Investigating hyperparasites as potential biological control agents of rust pathogens on cereal crops

• Published in: Australasian plant pathology 2020-05, Vol.49 (3), p.231-238
• Main Authors: Wilson, A., Cuddy, W. S., Park, R. F., Harm, G. F. S., Priest, M. J., Bailey, J., Moffitt, M. C.
• Format: Article
• Language: English
• Subjects: Agricultural practices; Agriculture; Agronomy; Antagonism; Antagonists; Antibiosis; Biological control; Biomedical and Life Sciences; Cereal crops; Conidia; Control methods; Crop damage; Crops; Cultivars; Ecology; Entomology; Fungi; Fungicides; Germination; Host plants; Leaves; Life Sciences; Original Paper; Parasitism; Pathogens; Plant Pathology; Plant resistance; Plant Sciences; Rust fungi; Spore germination
• ISSN: 0815-3191; 1448-6032
• DOI: 10.1007/s13313-020-00695-8

Rust pathogens cause damage to cereal crops around the world, leading to reduced yield and profit. Current methods of rust control include fungicides, resistant cultivars, and preventative agronomic practices. Some hyperparasites are antagonists of plant pathogens and may provide a potential method of biocontrol against increasingly virulent strains of rust. Very little is known about the mechanism of inhibition of rust growth by hyperparasites, however, isolation of new strains and subsequent characterisation may reveal new treatment strategies for the control of rust. Here we report the isolation of six new fungal hyperparasites and their effects on the development of three Puccinia rust pathogens were examined in vitro , to determine the potential of each as biocontrol agents of rust. Cut-leaf sections of rust-susceptible wheat, barley and oat cultivars were treated with fungal hyperparasite conidia prior to infection with the rust species; Puccinia triticina, P. hordei, and P. coronata f. sp. avenae , respectively. Inhibition of rust spore germination tests were also performed on water agar plates co-inoculated with the isolates. In leaf sections, rust pustule number was significantly ( P