Genetic and morphological relationships between possible Italian and ancestral cultivars of Persimmon

A set of 18 persimmon (Diospyros kaki L.f.) cultivars (representing 11 ancestral varieties and 7 presumed Italian accessions) and 2 related species (Do lotus L. and D. virginiana L.) were used to assess their phenotypic and genetic distances by analysing morphological traits and applying RAPD markers. Quantitative morphological data (39 continuous variables of shoots, leaves, flowers, fruits and seeds) were standardised. and a principal components analysis was performed for the first set of data. The 12 principal components (eigenvalue>1) were used to calculate the quantitative morphological distance between accessions. The qualitative distance matrix was calculated on 28 discontinuous variables observed in the same organs. The genetic Euclidean distances were assessed by applying the RAPD technique, after DNA extraction from young leaves and the amplification with 4 different primers which allowed to individuate 142 markers. The relationships among the 20 genotypes were represented by three dendrograms constructed on the distance matrixes. All accessions have been distinguished by the three different approaches. Separate clusters for the possible Italian accessions and the ancestral cultivars were clearly individuated on dendrograms based on morphological traits. A more complex distribution of accessions was observed on the dendrogram built on RAPD markers. The simple correlation coefficient was low (r = 0.57) between the two morphological distance matrixes and extremely low between the genetic distance matrix and the biometric (r = 0.15) and qualitative (r = 0.02) distance matrixes.