| 論文英文摘要 |
Fruit black rot of wax apple is a common disease. The initial symptom is a water soaking lesion. Later, the lesion expands over the entire fruit. As a huge amount of black pycnidia is produced on the surface of infected fruits, the fruit become black. The diseased fruit graduately lose water and eventually become mummified. This study isolated pathogens of diseased wax apples collected from Kaoshung, Chiayi, Natou and Pintung. Artificial inoculation confirmed that all isolates were pathogenic. All pathogens were morphologially identified as members of Lasiodiplodia and Neofusicoccum. Further identification was carried out by multigene sequence analysis based on sequences of internal transcribed spacer (ITS), β-tubulin (TUB2), translation elongation factor 1-alpha (TEF1α), and RNA polymerase subunit II (RPB2). Three species were revealed: L. theobromae, L. pseudotheobromae, and N. parvum. Virulence of the representative isolates of each specie was compared at different temperatures. L. theobromae and L. pseudotheobromae colonized fruit faster than N. parvum at 32 - 37°C. Colonization of N. parvum was significantly impeded at 37°C. The three species displayed comparable virulence at 24°C, decreased colonization at 16°C, and complete loss of infection ability at 8°C. This is the first report globally that L. pseudotheobromae and N. parvum cause fruit rot of wax apple. |