Abstract:

The objective of this study was to confirmed control efficacy that the different herbicides combinations were used to control the resistance weed in direct seeding rice fields in the region of Dongting Lake in 2009-2010. The results showed that Echinohloa crusgalli (L.). Beauv. (barnyardgrass) were resistant to quinclorac in the area, The control of double use quinclorac only gave the 53.1% of barnyardgrass plant density control and 65.5% of barnyardgrass plant fresh weight control in the experiment of 2010. The three combination herbicides of 1, 2, 3 in the test gave excellent control effect to resistance barnyardgrass and its population. The control effect was more than 90% to the weed in two years experiments. The three combination herbicides were used with ring application form in different years and to avoid or delay appearing of new resistance weeds. So that, the three combination herbicides should be extension promoting in direct seeding rice area of Dongting Lake.