecotype cannot be introduced as the superior one. However, here we present a new method to evaluate pomegranates according to important physiological and biochemical characteristics, facilitating the screening of pomegranates to select superior ecotypes. Our results, in addition to identifying and preserving unique pomegranate genetic resources, can play an important role in expanding breeding programs and sustainable production and cultivation of superior pomegranate cultivars.