穗颈稻瘟病是影响后季稻稳产高产的主要病害。1980年后季稻抽穗开花期,遇连续7天低温阴雨,导致穗颈瘟大流行,后季稻成片出现白穗。全郊区约有21万亩稻田颗粒无收,损失粮食约八千多万斤。 (一)穗颈瘟对后季稻产量的影响穗颈瘟的始病期一般在9月下旬,盛发期为10月上旬,少数年份自中旬起急剧加重为害。由于菌源、栽培措施、肥水管理以及感病期的气候条件不同,各年发病程度有很大差异。据市植保站历年考查材料,病穗率小 Blast of rice neck blast is the main disease affecting the stable and high yield of the latter rice. After 1980, the flowering and flowering of Q. rice at 7 consecutive days of low temperature and overcast rain led to pandemic pandemic pandemic, and the latter rice appeared white spike. The whole suburbs of about 21 acres of rice crop failure, loss of food about eight million kilos. (A) of panicle blast on the yield of late rice panicle blast onset period is generally late in September, the peak period of early October, a few years from mid-sharp increase in damage. Due to the different bacterial sources, cultivation measures, fertilizer and water management and the climatic conditions in the susceptible period, the incidence of each year varies greatly. According to the city’s plant protection station calendar examination materials, sick ear rate is small