Effects of mesosulfuron-methyl on growth and competitiveness of Aegilops tauschii and Triticum aestivum

Abstract

Mesosulfuron-methyl has been widely used in wheat fields to control an annual weed Aegilops tauschii; however, the effects of mesosulfuron-methyl on competition between wheat and A. tauschii is not clear. In the present research, using wheat as an accompanying plant, a comparative pot experiment was conducted to see the effect of mesosulfuron-methyl on the growth and competitiveness of A. tauschii. The result showed that (1) under the CK condition (0 mg m−2, mesosulfuron-methyl), the plant height, tiller number and total biomass of A. tauschii in the mixed group were all significantly higher than those of wheat. This showed that A. tauschii is relatively more resource competitive. The relative yield (RY) of A. tauschii > 1, and the RY of wheat < 1, indicating that the competition between wheat and A. tauschii is less than the intraspecific competition of A. tauschii. (2) Results obtained from the relative electric conductivity (REC), superoxide dismutase (SOD) activity, thiobarbituric acid (TBARS) and chlorophyll content in the group of A. tauschii only and wheat only were judged. In addition, the plant mortality, plant height, tiller number and total biomass change of wheat and A. tauschii in both the single and mixed species situations were also evaluated. From these observations, it is concluded that mesosulfuron-methyl treatment had a certain inhibitory effect on the growth and development of both wheat and A. tauschii. However, compared with wheat, A. tauschii have shown a certain level of resistance to low concentrations of mesosulfuron-methyl.