珠兰花叶斑线虫病症状及发生规律研究

Study on the Symptom and Occurrence Rule of Pearl Orchid Leaf Spot Disease Caused by Nematode

珠兰花叶斑线虫病在歙县珠兰花基地发生严重。通过野外调查和室内观察的方法,研究了珠兰花叶斑线虫病的症状与发生规律。结果表明,珠兰花叶斑线虫病主要危害叶片,初期病斑淡黄色,后变红褐色,病斑逐渐扩大,最后呈深褐色,导致叶片脱落。扩散极快,具有主动侵染能力,初步认为其初次侵染源是病叶中存活的线虫和珠兰花病株上带病的腋芽。研究结果为珠兰花叶斑线虫病的识别和有效控制提供参考。

The occurrence of leaf spot nematode of pearl orchid is serious in the pearl orchid flower base of Shexian County. The symptom and occurrence rule of leaf spot nematode of pearl orchid were studied based on field investigation and laboratory observation. Our results confirm that this disease initially damages the leaf tissue. Leaves spot at the first stage turns pale yellow, subsequently reddish-brown spot and gradually expanding. Then, it turns dark brown, causing the leaf to fall off. The disease spreads very quickly with active infection ability. The preliminary analysis demonstrated that primary infection sources are the nematode living in sick leaves and the leaf bud of pearl orchid infected by the nematode. The results provide references for the recognition and effective control of leaf spot nematode of pearl orchid.