M. M. Abdel-Kader

Integration between Compost, Trichoderma harzianum and Essential Oils for Controlling Peanut Crown Rot under Field Conditions

The effect of T. harzianum and some essential oils alone or in combination with compost on the peanut crown rot disease under field conditions was evaluated. Under laboratory conditions, results indicated that all concentrations of essential oils significantly reduced the growth of A. niger. Complete reduction was obtained with thyme and lemongrass oils at 0.5%. All T. harzianum isolates significantly reduced the growth of A. niger. The highest reduction was obtained with isolate no. 1 which reduced the growth by 81.1%. Under field conditions, results indicated that all treatments significantly reduced the peanut crown rot disease. The highest reduction was obtained with combined treatments (compost

Biological and Chemical Resistance Inducers Approaches for Controlling Foliar Diseases of Some Vegetables under Protected Cultivation System

Different alternative approaches of antagonistic bio-agents, Trichoderma harzianum, T. Viride, Bacillus subtilis, Pseudomonas flourescens and Saccharomyces cerevisiae and plant resistance inducers, Calcium chloride, Potassium monohydrogen phosphate, Potassium bicarbonate, Saccharin, Ascorbic acid, Chitosan and Humic & Folic acid (mixture) in addition to thyme oil were applied as plant spray to evaluate their efficacy against vegetables foliar diseases incidence was carried under open greenhouse conditions. The recorded foliar diseases, i.e. Powdery, Downy mildews of Cucumber, Cantaloupe and Pepper as well as Early, Late blights of Tomato were significantly reduced at all treatments either alone or in combinations comparing with untreated plants. Application with either T. harzianum or B. subtilis showed significant reduction in diseases incidence comparing with the other applied bio-agents. The other bio-agent treatments, T. viride, P. fluorescens and S. cerevisiae recorded moderate reduction in this concern. Under artificial infestation the most significant reduction in foliar diseases incidence and severity of tested vegetables were recorded in combined treatments of combined chemical inducers and S. cerevisiae, i.e. (Chitosan+Thyme oil); (Chitosan+Saccharin); (Chitosan+Calcium chloride+S. cerevisiae); (Chitosan+Potassium monohydrogen phosphate); (Saccharin+Potassium monohydrogen phosphate); (Humic & folic+Thyme oil) and (Chitosan+S. cerevisiae) comparing with other applied treatments as well as untreated control. The present review summarizes studies aimed to evaluate different control measures of fungicides alternatives approachs, e.g. some plant resistance inducers, essential oils and bio-control agents on the foliar diseases incidence of some vegetables under greenhouse and plastic house conditions. This work was carried out during a project supported by the Science and Technology Development Fund (STDF), Egypt.

First Report of Ashy stem blight caused by Macrophomina phaseolina on Aeonium canariense in Egypt

Cactus plants Aeonium canariense L. (Webb & Berthelot) showing symptoms of ashy stem blight disease, collected from some ornamental nurseries, resulted in isolation of the causal organism Macrophomina phaseolina (Tassi) Goid . The in vitro optimum temperature for fungal growth was recorded at 30 0 C. Topsin-M showed high inhibitory effect on the fungal growth in vitro. Complete growth inhibition of M. phaseolina was observed at concentration of 4ppm, while the growth of the bioagent Trichoderma harzianum inhibited completely at 10ppm. Antagonistic ability of T. harzianum against M. phaseolina increased gradually in the presence of the fungicide in growth medium to cause complete reduction in pathogenic fungal growth at 2ppm of Topsin-M. Under greenhouse conditions application of integrated treatment of T. harzianum and Topsin-M had superior effect for suppressing the disease incidence of cactus plants Aeonium canariense L . by 100% comparing with each individual treatment of either fungicide (86.67%) or the bioagent (73.33%). It could be suggested that application of biological and fungicidal integrated treatment might be used as successful control measure for ashy stem blight of cactus plants Aeonium canariense L . cactus plants Aeonium canariense L. To the best of our knowledge this is the first report for M. phaseolina caused infection to cactus A. canariense in Egypt.

Effect of Commercial Cyanobacteria Products on the Growth and Antagonistic Ability of Some Bioagents under Laboratory Conditions

Evaluation of the efficacy of blue-green algal compounds against the growth of either pathogenic or antagonistic microorganisms as well as their effect on the antagonistic ability of bioagents was studied under in vitro conditions. The present study was undertaken to explore the inhibitory effect of commercial algal compounds, Weed-Max and Oligo-Mix, against some soil-borne pathogens. In growth medium supplemented with these algal compounds, the linear growth of pathogenic fungi decreased by increasing tested concentrations of the two algal compounds. Complete reduction in pathogenic fungal growth was observed at 2% of both Weed-Max and Oligo-Mix. Gradual significant reduction in the pathogenic fungal growth was caused by the two bioagents and by increasing the concentrations of algal compounds Weed-Max and Oligo-Mix. The present work showed that commercial algal compounds, Weed-Max and Oligo-Mix, have potential for the suppression of soil-borne fungi and enhance the antagonistic ability of fungal, bacterial, and yeast bio-agents.

Bioagents and Commercial Algae Products as Integrated Biocide Treatments for Controlling Root Rot Diseases of Some Vegetables under Protected Cultivation System

Integrated commercial blue-green algae extracts and bioagents treatments against vegetables root rot incidence when used as soil drench under greenhouse and plastic house conditions were evaluated. All applied treatments reduced significantly root rot incidence at both pre- and postemergence growth stages of cucumber, cantaloupe, tomato, and pepper plants compared with untreated check control. In pot experiment, the obtained results showed that treatments of Trichoderma harzianum or Bacillus subtilis either alone or combined with commercial algae extracts were significantly superior for reducing root rot disease for two tested vegetable plants compared with the other tested treatments as well as control. It is also observed that rising concentrations of either algae products, Oligo-X or Weed-Max, were reflected in more disease reduction. Promising treatments for controlling root rot disease incidence were applied under plastic houses conditions. As for field trails carried out under plastic houses conditions at different locations, the obtained results revealed that the applied combined treatments significantly reduced root rot incidence compared with fungicide and check control treatments. At all locations it was observed that Weed-Max (2 g/L) + Bacillus subtilis significantly reduced disease incidence of grown vegetables compared with Oligo-X (2 mL/L) + Trichoderma harzianum treatments. An obvious yield increase in all treatments was significantly higher than in the control. Also, the harvested yield in applied combined treatments at all locations was significantly higher than that in the fungicide and control treatments.