Control of Stagonospora nodorum and Septoria tritici in wheat by pre-treatment with Drechslera teres, a non-host pathogen

A field study is described which explored the possibility of controlling St agonospora nodorum and Septoria tritici on wheat using a barley pathogen, D rechslera teres. Pre-treatment of wheat cv. Hussar flag leaves with D. tere s resulted in a significant reduction in disease caused by S. nodorum and S . tritici, resulting in a significant increase in grain yield. When cv. Bri gadier leaves were treated with D. teres prior to inoculation with S. nodor um there was an initial increase in disease expression whilst D. teres had no effect on symptoms produced by S. tritici on cv. Brigadier. There was si gnificantly less disease on leaves of cvs. Hussar and Brigadier pre-treated with D. teres prior to inoculation with an equal mixture of S. nodorum and S. tritici compared to plants pre-treated with water. It is concluded that D. teres and other non-host pathogens show potential as biological control agents for S. nodorum and S. tritici.