Variability of some traits of walnuts (Juglans regia L.) in the test of half sib, originating in the Djerdap forest

Abstract

As part of efforts for protection and restoration of variability of Juglans regia in Djerdap gorge, Serbia, where it grows as autochthonous relict species, the variability of ten measured and nine derived leaf morphometric parameters of half-sib progenies Persian walnut originating from Djerdap gorge was studied in this work. According to the contribution to total expected variance, parameters that were most effected by differences between half-sib progenies are leaf width (LW), side leaflet length (lL) and top leaflet length (20-30%). Using loadings with the first four rotated principal components, describing 90.1% of total variance, all parameters were grouped in four groups, where parameters LW, lL and lt were in the first group, suggesting multicollinearity between them. These parameters had also relatively high loadings with the first canonical variable from canonical discriminant analysis. Only one of them (lt) was selected by forward stepwise discriminant analysis, where model with four selected leaf parameters achieved 26.5% of correct allocation, while model with all studied parameters achieved 62.4% of correct allocation. Half-sib progenies agglomerated in three clusters, where two small clusters originate from trees that were close to sheltered valleys of small tributaries to river Danube, opposite to mother trees of the first cluster progenies, that were exposed to dominant winds.