ISHS Acta Horticulturae 455: V International Mango Symposium
INFECTION PATHWAY OF THE STEM END ROT FUNGUS DOTHIORELLA DOMINICANA IN ‘KENSINGTON’ MANGO FRUIT. |
| Authors: | M. J. Gosbee, G.I. Johnson, D.C. Joyce |
| Keywords: | Mangifera indica, fruit, endophyte, postharvest disease, Botryosphaeria sp. |
| Abstract:
Dothiorella dominicana (Dd) is one of several pathogens causing stem end rot of mangoes in Australia and other countries. Dd is also recovered after triple sterilisation from symptomless seedlings grown from infected fruit, suggesting endophytism. This experiment aimed to trace the infection pathway of the pathogen from the inoculum placed onto the cut stem end of the fruit to the seedling. ‘Kensington’ mangoes obtained from the Northern Territory were inoculated with Dd. Superficial quiescent infections of Dd were controlled by hot water dipping. Fruit were surface sterilised and isolations made from 18 points in the fruit and seed at 0, 1, 2, 4, 6, 8 and 11 days after inoculation. Uninoculated controls were assayed on days 0, 4, 8 and 11. The fungi grew down the vascular tissue into the peduncle (day 2) and pedicel (day 4), and under the skin (day 6). Colonisation preceded lesion development, which began on day 8. The seed was infected firstly through the funiculus (day 6) and endocarp and testa (day 8), then into the embryo (day 8–11) where it caused decay. Seedlings grown from inoculated fruit showed highest recovery of Dd in the connective tissue between the embryo and seedling and the hypocotyl zone. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
