Investigation on Genetic Diversity in Mahaleb(Prunus mahaleb L.) Populations Using Morphological Characters

Prunus mahaleb L. and Prunus avium L. are the principal rootstocks used in Iran and many other countries for sweet and sour cherries. This study was conducted at Agricultural and Natural Resources Center of Khorasan with the main purpose of investigation of genetic diversity and identification of mahaleb dwarf genotypes for cherry rootstock breeding. Morphological characters of 17mahaleb populations were evaluated. One-way analysis of variance was performed for determination of genetic diversity of different regions which indicated significant differences for most traits. Factor analysis revealed that in the first factor, crown height, size index, crown width, trunk circumference and crown volume had highest factor loading, bark to wood ratio, internode and chlorophyll content were the second most important and third factor was leaf area. These factors contained 57.9 percent of total variance. There were significant correlations between tree vigor, crown width, and crown volume and size index. Results also showed that mahaleb seedlings had vigor variation. Therefore, mahaleb seedlings were classified into four groups, very dwarf, dwarf, semi dwarf and standard at the basis of size index.