Control of Bacterial Blight of Rice by Using Rice Varieties Mixed-Planting

Field experiments of the mixed-and pure-planting of five rice varieties,representing four indica or hybrid varieties and one glutinous rice variety,were conducted to determine the effects of different rice varieties planting combinations and their deployment mode on controlling bacterial blight(BB) of rice.The results demonstrated that mixed-planting of glutinous and indica rice varieties had a greater effect on reducing the incidence and severity of rice BB than the pure-planting of these varieties,particularly for glutinous cv.Huangkenuo,with maximum control efficiencies of 52% and 86.4%,while 59.3% and 66.6% on indica rice varieties in mixed-planting compared with their pure-planting in 2005 and 2006,respectively.Meanwhile,different planting combinations of rice varieties showed a different control efficiency against the rice BB.The distance of the rice BB progressed in different mixed-planting plots was reduced by 21.8%-59.2% compared with the pure-planting plots.It was showed that the ratio between glutinous and indica rice variety cultured in mixed-planting plots also affected the control efficiency against the rice BB,the best ratio for cultivation between glutinous and indica rice cultivar was 1 row∶6 rows,which would provide the best control efficiency for rice BB.