Skuteczność niektórych fungicydów w zwalczaniu chorób powodowanych przez grzyby i ich wpływ na plon ziarna jęczmienia jarego [Efficacy of some fungicides for control of fungi and their influence of seed yield in spring barley]

In 1999–2001, studies were carried out in spring barley with the aim to evaluate the efficacy as well as practical and economic effectiveness of fungicide application to control fungal diseases. The following fungicides were used: prochloraz 30% + carbendazim 8%; flusilazole 12,5% + carbendazim 25%; azoxystrobin 25%; kresoxim-methyl 12,5% + epoxyconazole 12,5%; tridemorf 37,5% + epoxyconazole 12,5%; fluquinconazole 10%; metconazole 6%. The infection of barley leaf surface with fungal diseases ranged from 41,3% to 60,1%. The tested chemicals showed high effectiveness amounting to 31,6% – 92,3%, On average, to 73,9%. All applied fungicides contributed to the seed yield increase from 0,32 t/ha to 1,28 t/ha, on average, to 0,8 t/ha. The defrayal index ranged from 0,9 to 2,4, while the index of chemical treatment profitability – from 2,7 to 9,2.