Control of infection and sporulation ofBotrytis cinerea on bean and tomato by saprophytic bacteria and fungi

Abstract

Sixty isolates of saprophytic microorganisms were screened for their ability to reduce the severity of grey mould (Botrytis cinerea) infection and sporulation. Isolates of the bacteria Xanthomonas maltophilia, Bacillus pumilus, Lactobacillus sp., and Pseudomonas sp. and the fungus Gliocladium catenulatum reduced germination of conidia of the pathogen and controlled disease on bean and tomato plants. Their activity under growth room conditions was good, consistent, and similar to the activity of the known biocontrol agent, Trichoderma harzianum T39 (non-formulated). Although the tested isolates may for nutrients with the germinating conidia of B. cinerea, resistance induced in the host by live or dead cells were also found to be involved. Inhibitory compounds were not detected on treated leaves. Sporulation of B. cinerea after its establishment on leaves was also reduced by the above mentioned isolates and by Penicillium sp., Arthrinium montagnei, At. phaeospermum, Sesquicillium candelabrum, Chaetomium globosum, Alternaria alternata, Ulocladium atrum, and T. viride. These sporulation-inhibiting fungi did not reduce the infection of leaves by B. cinerea. Most of these selected fungi and bacteria were capable of reducing lesion expansion.

Suppression ofBotrytis cinereasporulation on irradiated grape leaf tissue by the antagonistic bacteriumSerratia liquefaciens

“…Our results showed that time of application of antagonist in relation to B. cinerea influenced the results such that best control was achieved when the antagonist was allowed to establish before pathogen colonisation. Similar results were reported by Elad et al (1994) and Peng & Sutton (1991), This could be the result of a number of reasons, for example, the antagonist may have a minimum time requirement to start producing inhibitory compounds, or be a poor competitor for resources such as space and nutrients or only exert an inhibitory effect on germinating conidia. The conflicting results observed for the 21-day assessment were believed to be because of a problem with some leaf discs drying out.…”

Long-term effect of mineral fertilizers and amendments on microbial dynamics in an alfisol of Western Himalayas

“…Mucor and Penicillum were also observed in some of the treatments. The presence of Gliocladium, a bio-control agent against many soil borne pathogens 10 is an interesting observation which probably refl ects the acquisition of natural control mechanism against certain pathogens observed in the present experimental set up.…”

Chitinases from the Plant Disease Biocontrol Agent, Stenotrophomonas maltophilia C3

“…Biological control by these strains has been attributed to induced resistance (6), antibiotics (21), and protease (5). Chitinase production was expressed in most strains of S. maltophilia evaluated in vitro by O'Brien and Davis (22), but only 1 of 11 Verticillium-inhibitory strains tested by Berg et al (2) was chitinolytic, indicating that involvement of chitinase in fungal inhibition by S. maltophilia is strain specific.…”

“…Besides strain C3, a number of S. maltophilia strains inhibit fungal growth or infection when applied to plants (2,5,6,(10)(11)(12)21), but there is no mechanism of antagonism that is common among these strains. Biological control by these strains has been attributed to induced resistance (6), antibiotics (21), and protease (5).…”