Vertical distribution of foliar pathogens on wheat

R. Rodeva1*, Z. Stoyanova1, S. Nedyalkova2, M. Pastirčák3, M. Hudcovicova3

1Department of Applied Genetics and Plant Biotechnology, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 21 Acad. G. Bonchev, 1113 Sofia, Bulgaria
2Field Crop Institute, 6200 Chirpan, Bulgaria
3Plant Production Research Center Piestany, 122 Bratislavska, 92168 Piestany, Slovakia

Abstract. Wheat (bread and durum) is the most widely distributed crop in Bulgaria. Leaf spotting diseases of wheat are associated mainly with a complex of three fungal pathogens, which cause septoria leaf blotch. Lately, Pyrenophora tritici-repentis has been increasingly observed in Bulgaria. The purpose of the present investigation was to estimate the vertical distribution of these important leaf spotting pathogens during the post-anthesis period making a comparison between bread and durum wheat cultivars. P. tritici-repentis was the ubiquitous fungus in all studied sites with higher frequency of occurrence from lower to upper leaf layers. The inciters of septoria leaf blotch were predominant on bread wheat especially on cultivar Enola due to its susceptibility to Zymoseptoria tritici. In the lower and middle leaf layers they were more frequent than P. tritici-repentis. On durum wheat P. tritici-repentis was the most prevalent pathogen in all leaf layers especially on cultivar Saturn, while Z. tritici was found in 6 samples only in 2013. Stagonospora avenae f.sp. triticea was established on T. aestivum and T. durum cultivars with slightly prevalence on durum wheat. S. nodorum was recorded very seldom (on bread wheat) or missing at all (on durum wheat).