Abstract
When MCC was incorporated into the root zone and shoot zone of the soil sown rice plants and barnyardgrass, the following observations were obtained.
(1) It was discovered that in both the root zones and the shoot zones swep was more toxic to barnyardgrass than rice plants. In rice plants the toxicity was almost the same in both zones, but in the case of barnyardgrass, the toxicity of swep was much stronger in the shoot zone than it was in the root zone.
(2) On the selectivity of swep it was shown that in both rice plants and barnyardgrass the selectivity was not too high when the treatment was made in the root zone. However, there obtained a high degree of selectivity when the treatment was made in the shoot zone. In the case of the shoot zone, the selectivity was much higher when the treatment was made in the upper layer of the shoot zone than in the lower layer of it.
