The Influence of Intercrops Biomass and Barley Straw on Yield and Quality of Edible Potato Tubers

Potatoes destined for direct consumption should be distinguished by a high trade yield with the best qualities. (Leszynski, 2002; Boliglowa and Glen, 2003; Plaza and Ceglarek, 2009). In most European countries schemes for the verifiability of the potato product are introduced. The aim is to obtain good quality of potatoes, ensuring the reduction of harmful substances to human health and the natural environment (Spiertz et al., 1996). The beneficial effects of organic fertilization is noted here (Leszczynski, 2002; Boliglowa and Glen, 2003; Makaraviciute, 2003; Plaza et. al., 2009). Farmyard manure is a basic manure applied in potato cultivation (Batalin et.al., 1968; Kalembasa and Symanowicz, 1985; Rozrtopowicz, 1989). For many years its amount covered the demand, but now the situation has negatively affected due to the decline in livestock, especially cattle. Decreasing amount of farmyard manure, low profitability and the rationale for a system of integrated agriculture, tend to seek alternative, energy-efficient sources of biomass. As a result, a significant role is being attributed to green manures (Grze]kiewicz i Trawczynski, 1997; Zając, 1997; Ceglarek et. al., 1998; Karlsson-Strese et. al., 1998; Plaza i in., 2009). Green fertilizers were mentioned many times in literature. Batalin et. al. (1968), Roztropowicz (1989), Gruczek (1994), Dzienia and Szarek (2000) emphasize that the advantage of using this type of fertilization is high labor and energy saving in relation to its amount spent on works related to the application of farmyard manure. Estler (1991), Stopes et. al. (1995), Spiertz et. al. (1996), Karlsson-Strese et. al. (1998) and Songin (1998) show that the intercrops introduction into the cultivation is not only the production of biomass. They are also a kind of absorbent material to prevent leaching of nutrients into the deeper layers of soil and groundwater, which is important in protecting the agricultural environment. From manuscripts connected with green fertilizers it is clear that among catch crops, undersown crops seem to be the cheapest source of organic matter because it does not require any additional costs associated with the cultivation and preparation of the soil before sowing, which is particularly troublesome in the cultivation of stubble crops (Ceglarek et. al., 1998). Seed cost is also low. As undersown the legumes are recommended to cultivate. The Renaissance intercrops from legumes is linked to the multilateral noticing