Assessment of genetic diversity in Moroccan fig (Ficus carica L.) collection by combining morphological and physicochemical descriptors

Abstract

There are not many exhaustive works emphasizing the amount of genetic diversity based on multivariate analysis of a large sample of fig (Ficus carica L.) cultivars in Morocco. In this study, 96 local and 44 introduced fig cultivars were assessed using 41 descriptors. The studied genotypes exhibited a highly significant variability based on morphological, colorimetric and physicochemical traits. Most of characters showed a high coefficient of variations (> 30%) revealing a high level of phenotypic diversity among the genotypes. Principal component analysis showed that the first 10 components explained 60.26% of the total inertia. Fruit weight, caliber, stalk, neck size, fruit shape, and skin color coordinates contributed to most of the total variation. Matrix of correlations showed significant positive and negative correlations among variables particularly fruit sizes, shape and skin color. Cluster analysis using the Unweighted Pair Group Method with Arithmetic Averages procedure for studied accessions revealed two major clusters and five subclusters. Principal component analysis scatter plot expressed a low level of variance compared to the cluster. It confirmed the same classification of the fig accessions, where fruit dimensions and skin color coordinates were the most discriminant descriptors. The results highlight a high phenotypic diversity within studied fig germplasm, which is probably more genetically related. The accessions panel can be recognized as an important gene pool for future breeding programs. The present study is of importance for planning fig genetic resources inventory, preserving the existing genetic variability and establishing national collections.