Zakorovljenost i produktivnost postrnog useva soje u zavisnosti od sistema gajenja

Successful double cropping of soybean is not possible without irrigation, especially under reduced tillage systems. Common application of conservation faming systems and doublecropped soybean production are limited mostly by expensive herbicide treatments. Adoption of advanced growing techniques through narrow sowing and decreased interrow distance are crucial to improve crop competitiveness against weeds. The level of weediness and yield of double cropped soybean have been examined on the experimental field of the Maize Research Institute at Zemun Polje. During the investigation, two different soil tillage systems: conventional and conservation; two interrow distances: 76 cm and 38 cm; and two herbicide treatments were evaluated. The average weediness of doublecropped soybean, expressed as fresh biomass of weeds, was lower under conventional soil tillage than conservation tillage, especially on the variants with narrow row distance and herbicide application. Lower weediness in these specific treatments resulted in a signficant grain yield increase of doublecropped soybean.Za uspešno gajenje soje u postrnoj setvi od suštinskog je značaja primena navodnjavanja i sistema redukovane obrade zemljišta. Faktor koji ograničava širu primenu konzervacijskih sistema gajenja soje je utrošak veće količine herbicida. Kao rešenje nameće se mogućnost gajenja soje pri izmenjenom, tj. smanjenom međurednom razmaku, čime bi se povećala kompetitivna sposobnost useva u odnosu na korove. Ispitivan je nivo zakorovljenosti i rodnost soje na oglednom polju Instituta za kukuruz u Zemun Polju. Tokom istraživanja praćen je uticaj dva sistema obrade zemljišta: konvencionalni i konzervacijski sistem obrade, dva međuredna razmaka (76 i 38 cm) i primene dve kombinacije herbicida. Prosečna zakorovljenost postrnog useva soje, izražena kroz ukupnu svežu masu korova, bila je manja na površini sa konvencionalnom obradom zemljišta u odnosu na redukovanu, posebno na varijanti sa manjim međurednim razmakom i primenom herbicida. Smanjena zakorovljenost na ovim varijantama uticala je na ostvarenje značajno većeg prinosa zrna postrnog useva soje