Glyphosate is post-emergence herbicide commonly used in perennial weed
control as foliar active compound. Thus recent approaches are aiming to minimize
its usage even in amounts and numbers. The role of fourteen chemical adjuvants in
enhancing or reducing the efficiency of giyphosate on nutsedge (Cyperus roiundus)
as a dominant perennial weed was studied. The adjuvants used were: glue.
ammonium sulfate, urea. diethyl ether. propanol. rape seed oil. castor oil, paraffin
oil. diesel oil. mineral oil, monoethylene glycol dioleate. monoethylene glycol
monoleate and glycerin. The efficacy of half rate of glyphosate with and without
adjuvants compared with glyphosate recommended rate without adjuvants was
evaluated on yellow nutsedge grown in pots under greenhouse conditions. The
reduction percentages in weed population by the tested compounds were
calculated as ratios from untreated control treatment. Using adjuvant in binary
mixture with glyphosate resulted in high reduction in weed growth parameters. The
maximum reduction was recorded with glycerin and followed by the surfactants
monoleate. dioleate and sticking agents such as glue. urea. whereas the crop seed
oil and petroleum oil came in the second category in relation to glyphosate
efficiency against weeds as indicated by weed seedling parameters. i.e. fresh and
dry weight. total chlorophyll and carbohydrates contents.