Potential for Biological Control of Botrytis cinerea in Pinus sylvestris Seedlings

Abstract

Grey mould (Botrytis cinerea Pers.: Fr.) is the most common economically important fungal disease in Swedish forest nurseries. In tests in a growth room, foliage of predisposed (preinoculation incubation at 35°C for 4 days) Scots pine (Pinus sylvestris L.) seedlings was sprayed with suspensions containing Mycostop®, Binab® TF.WP or GlioMix® at concentrations of 0.5, 1 or 0.5 g l⁻¹, respectively, and/or conidia of B. cinerea (10⁶ spores ml⁻¹). Binab and GlioMix reduced grey mould in needles by 94 and 92%, respectively, and were as effective as the fungicide Euparen® M 50 WG, while Mycostop reduced disease by 51%. In one trial in a forest nursery, Mycostop, Binab and GlioMix, each applied two and four times during the growing season, suppressed spontaneous B. cinerea infections in needles of first year container-grown P. sylvestris seedlings by 16–57%, and were as effective as recommended fungicidal sprays. It was concluded that biological control has potential to effectively suppress grey mould in seedlings in forest nurseries.

Keywords:

• Biocontrol
• conifer seedlings
• Gliocladium
• Streptomyces griseoviridis strain K61
• Trichoderma harzianum
• Trichoderma polysporum

Acknowledgments

This work was financially supported by MISTRA (Swedish Foundation for Environmental Strategic Research). We thank the forest nurseries Nässja (Korsnäs AB) and Lugnet (Sveaskog AB) for their co-operation with the field experiments. We acknowledge the companies Ticab AB and BINAB Bio-Innovation AB for providing the biocontrol agents. We are also grateful to Emma Carlén and Anna Andréasson for help with the estimation of grey mould incidence.