Growth and anatomical response of rice and barnyardgrass to molinate under various cropping conditions

Growth and anatomical response of rice and Echinochloa crus-galli to molinate were examined under various growing conditions in the greenhouse after molinate had been applied at 3 kg a.i./ha 7 days after sowing or transplanting. Molinate severely reduced growth of broadcast-sown rice compared to drill-seeded or transplanted rice. This effect was more pronounced under flooded than under dry conditions. Molinate also reduced E. crus-galli significantly and a more pronounced inhibition of growth was observed under flooded than under dry conditions. Visual changes in rice were not observed, but leaf primordia in the leaf sheath developed abnormally following molinate treatment and were kinked in a zig-zag pattern in the leaf sheath. These symptoms were more severe under flooded than under dry conditions.