Project Number: 5306-21220-005-16
Project Type: Specific Cooperative Agreement

Start Date: Sep 17, 2012
End Date: Sep 27, 2015

Objective:
Utilize high resolution computed tomography to elucidate anatomical and physiological characters of grapevine rootstocks associated with biotic and abiotic stress tolerance

Approach:
We will utilize High Resolution Computed Tomography (HRCT- a type of CAT scan) in combination with light and scanning electron microscopy to complete the project objective. Live vines and excised woody stems and roots will be scanned with HRCT at the Advanced Light Source (ALS) facility at Lawrence Berkeley National Lab using beamline 8.3.2. Resultant datasets will be analyzed at ALS and in the McElrone and Walker labs using AVISO software and a powerful PC dedicated to this work. We will first compare the vascular anatomy of grapevine varieties that exhibit Pierces’s Disease (PD) susceptibility, tolerance, and resistance. Accessions of Vitis girdiana and V. arizonica from ARS scientist's collection from the southwestern US will be used for this purpose and will be compared to Lenoir and Blanc du Bois varieties exhibiting PD resistance in TX growing regions. ARS scientist and colleagues recently used HRCT scans of the grapevine vascular system to identify previously unknown structures in the vascular system that have an impact on the plant's ability to prevent pathogen and embolism spread. Examining the internal progression (or lack thereof) of disease development in susceptible, resistant, and tolerant cultivars will provide significant insights into potential breeding targets and possible management strategies. The post doc also will be involved in related efforts to explore how different grapevine accessions/rootstocks respond to drought with specific focus on utilizing HRCT to visualize embolism spread and repair among the plant materials. During the funding period, the post doc will also conduct trial runs to test whether HRCT is a viable technique for studying root pests/pathogens in live, intact plants. Target patho-systems could include: root knot and lesion nematodes, trunk canker pathogens, Agrobacterium and Phytophthora.