Search

Detached Vitis vinifera 'Cabernet Sauvignon' berries (12.5° Bé) were inoculated either singularly or in combination with spore suspensions of Botrytis cinerea, Colletotrichum acutatum and Greeneria uvicola and the degree of disease expression examined at either 20 or 27 °C. Berries were more susceptible to B. cinerea at 20 °C and to G. uvicola at 27 °C but were highly susceptible to C. acutatum at either temperature. In experiments involving inoculation of berries with mixtures of fungal organisms, B. cinerea infection was diminished at 27 °C by either C. acutatum or G. uvicola but only by C. acutatum at 20 °C. G. uvicola infection was diminished by C. acutatum at both temperatures investigated. B. cinerea reduced the level of infection of both C. acutatum and G. uvicola at 20 °C. The findings have implications for seasonal bunch rot management of grapes in relation to predicted changes in global temperature., VITIS - Journal of Grapevine Research, Vol. 50 No. 2 (2011): Vitis

Colletotrichum acutatum, the casual agent of ripe rot in tropical and sub-tropical grape growing regions of Australia, affects crop yield and wine quality. To elucidate the epidemiology of the fungus, its presence was studied on shoots, pea sized and mature berries, mummified bunches, spurs and canes during two consecutive growing seasons and one winter season. The presence of C. acutatum was analysed by both traditional and real-time PCR methods. A protocol was developed to achieve PCR amplification for fungal DNA extracted from 'difficult' wood samples. C. acutatum was detected on mature berries, mummified berries, the peduncles of mummified berries, winter spurs and canes but not on the remaining analysed tissues. Thus the fungus overwinters on Vitis vinifera plant tissues and the conidia on spurs and dormant wood are likely to be the most important source of primary inoculum for the next growing season., VITIS - Journal of Grapevine Research, Vol. 51 No. 1 (2012): Vitis