# Protection of Oats against _Puccinia_ and _Drechslera_ Fungi in Various Meteorological Conditions
## 2 Materials and Methods  
This research was carried out in the years 2012-2016 based on the experiment established at the Field Experimental Station (PSD) Winna Gora, belonging to the Institute of Plant Protection-National Research Institute in Poznan. The studies were designed as two-factor experiments, in a randomized block design, with four field replications. The size of the experimental plots was 15 m\({}^{2}\) (1.5 m \(\times\) 10 m). The research was carried out on sandy clay soil, quality class III b, with a pH of 5.5. The subject of the studies were four husked oat varieties, i.e., Arab (Poznanska Hodowla Roslin Ltd., Tulce, Poland), Bingo (Hodowla Roslin Strzelce, Sp. z o.o., Strzelce, Poland), Arden and Breton (DANKO Hodowla Roslin Sp. z o.o., Choryni, Poland), and Maczo, a naked variety of Hodowla Roslin Strzelce, Sp. z o.o. The Arden variety is characterized by good resistance to helmitosporiosis, high resistance to powdery mildew, septoria leaf blight and crown and stem rust. The Arab variety has quite a high resistance to oat crown rust, average to stem rust, and low to the powdery mildew of cereals and grasses. The Bingo variety has a high resistance to powdery mildew, stem and crown rust, and leaf septoria, and it has quite high resistance to helmitosporiosis. The Breton variety has high resistance to powdery mildew, as well as good resistance to leaf septoria and helmitosporiosis, and the Maczo variety has high resistance to crown rust for oats and powdery mildew for cereals and grasses, but quite low resistance to helmitosporiosis for oats. In the following years, oats were sown with a Unia row seeder (Grudziadz, Poland) in rows with a spacing of 12.5 cm to a depth of 3.5 cm at a density of 550 grains \(\times\) m\({}^{-2}\), and they were harvested with an experimental plot combine harvester, the Wintersteiger Classic (Ried im Innkreis, Austria), at the full maturity stage (BBCH 89). After harvest, the grain yield (dt \(\times\) ha\({}^{-1}\)) at 14% humidity and the weight of 1000 grains were determined. In the conducted studies, fungicides containing active substances from the chemical group of strobilurins (azoxystrobin and picoxystrobin) and triazoles (epoxiconazole and tebuconazole) were used. Azoxystrobin was used at a dose of 250 g \(\times\) ha\({}^{-1}\) (Amistar 250 SC, 1.0 1 \(\times\) ha\({}^{-1}\), Syngenta Poland, Warsaw, Poland), picoxystrobin at a dose of 250 g \(\times\) ha\({}^{-1}\) (Acanto 250 SC, 1.0 1 \(\times\) ha\({}^{-1}\), DuPont Poland, Warsaw, Poland), epoxiconazole at 125 g \(\times\) ha\({}^{-1}\) (Rubric 125 SC, 1.0 1 \(\times\) ha\({}^{-1}\), Cheminova A/S, Harboere, Denmark), and tebuconazole at 250 g \(-\) ha\({}^{-1}\) (Sparta 250 EW, 1.0 1 \(\times\) ha\({}^{-1}\), Cheminova A/S, Lemvig, Denmark). The spraying treatments that were the subject of the research were carried out in the BBCH out stage of 59-63, using a [PERSON] backpack sprayer (Poznan, Poland) equipped with a compressed air cylinder and a spray boom with 4 nozzles (DG Teejet 110-02 VS, Teejet, Glendale Heights, IL, USA), which were placed at a distance of 25 cm from each other. The spray's liquid flow rate was set to 200 1 \(\times\) ha\({}^{-1}\), and the working pressure was 2.5 bars. The distance between the spray boom and the plant surface was 50 cm. The assessment of oat leaf infection with pathogenic fungi was carried out in BBCH stages 71-75, 10-14 days after treatment, on subflag and flag leaves marked as F and F1. The occurrence of _P. coronata_ and _D. avenue_ was assessed on the leaves. The determination of plant infection with leaf pathogens was performed according to the EPPO 2012 (European and Mediterranean Plant Protection Organization) disease determination key, in which it is expressed as a percentage of the infected leaf area with visible etiological symptoms, in accordance with the EPPO PP 1/26 methodology (4). For each disease, the percentage of plants with symptoms, regardless of their severity, and the infection index were calculated.