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1964年春季,河北省平原和山地梨区黑星病普遍流行,平原梨区较一般山地梨区为重。据在定县、曲阳、河间、交河等县部份果园调查,六月份病叶率达52—64%,病果率50—68%,个别重病园病果率高达90%左右。香椿梨、秋梨、鸭梨、酸梨、马蹄黄、瓶梨、土虫梨、砘子梨、雪花梨及夏梨等品种都有不同程度的被害,其中以香椿梨、秋梨、酸梨和砘子梨等发病最严重。邢台市西
In the spring of 1964, scab was endemic in the plains and mountain pear areas of Hebei Province. The plain pear area was heavier than the general mountain pear area. According to the investigation of some orchards in Dingxian, Quyang, Hejian and Jiaohe counties, the diseased leaves rate reached 52-64% in June and the disease-fruiting rate was 50-68%. The prevalence rate of disease in individual seriously ill park was as high as 90%. Pear, Pear, Pear, Pear, Pear, Pear, Pear, Pear, Pear, Pear, Pear, Pear, Pear, Razor pears and other diseases the most serious. Xingtai City West