The Identification Of The Main Pathogen Of Frangipani Diseases In Guangxi

The frangipani (Plumeria rubra),belonging to family apocynacea and genus Plumeria. It is mainly distributed in provinces such as Guangxi, Fujian,Yunnan and so on in China. The diseases of frangipani occurs in Guangxi province, is mainly caused by the infection of fungus. These diseases make great influence on frangipani’s ornamental value and also on frangipani’s yield as a medicinal plant. I conducted a survey of frangipani diseases in Guangxi province from2011to2012, and clear and definited the pathogen of major diseases. The results of the reserch obtained are as follows:1. The species of frangipani diseases in Guangxi province have been preliminary clear,they mainly are:frangipani anthracnose, frangipani rust, frangipani brown patch, frangipani black spot, frangipani leaf blight, frangipani leaf crinkle, frangipani mosaic. Different kinds of spots emerge on the leaf or flower after infected with frangipani disease. The most universal and serious diseases are frangipani anthracnose and frangipani rust. In addition, the harm caused by some frangipani diseases in local area are also very seriously, such as the frangipani leaf crinkle in Baise city. All the diseases have been discoverd was recorded and reported for the first time in Guangxi province.2. Preliminary clear that the damage and distribution of frangipani disease in Guangxi province. Frangipani anthracnose is distributed in most of the places in Guangxi province, And it’s the most serious frangipani disease in Guangxi province. The distribution of frangipani rust in Guangxi province shows a degree of regularity.3. This study focus on frangipani anthracnose, frangipani rust and the morphological characteristics of the pathogen. And the rDNA-ITS sequence of the colletotrichum and rust have been identified. The pathogen of anthracnose is ColletotrichMm gloeosporioides (Penz). Sacc. The pathogen of the frangipani rust is Coleosporium plumierae Pat.4. The biological characteristics of the urediospore (Coleosporium plumierae Pat.) have been determined. The urediospore could germinate well on the1.5%water agar but could not germinate in the sterile water. In the temperature range of15-30℃, the germinate rate increase with the temperature,but it made inhibitory effet on the extention of the germ tube. PH6-6.5was the optimum PH for germination. On the condition of the30℃and1.5%water agar, the germination rate increase with time in a time frame. Then it tend to be stable after some time.