The implications of Panicum miliaceum in the viral epidemiology of cereals

Common millet (Panicum miliaceum L.) is a spreading weed in Hungary, it can be found mostly on maize fields, but it has been investigated, that it is more and more often occurring in other cultivated plants, like potato, wheat, and other cereals. It can widely spread because of the lack of seed dormancy. This weed is a close relative to wheat, so the aim of the experiment was to investigate, which wheat viruses can infect of the common millet (Panicum miliaceum L.). Forty-five millet leaf samples were collected from fields in 2014 and 2015 near Keszthely, Zala County, and 35 leaf samples in 2016 near Keszthely. After the collection, the samples were immediately frozen and stored at - 20○C. The DAS ELISA serological method was used to determine wheat viruses from the leaves. Among the 80 collected leaf samples 27 gave positive results. Simple virus infection were realised in 20 samples. 10 times Wheat streak mosaic virus (WSMV), 7 times Wheat dwarf virus (WDV), 6 times Barley stripe mosaic virus (BSMV), 5 times Barley yellow dwarf virus (BYDV), and 1 time Brome streak mosaic virus (BStMV) was detected. Brome mosaic virus (BMV) was detected in 4 samples. Complex infections were detected in 5 samples: in 3 samples WDV and WSMV, and in 1 sample WDV, WSMV and BYDV, and in 1 sample BMV, WDV and BYDV. After the first investigation other samples were collected, in order to continue the examination. These results indicate that Panicum miliaceum can play a major role in the distribution of different cereal virus species.