Fusarium proliferatum was isolated for the first time from roots and leaves of declining date-palm trees (Phoenix dactylifera L.) in the Al-Qassim and Al Medina Al Monawara regions in Saudi Arabia. The disease symptoms caused by F. proliferatum, which include wilt and dieback, were similar to those caused by F. oxysporum f. sp. albedinis, the causal agent of Bayoud, the most important disease of date palm found in North Africa. Koch's postulates were completed by stem injection of date-palm seedlings using two strains of F. proliferatum. The pathogenicity tests, performed on local cv. Succary using two strains of F. proliferatum isolated from roots, produced severe symptoms of disease. The identity of F. proliferatum was confirmed by comparing the data obtained by partial sequences of a large subunit of rDNA to American and European Gene Bank data. All nine F. proliferatum strains isolated from diseased plants were shown to belong to mating population D of Gibberella fujikuroi. Finally, the strains were also tested for the production of beauvericin, fumonisin B1, fusaproliferin, fusaric acid, and moniliformin. Two strains out of nine were able to produce all five toxins and all strains produced at least three of them. This is the first time that toxigenic F. proliferatum strains known to belong to mating population D of G. fujikuroi were isolated from diseased date-palm plants.

The efficacy of eight plant extracts (garlic, clove, garden quinine, Brazilian pepper, anthi mandhaari, black cumin, white cedar and neem) in controlling leaf rust disease of wheat was investigated in vitro and in vivo. In vitro, all treatments inhibited spore germination by more than 93%. Neem extract recorded 98.99% inhibition of spore germination with no significant difference from the fungicide Sumi-8 (100%). Under greenhouse conditions, seed soaking application in neem extract (at concentration of 2 ml/L) resulted in 36.82% reduction in the number of pustules/leaf compared with the untreated control. Foliar spraying of plant extracts on wheat seedlings decreased the number of pustules/leaf. Foliar spraying of plant extracts four days after inoculation led to the highest resistance response of wheat plants against leaf rust pathogen. Spray application of wheat seedlings with neem, clove and garden quinine extracts, four days after inoculation with leaf rust pathogen completely prevented rust development (100% disease control) and was comparable with the fungicide Sumi-8. Foliar spray application of wheat plants at mature stage with all plant extracts has significantly reduced the leaf rust infection (average coefficient of infection, ACI) compared with the untreated control and neem was the most effective treatment. This was reflected on grain yield components, whereas the 1000-kernel weight and the test weight were improved whether under one-or two-spray applications, with two-spray application being more effective in this regard. Thus, it could be concluded that plant extracts may be useful to control leaf rust disease in Egypt as a safe alternative option to chemical fungicides.

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Surveyed strawberry fields at three different districts (Abo Swar, EL-Kassasin and El-Manayef) in Ismailia Governorate during 2014-2016 growing seasons showed that 13 fungal species belonging to 13 genera were isolated from infected roots, runners and crowns segments of strawberry plants. The most frequent isolated fungi were; Macrophomina phaseolina (53.33%) and Colletotrichum acutatum (33.33%). These two pathogenic fungi were used in this study. Biological and chemical control experiments were conducted and significant differences in diseases incidence (DI%) and disease severity (DS%) were found among treatments of bioagents and chemical fungicides compared with control treatments. DI and DS percentages reached 0% when Bacillus subtilis or Rizolex were applied in plots of artificial infested soil with M. phaseolina and C. acutatum. Trichoderma harzianum occupied the second rank after B. subtilis, Rizolex (15 and 7.4% for DI) for M. phaseolina , (10 and 6.5% for DS)for C. acutatum, T. viride (16 and 16% for DI), (26 and 11% for DS) and Streptomyces canescens (20 and 21% for DI), (25 and 26% for DS), respectively. Moreover; Rizolex gave best results in pathogens control more than Topsin-M fungicide. In field experiment; the effect of soil disinfection using three treatments; two fumigants (Methyl bromide and Agrocelhone) and solar heating solarization applied on two strawberry cultivars (Festival and N-70) during 2015 and 2016 seasons were studied. Soil fumigation with Agrocelhone™ compound and Methyl bromide (MB) led to the best results for soil disinfection on both Festival and N70 Strawberry cultivars during two seasons. Percentage DI and DS of crown and root rot diseases occurred were (9.4, 9.0%) and (8.4, 7.5%) for both cultivars, respectively in 2015 it was very low (2.9, 3.0%) and (2.5 and 3.0%); respectively when applied again in 2016.

A new bacterial disease of date palm ‘sudden decline’ was found in the Al-Qassim region, Saudi Arabia. It is characterized by a sudden loss of vigor in the affected trees with the appearance of some blighted inner leaves. Symptoms develop rapidly and the whole tree assumes a straw color in about 2 weeks. The bud union is killed, and massive amounts of slime in a gel-like matrix could be detected in the heart of the affected tree. Biological and physiological tests of the isolated bacterium suggested that it belongs to the species Erwinia chrysanthemi. Artificial inoculation of various date palm cultivars using the technique of infusion under reduced pressure demonstrated that E. chrysanthemi was the causal agent and that cv. Succary was the most susceptible cultivar, whereas cvs. Roshody and Helwa were resistant to infection with E. chrysanthemi.

Imported tomato seed lots of different cultivars were assayed for the presence of seedborne bacterial pathogens. The liquid assay method was used for detection of the bacteria, and seed extracts were plated on different semi-selective media. Pseudomonas corrugata and Xanthomonas campestris pv. vesicatoria were detected in 14.7% and 12% of the seed samples tested respectively. These pathogens were identified by means of biochemical, physiological and pathogenicity tests as well as the Biolog GN Microplate System for X. campestris pv. vesicatoria. Both P. corrugata and X. campestris pv. vesicatoria were more easily identified on Tween B and CKTM media than on other media. This is the first report of the occurrence of these important pathogens on tomato seeds in Egypt.

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