刺梨白粉病的发生发展及其防治试验

Studies on the Occurence, Development and Control of Rosa roxburghii Powdery Mildew

刺梨(Rosa roxburghii Tratt.)是一种灌木果树,果实中维生素C含量很高,具很高的经济、观赏价值。近年来,在陕西省汉中、商洛地区大面积人工栽培刺梨,在栽培区普遍发生白粉病(Sphaerotheca pannosa(Wallr.)Lev),危害新梢、蕾、花和幼果,造成减产,严重时新梢枯死。目前,国内外对此病的研究报道甚少。为此,于1988～1990年对该病的危害和病原菌的形态、发生发展规律及防治措施进行了研究。

Powdery Mildew of Rosa roxburghii Tratt. is caused by Sphaero-theca pannosa (Wallr.) Lev., cleistothecium has not been yet discovered in Xian. Hypha overwinters in the bud scale as primary infection source. Conidia are disseminated by wind. The incubation period is about 4~5 days. The disease occurs in the middle of April, 2 peaks of the disease occur in May^June and September^October. The factors affecting the disease occurence are temperature and relative humidity. The disease can be controlled by 25% Triadimefon. Chemicals such as 50% Topsin,Antimycin 120 and Antibiotic Bo-10 also showed a certain degree of control efficiency.