Effect of silicon content of rice plants on blast resistance at the seedling stage
2004
Hayasaka, T.(Yamagata-ken. General Agricultural Research Center (Japan)) | Fujii, H.
In order to clarify the effective control of rice blast disease at the seedling stage, absolute SiO2 content of rice plant could resist the blast disease was investigated using various rice cultivars and soils. The number of rice seedling blast decreased when blast-infested seeds were cultivated on the soil to which increasing amounts of silica gel had been added. Nine rice cultivars with different complete resistance genes and different degrees of partial resistance were grown on nursery soils treated with silica gel at many different rates. The rice seedlings were inoculated with Pyricularia grisea to estimate their blast resistance. The degree of resistance to rice blast disease clearly differed among the rice cultivars, regardless of plant and soil silicon levels. There were no significant differences within each rate of SiO2 among the rice cultivars used. However, in all rice cultivars, the number of sporulating lesions per leaf was significantly reduced by increasing the SiO2 content of the rice seedling; the number of lesions was reduced to 5%-20% of the initial number when the seedling SiO2 content reached 5%. The susceptibility to blast disease of rice seedlings grown on eight soils collected from different districts, added varying amounts of silica gel, were compared each other. The number of lesions decreased significantly when the SiO2 content of the seedlings reached 5%. These results suggest that a suitable SiO2 content of the rice plant for control of this disease at the seedling stage under any conditions would be at least 5%.
اظهر المزيد [+] اقل [-]