Abstract
This study was conducted to clarify the effect of the combination from atrazine and chlorophthalim on their herbicidal activities. An synergistic action from this combination was found in the herbicidal activity against several weed species. Crabgrass of 1.5 leaf stage was not controlled by atrazine at the dosage of 80 g/10a or by chlorophthalim at the dosage of 240g/10 a. However, the combination from atrazine, 40g/10a, and chlorophthalim, 120g/10 a, controlled it perfectly.
Furthermore, bluegrass of 4.5 leaf stage could be controlled by the cmbination.
pre-emergence herbicidal activity of the combination using three different soils was tested and it was found that the activity decreased with increase of clay content. From this, these herbicides may be adsorbed well by the clay.
pre-emergence application on fourteen weed species in a field trial, dayflower, crabgrass, foxtail and ladythumb were not controlled by atrazine at the dosage of 60g/10a, and dayflower, chickweed, knapweed, marshess and ladythumb were not controlled by chlorophthalim at the dosage of 150 g/10a. However, aforementioned combination from atrazine and chlorophthalim controlled all weebs except dayflower.
Phytotoxicity on turf grass (Zoysaa matrella) was not recognized even at the dosage of 100g/10a of atrazine and 200g/10a of chlorophthalim, respectively. Accrdingly, this herbicidal combi-nation from atrazine and chlorophthalim was found to be favourable for weed control in turf.
