Assay of the Activity of Herbicides using Chlorella

The inhibition of Hill reaction of Chlorella pyrenoidosa was investigated to perform comparative activity-tests of herbicides. Hill reaction of Chlorella cells was completely inhibited at the rate of 1ppm of DCMU at which lebel no growth of Chlorella cells occured. Tested compounds which inhibited Hill reaction of Chlorella similarly inhibited Hill reaction of spinach and crabgrass chloroplast at the same dose lebel. It was found that there were close relationships between the herbicidal activity for weeds and inhibitive activity for Hill reaction of Chlorella with tested photosynthesis inhibitors.