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A total of 250 endophytic fungal isolates, representing 30 morphotaxa, were isolated and characterised, they were collected from the different living symptomless parts of date palm trees of orchards of six Egyptian governorates. Colonisation was greater in samples from the midrib than in those from laminar tissue and slightly greater at the tip of the lamina compared with the base of the leaf. Acremonium spp. were frequently isolated as date palm root endophytes. Acremonium isolates were screened in Petri dishes to select the highest antagonistic one against an Algerian isolate of Fusarium oxysporum f.sp. albedinis. Two-week-old axenically reared date palm seedlings grown in Petri dishes were directly injected with spore suspension (1.5 Â 10 7 spores/ml) of a pure culture of the virulent antagonistic isolate of Acremonium sp. One week after endophytic colonisation, date palm seedlings were then challenged with the pathogen, Fusarium albedinis. The challenged seedlings exhibited a significant reduction in wilt symptom percentage (by 87.0%), while the seedlings exposed to Fusarial toxin without pathogen exhibited the wilt disease symptoms. This indicates that the endophyte ably depresses any toxic action of F. albedinis. The endophytic fungus was recovered from sites distant from the point of inoculation after six months from the application, indicating that the Acremonium sp. has the potential to move throughout the tissue plant, even the end time of trial. The Acremonium mode of action, as a biocontrol agent, was discussed.

Eight lectins, four of which were used in pure forms, i.e. lectins of white bean seeds, red bean (Adzuki) seeds, pea seeds and lentil seeds. The other four were used in crude forms for the first time, i.e. lectins of white bean seeds, soybean seeds, moringa seeds and orchid tree seeds. All plant lectins tested in vitro against the growth of three fungi that cause strawberry fruit-rot, i.e. Botrytis cinerea, Corynespora cassiicola and Alternaria alternata. The crude lectin exhibited high ability to inhibit radial growth of these fungi compared with the pure lectin, this may be due to the presence of other effective compounds besides lectins in the extract. There was congruence in the general effect of both tested crude and pure lectins on fungal growth, where Botrytis growth was the most affected by any used lectin. Moringa crude lectin was high efficient in inhibiting the radial growths with 80.00%, 71.33% and 53.00%, respectively. Postharvest spraying of strawberry fruits with crude lectins succeeded in reducing soft-rot severity compared to control under laboratory conditions outside refrigerators. Fungal treating in vitro with crude lectins was consistent with postharvest fruit treating, where moringa crude lectin showed high soft-rot inhibition efficiency (70.40, 66.28 and 30.93%). The results indicated possibility of exploiting crude plant lectins to discourage postharvest fruit-rot and it is tempting to repeat the experiment on plants in the greenhouse and then in the field if the necessary quantities of lectins are available when lectin production gene is transferred to a fast-developing microorganism.

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