Vascular bundles are the main transport channels of water and nutrients into grape berries, and play a very important role in fruit development and quality. During the late ripening stages, water flow through the xylem declines significantly. Phloem transport takes over in supplying water for further growth and water replacement to transpirational loss. Xylem may serve as the channel for water backflow and recycling of excess phloem water. The balance of water dynamics dictates yield and fruit quality. How the vascular bundles connect from the pedicel into the grape berry at brush zone remains unclear. We used fluorescent microscopy to document the morphology and anatomy of brush zone vascular bundles of four grape cultivars. Fresh and methanol stored berries of Shiraz (BVRC 12 & 1654), Sauvignon Blanc, Ruby Seedless and Flame Seedless were hand sectioned and stained with Aniline Blue Fluorochrome and Acridine Orange respectively. A distinctive change in vascular arrangement from the pedicel into the grape brush zone was apparent in all examined cultivars. At the junction of the receptacle (stem) and the berry pericarp, the vascular bundles exhibited the arrangement where xylem was surrounded by phloem. In the brush zone, the vascular bundles reoriented so that the phloem was situated on the inner side of the vascular bundles. This is the first study to characterise the vascular patterns of the grape berry brush zone of four commercial cultivars.
|Publication status||Published - 2019|
|Event||17th Australian Wine Industry Technical Conference (AWITC 2019) - Adelaide Convention Centre, Adelaide, Australia|
Duration: 21 Jul 2019 → 24 Jul 2019
|Conference||17th Australian Wine Industry Technical Conference (AWITC 2019)|
|Period||21/07/19 → 24/07/19|