Morpho-geometric identification of leaflets from male, female and hermaphrodite populations of the carob tree (Ceratonia siliqua L.) in Algeria

Résumé fourni par la source

The carob tree is an agro-salvo-pastoral species that has an important socio-economic and ecological role. For many years, the horticultural in Algeria has been in regression, mainly due to the effect of anthropic factors. This regression has led to the increase in carob tree prices, which makes this speculation gainful for farmers and agro-industrialists. However, the problem of sexual determinism in carob remains an important difficulty for the creation of orchards and the development of genetic improvement programs for the species. So the object of this study is to identify and distinguish by a morpho-geometric characterization of the leaflets, the carob trees of male, female and hermaphrodite sex, from 21 different regions of the Algerian north with 781 leaflets characterized through the selection of 16 landmarks. Once recorded in digital format (TPS), the morpho-geometric conformations are aligned and superimposed using the Procrustean superposition technique. Analysis of variance (ANOVA) of the data revealed highly significant differences in shape (p=0.0001), and significant centroid size (p=0.0243) between the three populations studied. Descriptive analysis of size showed only one significant difference (p=0.035) between the size of hermaphrodite and male leaflets. Principal component analysis (PCA) showed inertia of 57.15% between the first two components and revealed three different shapes. The analysis of canonical variants (CA) distinguished these different forms, the female leaflet so much towards an elliptical form with a base contracted in node downwards and with apex characterized by a closed angle. While the shape of the male leaflet is generally oval with a scattered base and with apex characterized by an open angle. The leaflets of hermaphrodites resemble the leaflets of males (oval) but with a flattened base. These results can be used as a means to make a preliminary selection of young carob plants.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.