Biological Control of Fusarium Seedling Blight Disease of Wheat and Barley

Abstract

Fusarium fungi, including F. culmorum, cause seedling blight, foot rot, and head blight diseases of cereals, resulting in yield loss. In a screen for potential disease control organisms and agents, Pseudomonas fluorescens strains MKB 100 and MKB 249, P. frederiksbergensis strain 202, Pseudomonas sp. strain MKB 158, and chitosan all significantly reduced the extent of both wheat coleoptile growth retardation and wheat and barley seedling blight caused by F. culmorum (by 53 to 91%). Trichodiene synthase is a Fusarium enzyme necessary for trichothecene mycotoxin biosynthesis; expression of the gene encoding this enzyme in wheat was 33% lower in stem base tissue coinoculated with Pseudomonas sp. strain MKB 158 and F. culmorum than in wheat treated with bacterial culture medium and F. culmorum. When wheat and barley were grown in soil amended with either chitosan, P. fluorescens strain MKB 249, Pseudomonas sp. strain MKB 158, or culture filtrates of these bacteria, the level of disease symptoms on F. culmorum-inoculated stem base tissue (at 12 days post- F. culmorum inoculation) was >/=31% less than the level on F. culmorum-inoculated plants grown in culture medium-amended soil. It seems likely that at least part of the biocontrol activity of these bacteria and chitosan may be due to the induction of systemic disease resistance in host plants. Also, in coinoculation studies, Pseudomonas sp. strain MKB 158 induced the expression of a wheat class III plant peroxidase gene (a pathogenesis-related gene).

The variability of the occurrence of Fusarium culmorum in winter wheat grain in relation to climatic conditions and cultivation methods

“…Under laboratory conditions, the addition of two microbiological strains P. fluorescens MKB 100 and Pseudomonas spp. MKB 158 and 249, helped in containing head blight in seedlings caused by F. culmorum (Khan et al, 2006). In the cases of wheatwheat rotation, phytosanitary mechanism is triggered off by all kinds of catch crops, especially fodder plants such as oilseed rape, white mustard and oilseed radish.…”

Antifungal activities of an endophytic Pseudomonas fluorescens strain Pf1TZ harbouring genes from pyoluteorin and phenazine clusters

“…Here we describe the isolation and characterization of Pseudomonas fluorescens Pf1TZ harbouring antifungal activity against a variety of phytopathogenic fungi. To investigate this activity, we selected a number of fungi that are known to cause serious diseases on many different plants, namely, A. niger, A. alternaria and B. cinerea in addition to F. culmorum, F. graminearum and F. oxysporum which were reported to be relatively resistant to chemical and biological pesticides (Khan et al 2006). Fungicides of Pf1TZ were separated by flash chromatography and three active fractions were retained, namely, Pf1TZ-17, Pf1TZ-23 and Pf1TZ-41.…”

Plant Growth Promoting Rhizobacteria: Mechanism and Current Prospective

“…Besides the direct effect, PGPR affect the plant by controlling pathogens which are mostly involved in competition and production of metabolites that affect the pathogen directly by siderophores production, lytic enzymes and antibiotics production and by induced Pseudomonas chlororaphis Sorghum Macrophomina phaseolina [85] Pseudomonas fluorescens Tobacco Tobacco necrosisvirus [86] Pseudomonas fluorescens MKB 100 and MKB 249, Wheat and barley Fusarium culmorum [87] Pseudomonas aeruginosa Mung bean Root rot [88] Enterobacter sp. Chickpea Fusarium avenaceum [89] Azospirillum brasilense Prunus cerasifera L.…”