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The root-knot nematode, Meloidogyne incognita infecting the potato Solanum tuberosum L.cv. sponta could be controlled under field conditions in Egypt using some biocontrol compounds. These compounds were a suspension of spores of two species of antagonistic rhizobacteria Bacillus subtilis and Pseudomonas fluorescens (1:1) and the nematode trapping fungi Dactylaria brochopaga in a suspension or granule form. Each suspension was added to the soil at three rates 0.5, 1.0 and 2.0 liter/ karate (karate =175m2) before planting the tubers. D. brochopaga as granules was similarly added at the rates of 0.5, 1.0, and 2.0 kg/karate. Furadan was also used as a granular nematicide at 1 kg/karate in addition to an untreated check. The results showed that all treatments significantly reduced the population densities of M. incognita in soil, as well as gall formation on potato roots, compared to control at harvesting. Such nematicidal effect increased proportionally by successive increase of concentration. D. brochopaga as a granule form was the most effective treatment on both juvenile numbers in the soil recorded 59.82, 76.21 and 77.68% reduction and on root galls, recorded 48.56 and 68% reduction, at the three tested doses, respectively. The suspension containing D. brochopaga was less effective, it achieved 28.56% and 40% gall reductions but 28.57%, 68.75%, and 55.38% reductions in juveniles; respectively. Total numbers of pathogenic fungi were affected by the biocontrol agents added. Their numbers were negatively affected with all treatments compared to control. Also, the total number of B. subtilies and P. fluorescens were increased by time. Generally, potato yield was significantly increased due to treatments, especially when applied at high dosage levels. [ABSTRACT FROM AUTHOR]

A field trial was conducted at El-Shourouk Farm, El-Beheira governorate, Egypt to determine the effectiveness of the commercial bio-product Dbx 1003, 20% containing the nematode-trapping fungus, Dactylaria brochopaga against rootknot nematode, Meloidogyne incognita infesting grapevine variety Superior. Its effects on plant growth criteria and yield production were also investigated. The fungus was introduced to soil by either of two ways; soil was drenched with spore suspension at the rate of 3L/tree and ½ kg of a vermiculite substrate, as a carrier of spores and mycelia, was added around each tree, both as single and twice applications in autumn and spring. All treatments significantly (p ⩽ 0.05) reduced M. incognita 2nd instar juvenile in the soil and number of root galls compared to the untreated control. Significant yield increases were recorded at all treatments. Twice applications of spores' suspension gave highest yield production. [ABSTRACT FROM AUTHOR]