The aim of the research was a comparison of soil seed bank, formed by the influence of different crop production systems (organic, integrated, conventional and monoculture of winter wheat) with weed infestation in the winter wheat. The study was conducted at the Experimental Station of the Institute of Soil Science and Plant Cultivation – State Research Institute in Osiny (Lublin province), where these crop production systems, characterised by different crop rotations and agricultural practices, have been compared since 1994. The assessment included the analysis of weed species composition and the number of weeds in winter wheat cultivated in different crop production systems as well as the weed seed stock in the 0–20 cm soil layer under winter wheat. The soil seed bank and winter wheat infestation was analysed using ecological indices: Shannon's diversity index (H') and Simpson's dominance index (SI).
The number of weed seed species in the soil was higher than the number of weed species in a winter wheat canopy in all compared systems. The difference between the number of species in a canopy and in the soil was the smallest in the organic system. The monoculture of winter wheat was characterised by the lowest diversity of weed flora and soil seed bank. Shannon and Simpson indices showed the bigger similarity between soil seed bank and weed infestation in the organic system and the lowest in conventional one and monoculture. Small differences of species number in weed seed stock in the compared systems and the narrow ranges of Shannon and Simpson indices suggest smaller dynamics of change of soil seed bank than weed flora.