Genotypic and phenotypic diversity in guava (Psidium guajava']java L.) genotypes from Iran

Introduction - Guava, an important fruit crop worldwide and in southern Iran, is believed to have originated from Central America. However, the extant of diversity in the most guava producing regions is poorly understood. Materials and methods - Seventy-nine morphological parameters, along with nine simple sequence repeat markers were used to characterize the genetic relations of 20 guava genotypes in Iran. Results and discussion - Principal component analysis for the first and second components explained 53.58% of the variability among the genotypes. The number of alleles per locus ranged from 2 to 4 with an average of 3 alleles per locus. The mean expected and observed heterozygosity over 8 polymorphic SSR loci were 0.62 and 0.67, respectively. Conclusion - The studied individuals were divided based on their fruit shape and pulp color, and hence, our assumption that the genotypes would be grouped according to their fruit characteristics was verified. SSR markers allowed us to monitor the studied individuals. Therefore, genotypes with pink pulp (and round fruits) were separated from those that had white pulp (with pyriform or ellipsoid fruits) by both molecular and morphological data.