Influence of weediness and different between-row spacing on yield and yield components of soybean

U radu je praćen utjecaj zakorovljenosti i međurednog razmaka sjetve na prinos i komponente prinosa soje, sorte IKA (Poljoprivredni Institut, Osijek). Istraživanje je izvršeno u 2016. godini, na području Vukovarsko-srijemske županije sjetvom soje na međuredne razmake od 25 cm, 50 cm i 70 cm. Rezultati su pokazali da se prosječni prinos zrna soje statistički značajno razlikovao između ispitivanih tretmana sjetve. Najviši prinos ostvaren je pri međurednom razmaku sjetve od 70 cm (582,15 g/m2). Razlike u prinosu soje sijane na međuredni razmak 25 cm (478,22 g/m2) i 50 cm (429,94 g/m2) nisu bili statistički opravdane. Na kompeticiju s korovima najosjetljiviji je bio međuredni razmak sjetve od 25 cm, gdje se značajan gubitak prinosa uočava odmah nakon sjetve, odnosno već tijekom nicanja. Međuredni razmak sjetve soje od 50 cm najbolje je podnosio kompeticiju s korovima u ranim fazama razvoja, tako da je prvi veći gubitak prinosa zabilježen tek nakon četrdesetog dana od sjetve. S međurednim razmakom sjetve soje od 70 cm, iako je ostvaren najveći prosječni prinos po m2, vrlo brzo je došlo do smanjenja prinosa već na početku sezone (dvadeset dana nakon sjetve, u vrijeme nicanja i soje i korova). Dužina zakorovljenosti signifikantno je utjecala na komponente prinosa, tako da se s produženjem trajanja zakorovljenosti vrlo signifikantno smanjivala hektolitarska masa zrna soje kod sva tri međuredna razmaka sjetve (25, 50 i 70 cm). Za masa 1000 zrna utvrđena je slaba korelativna veza, jedino kod međurednog razmaka sjetve od 70 cm.This study evaluates influence of weediness and different between-row spacing on yield and yield components of soybean variety IKA (Poljoprivredni Institut Osijek). Research was conducted in 2016. on Vukovar-Srijem county sowing the soybean at 25, 50 and 70 cm between rows. Results showed significant yield differences between investigated sowing treatments. The highest yield (582,15 g/m2) was obtained on plots with 70 cm between-row spacing. Differences in yield between 25 cm (478,22 g/m2) and 50 cm (429,94 g/m2) row spacing were not significant. The most sensitive sowing treatment regarding the duration of weed competition was narrowest (25 cm) row spacing, where decrease on yield was noticed soon after sowing, during the emergence period. The best option was 50 cm between-row spacing. Soybean compete well with the weed in early stages, and beginning the yield loss was noticed after 40 days from sowing. Although the highest yield per m2 was achieved with widest row spacing (70 cm), this sowing treatment due to weed competition began to receive yield loss early in the growing season (20 days after sowing). Length of weediness significantly influenced yield components as well. With prolonged period of weed competition hectoliter mass significantly decreased in all investigated row spacing treatments. However, 1000 kernel weight showed low correlation relationship on yield and length of weediness only in widest row spacing (70 cm)