The Menara gardens in Marrakech (Morocco), established in the 12th century, comprise more than 2000 olive trees. To assess the genetic diversity within these gardens, we performed SSR analysis of 128 randomly sampled olive trees. Using 15 SSR loci which revealed 70 alleles, we identified 16 distinct genotypes. The analysis of chloroplast DNA polymorphism allowed to identify 2 chlorotypes: COM1 for 2 genotypes and CE1 for all others. Among the 128 trees analysed, Picholine marocaine was the prevalent cultivar represented by 100 trees (78%), the 28 remaining trees being classified into 15 distinct genotypes. However, four genotypes were closely related to Picholine marocaine from which they probably derived through somatic mutations. The genotypic and genetic diversity observed in Menara gardens compared with the genotype diversity from different areas (North and Atlas); these facts support the hypothesis that these gardens have been planted with trees probably originating from different areas of Morocco. Our results point out an important concept for ex situ conservation: the assumption that local Moroccan olive germplasm was empirically, but not purposively, conserved already in Menara gardens.

The inoculation of the seedling roots of the resistant (Bousthami Noir) and susceptible (Jihel) date palm (Phoenix dactylifera) cultivars by Fusarium oxysporum f. sp. albedinis induced an increase in phenylalanine ammonia-lyase (PAL) activity. The response of the PAL activity in the resistant cultivar was faster and higher than in the susceptible one. However, the elicitation of the seedlings with the hyphal wall elicitor (HWE) of the pathogen induced identical PAL activity in both cultivars. In the resistant cultivar, the the PAL activity elicited with the HWE was not influenced by the addition of the fungal culture filtrate (FCF) whereas it was suppressed in the susceptible cultivar. This FCF suppressor effect was dose-dependent, not influenced by sodium periodate, whereas it was strongly reduced by the heat (121 °C for 45 min) and pronase E. These results show that differential induction of the defence mechanisms in both cultivars was not related to differences in the induction of the PAL activity, but to the suppression of its elicitation in the susceptible cultivar.

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In order to verify the reliability of hybrid population issued from crossing between 3 clones of "Picholine marocaine" cultivar and the "Picholine du Languedoc" cultivar, the descendants and their parents were analysed using 35 microsatellite loci. No offspring resulted from self crossing of "Picholine marocaine" cultivar and 218 descendants among 220 analysed are legitimate. This study showed clearly a segregating population and may be used as a genetic material for linkage map construction and for phenotyping resistance traits related to Spilocaea oleagina disease.