Weed infestation in the stand of milk thistle and infestation in sustainable crop rotation

Abstract

-90 - Acta fytotechn. zootechn., 18, 2015(4) IntroductionWeeds are everywhere. Weeds exist only in relation to us. A weed solution can lead to unforeseen new problems. A plant we may find unsightly might be the very one on which other rely in order to thrive. Its removal can create opportunities for other more noxious plants to prosper (Edwards, 2015).Silybum marianum (L.) Gaertn. -milk thistle -grown as a medicinal plant in several countries, is considered as a weed in pastures and cereal crops but also as an interesting plant for biomass production. As an additional contribution to the full exploitation of such promising species, two Sardinian populations of Silybum marianum were investigated for chemical composition, bioactive compounds and antioxidant properties at vegetative and reproductive stages (Sulas et al., 2015).According to Carpino et al. (2003), milk thistle, as spontaneous weed, is scarcely consumed by large and small ruminants grazing on Mediterranean pastures but an increased animal preference has been observed in Sardinia by local farmers when milk thistle is harvested as silage or hay (Sanna S, pers. comm.). In order to reduce milk thistle biomass, grazing by goat has been suggested for non-crop areas (Khan et al., 2009).However, milk thistle is considered a weed in sowed annual legume pastures (Sulas et al., 2008), waste areas, cereal crops, decreasing wheat yields (Khan et al., 2009), and along roadsides (Karkanis et al., 2011).Milk thistle is a medicinal plant cultivated in agriculture. It is the most researched plant for the treatment of liver disease. The achenes, i.e. fruits of the plant, are commonly used as a medicinal drug; they are the raw material for isolation of different substances with liver-protection activity. Its therapeutic properties are due to the presence of silymarin. The seeds contain the highest amount of silymarin, but the whole plant Weed infestation in the stand of milk thistle and infestation in sustainable crop rotation Štefan Týr Slovak University of Agriculture in Nitra, Slovak RepublicMilk thistle -Silybum marianum (L.) Gaertn. can be a winter annual or a biennial medicinal plant. This study was focused on milk thistle as a weed in the sustainable farming system with the crop rotation of maize for grain, common pea for grain, durum wheat and milk thistle. The assessment of the occurrence of Milk thistle in sustainable crop rotation was conducted at the Experimental Base of Faculty of Agrobiology and Food Resources, Slovak University of Agriculture in Nitra in the years 2013-2015. An actual weed infestation of maize, common pea and durum wheat stands with milk thistle was evaluated before preemergence application of herbicides, in the spring time. Second screening of actual weed infestation of all stands in sustainable crop rotation with milk thistle was done before crops harvest. Screening of each field was made on 1 m 2 area with three replications. The three randomly established sample quadrants were situated minimally 10 m from field margin and apart from e...