Black-spot disease was reported recently occurring on Ziziphus jujuba Mill. 'Dongzao' at Hebei and Shandong province in China. Serious yield loss caused by black-spot disease was reported. From 2004 to 2007, the symptom, harmfulness, and the dominant factor for the epidemic were surveyed in 10 counties or cities of Hebei province, Shandong province, and Tianjin city. The result showed that black-spot disease mainly occurred on fruits of Ziziphus jujuba Mill. 'Dongzao', and the symptom appeared in the first ten day of July. Beige irregular spots first appeared on the surface of the fruits, and then developed to dark round or elliptical lesion with clear or unclear border. The lesions limited at the surface of the fruits while not going into the sarcocarp, and the lesion could be cupped or flat. Some small black spots (pycnidium) appeared above or under the surface of some lesions. Black-spot disease developed to the top during the last ten-day of July or the first ten-day of August, and developed into decline phase in the first ten-day of September. Black-spot disease occurred widely at the 10 counties investigated during 2004 to 2007. The most serious diseased orchards were found at Cangxian County in 2006 and at Botou city in 2007. The disease ratio and disease index in Cangxian (2006) were 45.8% and 51.2, while the disease ratio and disease index in Botou (2007) were 48.1% and 54.9, respectively. Incubation period of black spot disease was investigated in 2006 at Hejian city, Hebei province. Combining with the weather condition of the same period as the disease occurred, disease temporal dynamic of epidemic was analyzed. Rainfall was the key factor of the epidemic of black-spot disease of Ziziphus jujuba Mill. 'Dongzao'.
