ISHS Acta Horticulturae 689: VII International Symposium on Grapevine Physiology and Biotechnology
FACTORS INFLUENCING PRIMARY BUD NECROSIS (PBN) IN AUSTRALIAN VINEYARDS |
| Authors: | C. Collins, B. Rawnsley |
| Keywords: | primary bud necrosis (PBN), ´Shiraz´, pruning, irrigation, shoot growth |
| Abstract:
The compound bud of grapevines contains three buds with the primary bud generally producing the fruiting shoots for the following season. Primary bud necrosis (PBN) is a physiological disorder resulting in the death of the primary bud. It has been associated with a number of factors including high shoot vigor, water stress, shading, excess plant growth regulators and low bud carbohydrates. Microscopic bud dissection used to assess bud fruitfulness for the coming season has highlighted the incidence of PBN. In Australia the cultivar ‘Shiraz’ has displayed the greatest incidence of PBN. Buds dissected during the 2002/2003 growing season revealed that PBN would occur in ‘Shiraz’ around anthesis, which coincides with the rapid period of shoot growth and bud differentiation. Past research indicated PBN ceased when buds entered dormancy, however our findings demonstrated that PBN continues to increase until leaf fall. These studies are continuing along with the timing and incidence of PBN in a number of different wine grape cultivars during the 2003/2004 growing season. Appropriate management strategies, such as modifying pruning levels, are being investigated to minimize the incidence of PBN in susceptible vineyards. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
