The present study demonstrates a procedure for the rapid development of a high number of somatic embryos from embryogenic suspension culture. This method might be efficient for mass propagation of Phoenix dactylifera L. Embryogenic callus placed in liquid medium with 10 )5 M ABA yielded an average 72 embryos per 100 ml of culture medium within 2 months, while those placed on solid medium yielded an average of 33, 20 and 16 embryos per 100 ml of culture medium respectively for 10 )7 , 10 )6 and 10 )5 M ABA after 4 months. The combination of 2,4-DI D Ichlorophenoxyacetic acid (2,4-D D ) (4.5 · 10 )7 M), glutamine (6.7 · 10 )4 M), and ABA (10 )5 M) (L8 liquid medium) showed a beneficial effect on somatic embryos production compared to 2,4-D D and glutamine alone, while this combination significantly ( p < 0.05) increased the accumulation of storage proteins (144 and 138 mg g )1 DW respectively for Jihel and Bousthami noir cultivars) in somatic embryos. The somatic embryos which underwent maturation on medium containing only 4.5 · 10 )7 M 2,4-D D and 10 )5 M ABA (L6 liquid medium) accumulated more sugars (292 and 265 mg g )1 DW respectively for Jihel and Bousthami noir) than those matured on any other liquid medium. Histological studies revealed that somatic embryos (developed in L6 and L8 liquid media) accumulated less reserve compounds (proteins and sugars) than zygotic embryos. The addition of activated charcoal (0.25 and 0.5 g l )1 ) and phytagel Ò (2.5 g l )1 ) to the germination medium may be useful for enhancing the germination of Phoenix dactylifera somatic embryos.Abbreviations: ABA -abscisic acid; BAP -benzylamino-purine; BSTN -bousthami noir cultivar; 2,4-D D -2,4-dichlorophenoxyacetic acid; Glu -glutamine; JHL -Jihel cultivar; MS -Murashige and Skoog (1962) medium; FW -fresh weight; PAS -periodic acid-shiff; NBB -naphthol black blue

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A non-constitutive phenolic compound was isolated from date palm (Phoenix dactvlifera L.

Phenolamides in the Rachis of Palms: Components of the Defence Reaction of the Date‐palm towards Fusarium oxysporum f.sp. albedinis, the Causal agent of ‘Bayoud’ This is the first study showing evidence of the production of phenolic and phenolamidic compounds in date palm tissues in response to attack by Fusarium oxysporum f.sp. albedinis (Foa), the causal agent of the wilt called bayoud. Marked quantitative and qualitative differences were recorded in the production of such compounds when infected and healthy rachis, were compared. In addition, localized accumulation of some compounds was detected when infected and healthy parts of the same rachis were analysed. Three induced hydroxycinnamoylamides were detected in high concentrations. They were isolated and tested for their toxicity against Foa. These compounds were shown to strongly inhibit conidial germination and germ tube growth of the pathogen and must be considered as phytoalexins. The role of amides in the date palm resistance to the bayoud is discussed.