Abstract
dc:description.abstractTo combat excessive vine vigor, many vintners have employed intensive cover cropping techniques. While cover crops provide a multitude of benefits to the farming system, they can compete for nutrients and water. The seemingly ubiquitous adoption of cover crops in the Eastern United States has led to vines and grape musts which are deficient in nitrogen (N). A must that is deficient in yeast assimilable nitrogen (YAN) can lead to the production of off aromas and stuck or sluggish fermentations. It has also been suggested that musts with limited amino nitrogen sources can result in wines with less fruity aromas than those with a higher starting amino acid content. Varying rates of calcium nitrate were applied to the soil at bloom and foliar urea was sprayed at a Sauvignon blanc and Petit Manseng (Vitis vinifera L.) vineyard. Perennial White and Crimson clover as well as foliar urea applications at v ér a i s o n were utilized at a Vidal blanc (Vitis spp.) site. Foliar urea was effective at significantly increasing YANs in all experiments with some year to year variation in efficacy. Foliar urea applications slightly favored the production of ammonia over primary amino nitrogen. While most of the measured amino acids in fruit increased in concentration with the application of either soil or foliar N, foliar applications were more effective at increasing fruit amino acids. Of the amino acids measured, arginine and glutamine were the most increased by foliar urea applications, whereas proline was relatively unaffected. The use of clover as a perennial under-vine cover crop did not increase berry YAN. The application of foliar urea sprays may present an effective means by which vintners can easily increase must YANs and amino acid contents.
Degree
thesis:*- Name thesis:degree_name
- Master of Science in Life Sciences
- Level thesis:degree_level
- masters
- Discipline thesis:degree_discipline
- Food Science and Technology
- Department dc:contributor.department
- Food Science and Technology
- Grantor dc:publisher
- Virginia Tech
- Year dc:date.issued
- 2016
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Moss, James Russell
- Chairs dc:contributor.committeechair
-
- Wolf, Tony K.
- Stewart, Amanda C.
- Committee members dc:contributor.committeemember
-
- Okeefe, Sean F.
- Peck, Gregory M.
Subjects
dc:subject × 5Rights
dc:rights- Statement dc:rights
-
- In Copyright
- Licence dc:rights.uri
- Language dc:language.iso
- en_US
Identifiers
dc:identifier.*- Dc Identifier Other
- etd-08122016-204502
- OAI identifier oai:identifier
- oai:vtechworks.lib.vt.edu:10919/78150