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[ObjectivesJ The aim of the present study was to explore the potential of two pigment synthesis inhibitors, pyraclonil and isoxaflutole, in the control of herbicide-resistant grass weeds in wheat fields. [Methods ] The activity of pyraclonil and isoxaflutole against resistant grass weeds in wheat field, the saf.ety to different wheat varieties, and the toxicity of the screened herhicide-safener combinations to the weeds in wheat fields were detennined by whole plant determination. [ Results J It was found that pyraclonil ( 210 g · hm -2 ) could cause fresh weight inhibition more than 90% for the fonoxaprop-P-ethyl-resistant Alopecurus japonicus population JCJT -2, the mesosulfuron-methyl-resistant A. aequalis populations JTJT-1 and the fonoxaprop-P-ethyl-resistant Beckmannia syzigachne population JYGC, hut it was not safe to wheat. However, when pyraclonil ( 210 g · hm -2 ) was applied with mefonpyr-diethyl, pyrimidine and isoxadifon-11hyl at 6.57 g · hm -2 respectively, the fresh weight inhibition of 'Zhoumai 27' would he less than 1 %. Meanwhile, the combination of pyraclonil with safeners could still inhibit the fresh weight of JYGC by 100%. lsoxaflutole ( 300 g · hm -2 ) could reach more than 80% fresh weight inhibition to JCJT -2, JYGC and JTJT-1, hut it was not saf"e to wheat. When isoxaflutole ( 300 g · hm -2 ) applied with isoxadifon-ethyl acid at the range of 9.38-37.50 g· hm -2, the fresh weight inhibition rates to' Anke 1401' population were less than 5%. And the combination of isoxaflutole with safeners could still inhibit the fresh weight of JTJT-1 by 90%. It was also found that the combination of pyraclonil+mefonpyr-diethyl(210 g·hm -2 +6.57 g·hm -2 )exhihit high toxicity to all the tested weeds except for Lolium multifiorum and Bromus japonicas. And the combination of isoxaflutole+isoxadifon-ethyl ( 300 g · hm -2 +9.38 g · hm -2 ) exhibited high toxicity to all the tested weeds except for L. multiflorum, B. japonicas and Geranium carolinianum. [ Conclusions] The inhibitory d:foct of the two combinations on the fresh weight of seedlings of some wheat v;u-ieties could be greatdy 1uluced compared \Vith the herbicides themselves. And these two combinations exhibited high toxicity to three resistant grass weeds populations (JYGC, .IT.TY - l and .TC.TT -2) as wdl as to several common weeds in wheat fidds, which suggested the potential to he IL~ed to control weeds in wheat fidds. [ABSTRACT FROM AUTHOR]