Influence of simulated imazethapyr soil residues on the whole protein content in different crops roots

Abstract

The bioassay conducted in controlled conditions was used to investigate the sensitivity of selected crops (maize, sunflower, wheat, sugar beet, oilseed rape and mustard) to imazethapyr carryover. The dešendence of whole protein content in test plants roots was measured in regard to different imazethapyr concentrations in the soil. The rates of imazethapyr were established at 240, 120, 60, 30, 15, 7.5, 3.75 and 1.875 mg A.I. kg-1 soil (ppbw). After sowing, the plants were grown in a growth chamber for 14 days and afterwards carefully removed from the pots intact, while the soil was removed from the root system by gentle and thorough washing. Whole protein contents were established based on the nitrogen content in roots using distillated method. Each treatment was performed in four replications and bioassays for each plant species were repeated twice. Statistical analysis of the whole protein content was based on ANOVA, and Tuckey test was used to determine the significant differences. There was no dependence of the whole protein content on herbicide concentration. A slight increase of the whole protein content was determined in maize roots. The same goes for sugar beet, mustard and oilseed rape. In wheat roots and sunflower roots there were a decrease in the whole protein content for some treatments in comparison to control (imazethapyr concentrations ≥ 15 mg A.I. kg-1 soil, for wheat and ≤ 7.5 mg A.I. kg-1 soil, for sunflower). If results obtained in this study are considered together with earlier established level of sensitivity to imazethapyr, one can say that in highly sensitive species there is always an increase in the whole protein content in herbicide treatments when compared to the control. In wheat roots (the least sensitive of plant species tested here) a decrease of the whole protein content was observed and only for higher herbicide concentrations.