Temporal and Spatial Blast Incidence in Leading Cultivars and Elite Lines of rice in Korea(II)

벼 주요 품종 및 계통의 지역별, 연도별 도열병 발병 차이(II)

Incidence of blast caused by Pyricularia grisea Sacc. on 21 leading cultivars and elite lines of rice was investigated in different locations such as Icheon, Chuncheon, Jecheon, and Naju during three years from 1991 to 1993. Disease index of leaf blast of Dongjinbyeo was high in the blast nursery with range 4 to 9 at Naju, but low at other locations with range 1 to 4. Percentages of diseased leaf area of Joryungbyeo and Daelipbyeo 1 were 4.3 and 12%, respectively in the fields at Jecheon in 1993, but were much lower in the other locations during three years. The incidences of leaf blast of Daelipbyeo 1 were 0.3 and 12.0% at Chuncheon and Jecheon, respectively in 1993, but no disease occurred at Naju during three years. Percentage of diseased panicles of Joryungbyeo was 100% at Icheon and Jecheon in 1993, 92.4% in Suweon 390 at Icheon on 1991 and 100% in Jinbu 15 at Jecheon on 1993. Race distribution of rice blast fungus at Icheon and Jecheon was more varied than that of the other locations.