The Survey On The Banana Fungus Diseases In Hainan Island And The Research On The Biological Characteristics Of Curvularia Lunata

The fungus diseases are the important hinders of banana production in Hainan Island, China. On the purpose to obtain the information of the disease occurrence and category used for the banana producers, disease quarantine, science and education, a survey on the banana fungus diseases and the pathogen identification were carried out during 2004～2006 in the banana cultivation areas in Haikou, Danzhou, Ledong, Dongfang, Sanya, Tunchang, Lingao, Chengmai, Qionghai, Wenchang, Baisha, Hainan province, China. A total of 15 fungus diseases on banana were discovered and 16 pathogens were identified. Details are as followings: Panama disease (Fusarium oxysporum Schlecht.f.sp.cubense), anthracnose (Colletotrichum musae), Alternaria leaf spot(Alternaria alternata), Curvularia leaf spot(Curvularia lunata,Curvularia senegalensis), Cordana leaf spot(Cordana musae), Mycosphaerella leaf spot(Mycosphaerella musicola), Deightoniella leaf spot(Deightoniella torulosa),Black star disease(Macrophoma musae), Soft rot(Rhizopus stolonifer), Banana blast (Magnaporthe grisea), Fusarium crown rot (Fusarium.moniliforme), Cladosporium leaf spot (Cladosporium musae), Aspergillus disease(Aspergillus niger), Corynespora leaf spot (Corynespora cassiicola) and Nigrospora leaf spot (Nigrospora sphaeri)。On the basis of the above results, the pathogen of Curvularia leaf spot(Curvularia lunata, CL) was chosen for further study on the Biological Characteristics and the sensitivity to fungicides because of its potential damage on banana in Hainan Island. The results showed that the mediums suitable for the mycelium growth of CL included PSA, PDA and OMA, the temperature suitable for the mycelium growth,sporulation and conidium germination of CL was 25～30℃, the carbon and nitrogen sources suitable for the mycelium growth and sporulation of CL included sucrose, glucose, carbamide, potassium dihydrogen and sodium nitrate, the acidity suitable for the mycelium growth, sporulation and conidium germination of CL was pH5～9. Though RH≥80% was suitable for conidium germination of CL, germination rate was higher as RH increased. The effect of light on the mycelium growth was not obvious,however, alternation of light and dark was good for sporulation of CL. The lethal temperature for conidia was 55℃(10min). The test on the sensitivity of fungicides on CL showed that several fungicides including Tebuconazole, Propiconazole, Prochloraz, difenoconazole were able to inhibit pathogen mycelial growth.