A comparison of methods for assessment of soil weed seed-bank in the long-term crop rotation

The aim of the research was to determine which methodological procedure is more appropriate for assessing how the crop rotation affects the composition and size of weed seed bank. A long–standing stationary experiment "Plodoredi" at the Institute of Field and Vegetable Crops in Novi Sad was used for the research. According to the "Square grill" method, the land was sampled with two plots of wheat for 50 years in a monoculture and 3 year crop rotation (winter wheat-corn-soybean). It was sampled in autumn 2014, spring and autumn 2015, and two metrological procedures were used to assess the soil weed seed bank: physical extraction of seed and seedling emergence method. According to the first method, 500 ml of the soil sample was washed with a jet of water through a sieve of a different diameter (2 mm, 200 μm, 500 μm and 800 μm), and separate seeds were determined using the determination keys