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Field trials in two sowing dates were conducted to assess the possibility of applying bioagents as wheat grain dressing for suppressing severity of foliage diseases, i.e. powdery mildew, septoria leaf blotch and stem rust under field conditions. Bioagents, such as Bacillus subtilis, Azospirillum brasilense, Pseudomonas fluorescens, Trichoderma harzianum and Plant Guard as well as the fungicide Topsin M70, were evaluated. All treatments reduced diseases severity compared with control. Generally, Giza 171 cv. represented the lowest diseases severity followed by Misr 1 and Gemmiza 12. Moreover, early sown cultivars (10th November) showed lower disease severity than those sown late (10th December). Wheat grains treated with B. subtilis and T. harzianum revealed the highest effect on all diseases severity followed by the other applied treatments. Overall, such applied treatments have the possibility to suppress wheat foliar diseases as a safe alternative to chemical fungicides and avoid harmful effect for human health and polluting the environment. [ABSTRACT FROM AUTHOR]

Zea maysL. ssp.mexicana(teosinte) is a naturally occurring grass related to maize. The two plants have developed foliar fungal diseases that can be controlled with beneficial bacterial antagonists. While the beneficial effects on stem and root development of the application of bacteria of the genusAzospirillumis widely known, the effects of the bacteria on the control of the phytopathogenic fungi associated with teosinte leaves and seeds are unknown. Bacterium of the speciesA. brasilensethat present acetylene reducing activity, siderophore production and the ability to antagonise pathogenic fungiin vitroandin vivoin teosinte plants were selected for this study, in which the incidence of fungal diseases caused byAlternaria, BipolarisandFusariumwere reduced in plants. Furthermore, biomass (root and stem) production increased, improving teosinte plant health in greenhouse and field conditions. [ABSTRACT FROM PUBLISHER]

A modified approach was adopted to develop co-flocs consisting of Azospirillum brasilense MTCC-125 and Pseudomonas fluorescens MTCC-4828. The results of our study revealed that both Azospirillum and Pseudomonas strains exhibited a higher survivability when embedded in the flocs. The survivability of the strains in co-floc was found to be higher when compared to the log phase vegetative cells in different inoculant carriers, spermosphere rhizoplane and rhizosphere. The co-floc treatment has also significantly increased the germination percentage and vigour index of rice. In the present study flocculation was found to play a major role in enhancing adhesion of both the strains to rice roots. The co-flocs were studied for their efficiency to induce resistance in rice crop against rice blast. The relative role of Azospirillum and Pseudomonas co-flocs in the induction of resistance against the phytopathogen was evaluated. It was found that when the activities of polyphenol oxidase, peroxidase and phenol were high and when the relative amounts of the sugars were low, the disease infestation was less and vice versa. The association of these compounds strongly implies their role as casual agents of induced resistance against Pyricularia oryzae. [ABSTRACT FROM AUTHOR]

An investigation was conducted to study the effect of biofertilisers (Glomus fasciculatum, Azospirillum brasilense, Azotobacter chroococcum and Micro Phos) and pesticides (carbofuran and bavistin) on the management of root-rot and root-knot disease complex of balsam. The individual application of biofertilisers (G. fasciculatum, A. brasilense and A. chroococcum) significantly improved the plant growth parameters viz., length, dry weight and number of flowers compared to untreated-uninoculated plants. The simultaneous inoculation of plant with Meloidogyne javanica and Macrophomina phaseolina in the pots treated with either of the biofertilisers (G. fasciculatum, A. brasilense and A. chroococcum) and pesticides (carbofuran/bavistin) significantly improved the plant growth parameters and reduced the reproduction factor, number of galls and intensity of root-rot compared to untreated-inoculated plants. On the other hand, the plants treated with Micro Phos neither significantly improved the plant growth parameters nor reduced the reproduction factor, number of galls and intensity of root-rot. Among the biofertilisers and pesticides, carbofuran was found to be the most effective in the management of disease complex of balsam followed by bavistin, G. fasciculatum, A. brasilense and A. chroococcum. [ABSTRACT FROM AUTHOR]