一、美軍飞机在朝鲜北部投掷带有大豆紫斑病菌的大豆桿及荚 1952年3月20日下午一時,中國人民志願军某部副政治指導員孙志堅,在朝鲜平安北道定州郡高安面延豐里目睹美軍佩刀式喷氣機四架,並見黑色物體一團降落。該物體在離地面約300公尺處即行散開,渐即見大豆桿,莢及樹葉等紛紛落下。散布的面積約寬200公尺,長500公尺,平均每平方公尺中有大 I. U.S. aircraft threw soybeans and pods with purpura in northern North Korea At about 1 pm on March 20, 1952, Sun Zhijian, a deputy political instructor of the Chinese People’s Volunteer Army, witnessed the attack on Yanfeng, a high-level city in Dingzhou County, North Pyongan Province US Saber jet four, and see a mass of black objects landing. The object is about 300 meters away from the ground that is to disperse, gradually see the soybean stem, pods and leaves have fallen. Spread an area of ​​about 200 meters wide and 500 meters long, with an average of a square meter