Rezerve semena korovskih biljaka u konvencionalnom sistemu gajenja kukuruza

Crop rotation and tillage systems are the most important agrotechical measures that interaction with the suppression of weeds and affect the size and composition of the weed seed bank and are in direct correlation with their content in the soil. Knowing seed bank, as well as monitoring the dynamics of the appearance of weed species, constitute the basis for planning and implementation of measures for their effective suppression. The paper presents the evaluation of weed infestation of maize grown in monoculture, 2-year crop rotation (maize, wheat) and 3-year crop rotation (maize, soybeans, wheat) on long-term experiment "Crop Rotation" of the Institute of Field and Vegetable Crops in Novi Sad. Soil samples, taken after the harvest of corn from a depth of 0–15 cm, 15–30 cm and 30–40 cm, were used for the analysis of weed seed bank. By applying the methods of physical extraction, soil samples were irrigated through a system of sieves of different sizes, and by using binoculars and a guide for the determination, a separate determination of seeds was made. The data obtained made it possible to view the number of seeds present in the soil, as well as the vertical distribution of weed species in both arable and subsoil layer.Plodored i sistemi obrade zemljišta spadaju u najvažnije agrotehničke mere koje u interakciji sa suzbijanjem korova utiču na veličinu i sastav rezervi semena korovskih biljaka i u direktnoj su korelaciji sa njihovim sadržajem u zemljištu. Poznavanje rezervi semena, kao i praćenje dinamike pojave korovskih vrsta predstavljaju osnovu u planiranju i sprovođenju mera za njihovo efikasno suzbijanje. U radu je prikazana procena zakorovljenosti kukuruza gajenog u monokulturi, dvopoljnom (kukuruz, pšenica) i tropoljnom plodoredu (kukuruz, soja, pšenica) na višegodišnjem stacionarnom ogledu „Plodoredi“ Instituta za ratarstvo i povrtarstvo u Novom Sadu. Uzorci zemljišta uzeti nakon žetve kukuruza sa dubine 0–15 cm, 15–30 cm i 30–40 cm poslužili su za analizu rezervi semena korovskih biljaka. Primenom metode fizičke ekstrakcije, zemljišni uzorci su ispirani kroz sistem sita različite finoće, a korišćenjem binokulara i priručnika za determinaciju izvršena je determinacija odvojenog semena. Dobijeni podaci su omogućili da se prikaže brojnost prisutnog semena u zemljištu, kao i vertikalna distribucija semena korovskih vrsta kako u oraničinom, tako i podoraničnom sloju