Researches On The Pathogen Identification Of Jujube Tree Bark Blister Blight And Its Control

Blister bark spot of Jujube, a new serious disease has taken place in recent years in Binzhou city Shandong province. The jujube branches were mainly harmed, so the cormus interior turned yellow, and the bark cracked in serious branches. The yield and quality of jujube were affected by decreased growth and armor mouth cicatrization, causing great economic loss. The cause, occurrence and prevention of the disease hasn't been reported to date.Investigations among Shandong Binzhou counties areas during 2004～2005,242 isolates from 52 infected"Dongzao"jujuba tree bark among 16 batches were selected,Based on its separation character and the shape characteristic, the preliminary determination is Phoma persicae,Alternaria sp,Fusicoccum sp. 3 Taxonomical units。Uses alone or the simultaneous inoculation carries on the pathogenic determination to 3 separations,finally indicates only then Phoma persicae to vaccinate alone successfully,and can cause the typical symptom. The cause of disease determination is Phoma persicae Sacc.The disease of Blister bark spot in Jujube began when the jujube germinates in April, and reached its top when the jujube blossoms and fruits in June, and declined slowly with the higher temperature in July and August, and reached its second peak in september and early october.The mycelial growth,Phoma persicae growth are good in the PDA medium,OUA medium,CMA medium.For the mycelial growth of Phoma persicae ,the optimum temperature was 20~28℃,the optimum pH value was 6~7,the treatment of alternate light and darkness,darkness have significant effect on the mycelial growth. For the sporulation, the optimum temperature was 25℃,the optimum pH value was 6~7, sporulation light had no effect, the optimum solution was jujube juice.The bio-assessment tests of different fungicides showed thas difenoconazole,Azoxystrobin and Kejunkang were the best for controlling the disease.