TRANSLOCATION OF GLYPHOSATE, QUIZALOFOP, AND SUCROSE IN QUACKGRASS (ELYTRIGIA-REPENS) BIOTYPES

The translocation pattern and distribution in rhizomes of C-14-glyphos ate, C-14-quizalofop, and C-14-sucrose was examined in five quackgrass biotypes. Translocation of radioactivity in the different plant parts varied among biotypes. Translocation in the whole plant after treatme nt with the three C-14-chemicals varied among biotypes but was not cor related with their tolerance to herbicides. Detailed analysis of distr ibution of radioactivity in the primary rhizome showed that more 14C w as found in the apical sections after treatment with C-14-sucrose. A s imilar pattern was observed after C-14-glyphosate application with all biotypes except one. Very low radioactivity was found in rhizomes aft er C-14-quizalofop application, but a preferential accumulation in api cal sections of the primary rhizome was detected in two biotypes. The tolerance of one biotype to glyphosate was explained by the absence of radioactivity accumulation in the apical sections of the rhizome.