The pectin polysaccharides from leaves of Argania spinosa (L.) Skeels, collected from Stidia area in the west coast of northern Algeria, were investigated by using sequential extractions and the resulting fractions were analysed for monosaccharide composition and chemical structure. Water-soluble pectic (ALS-WSP) and chelating-soluble pectic (ALS-CSP) fractions were obtained, de-esterified and fractionated by anion-exchange chromatography and characterized by sugar analysis combined with methylation analysis and 1H and 13C NMR spectroscopy. The data reveal the presence of altering homogalacturonan (HG) and rhamnogalacturonan I (RG-I) in both pectin fraction. The rhamnogalacturonan I (RG-I) are consisted of a disaccharide repeating unit [→ α-D-GalpA-1,2-α-L-Rhap-1,4 →] backbone, with side chains contained highly branched α-(1 → 5)-linked arabinan and short linear β-(1 → 4)-linked galactan, attached to O-4 of the rhamnosyl residues.

Ascochyta blight resistance was studied in half-diallel cross involving eight genotypes of chickpea at seedling and adult stages. The disease was rated in the greenhouse with a modified scale from 0 to 100%. The diallel analysis was performed on 28 F1 and their F2. The results were analyzed with the Hayman and Griffing methods. The general combining ability is most important for two generations, is highly significant for the two stages, and is more important than specific combining ability. This result reflects a strong preponderance of additive effects and epistasis additive × additive with respect to dominance effects in this material for the two generations, which shows the predominance of additive versus dominance. Estimates of heritability are very high. The additive effects have the highest value indicating the importance of this component for resistance toAscochyta. For seedling stage, the negative sign of F for both generations indicates that there are much more recessive alleles that affect resistance to the disease. In adult stage, F is positive in both generations and shows more dominant alleles that control plant reaction to pathogen. H2is positive in both generations which show that dominant genes are acting mostly towards the susceptibility.

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The chickpea (Cicer arietinum) is one of the leguminous species most appreciated by consumers in the Mediterranean basin, while being an important source of protein. Nevertheless, its crop yields are greatly limited by several biotic and abiotic stresses, the main one being Ascochyta rabiei, the causal agent of anthracnose. As traditional breeding methods have proved to be ineffective in controlling this pathogen, resorting to biotechnological methods is necessary. Therefore, in this study, the callogenic capacity of stem and leaflet explants from three genotypes of chickpea, namely ‘FLIP 84-92 C’, ‘ILC 32-97’, and ‘ILC 263’, cultured on Murashige and Skoog (MS) medium with different hormonal balances of auxins (indole-3-acetic acid [IAA] and 2,4-dichlorophenoxyacetic acid [2,4-D]) and cytokinin (kinetin), was determined. For all the genotypes, high percentages of callogenesis were recorded in the different explants grown on an MS medium with 2 mg of both IAA and kinetin. Then, a patho-system of Cicer arietinum calluses with Ascochyta rabiei was investigated, followed by a histological assessment of this interaction. The presence of the fruiting bodies of the pathogen was revealed in the calluses of the ‘ILC 32-97’ and ‘ILC 263’ genotypes. Notably, the latter showed a high sensitivity to the pathogen, as indicated by an abundance of pycnidia in its tissues. As for the ‘FLIP 84-92 C’ genotype, the histological sections showed a total absence of inter- and intracellular fruiting bodies of the pathogen in the callus tissues. Therefore, this genotype was considered as resistant to Ascochyta rabiei.