Study of the susceptibility of maize lines to some sulfonylurea herbicides

Maize lines are susceptible to different herbicides, what makes seed production more complicate. The susceptibility is depending in high extent on meteorological conditions. The objective of the study was to investigate genetic variability and correlation between phytotoxicity (EWRC evaluation), alterations in dry matter (DM), phenolics and soluble proteins (SP) in sets of 19 ZP lines, to nicosulfuron and foramsulfuron, with the aim to determine sensitivity of individual lines and the potential tolerance patterns during period 2006-2009. The negative impact of both herbicides reflects through DM increase, but in higher degree in nicosulfuron treatment. They also induced in average SP increase and decrease of phenolic’s content. According to different meteorological conditions present during examined four years, SP increase was followed by increased EWRC values at same lines, opposite to lines in which decrease of SP and increase of phenolic’s level could be tied to potential tolerance, what gives importance to testing of each individual maize line. Special attention must be given to application time (according to meteorological conditions and level of weed infestation). The decrease in SP level and increase of phenolics, together with lower EWRC values observed at some lines could be associated to tolerance patterns what was emphasized particularly during 2009, when visible injuries were absent. [Projekat Ministarstva nauke Republike Srbije, br. TR 31037: Integrated Field Crop Production: Conservation of Biodiversity and Soil Fertility]