S. STOYANOVA
Institute of Agriculture and Seed Science “Obraztsov Chiflik”, BG – 7007 Rousse, Bulgaria
STOYANOVA, S., 2015. Efficiency and selectivity of herbicides in spring rape (Brassica napus). Bulg. J. Agric. Sci., 21: 363–366
During 2009–2011 at the Experimental field of IASS “Obraztsov Chiflik” – Rousse a field experiment was conducted with three herbicides in spring rape, including “JURA” and “РАСНА” hybrids. The objective of the study was the efficiency and selectivity of herbicides tested to be determined, being applied at optimal, reduced and duel high doses. It was found out that herbicides pendimethalin at dose of 264 gda–1 a.s. and quizalaphop-P-ethyl at dose of 20 g.da–1 a.s., caused plant damages. Pendymethalin, applied post sowing, before emergence, and tetraloxidim – methyloleat and quizalaphop-P-ethyl in phase 3–5 eaf of weeds and phase “leaf rosette” of the crop, reduced density of annual cereal and broad-leaved weeds up to 100%. The herbicides showed insignificant effects on perennial weeds – up to 57%.