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(一)水稻病虫。二化螟:越冬基数较常年偏低,但冬季少雨,气温正常,有利幼虫越冬,死亡率低,据气象予报陕南四、五月份降水正常略偏少,予计气温回升较快,螟虫较常年提早3～5天,为害较集中,比1972年重,属中常偏重年份。第一代螟蛾盛发期,安康为5月上旬,汉中为5月中旬,商县及关中稻区为6月上旬。枯心苗率一般是:安康1～2％;汉中2～3％;商县及陕南山区3％左右。总的是,山区重于平川。早禾田重于晚禾田,秈稻重于粳稻,枯鞘率多于枯心苗率。
(A) rice pests. Chilo suppressalis: overwintering base is lower than normal years, but the winter is dry, the temperature is normal, the favorable larva overwinter, the mortality rate is low, according to the meteorological report to the southern Shaanxi April and May precipitation is slightly less normal, the temperature is expected to rise rapidly, More than usual perennial 3 to 5 days, more concentrated damage, heavier than in 1972, is a medium-term emphasis on the year. The first generation of moths Sheng period, Ankang in early May, Hanzhong in mid-May, Shangxian and Guanzhong rice in early June. Cessation of seedling rate is generally: Ankang 1 ~ 2%; Hanzhong 2 ~ 3%; Shangxian and Shannan mountain about 3%. The overall point is that mountains are heavier than Hirakawa. He Hetian heavier than late Hetian, indica rice is more important than japonica rice, more than the rate of dead wood sheath disease.