DOI: 10.5061/dryad.3ffbg79m8
title: Increases in vein length compensate for leaf area lost to lobing in grapevine

description: There is considerable variation in leaf lobing and leaf size, including
 among grapevines, some of the most well-studied leaves. We examined the
 relationship between leaf lobing and leaf size across grapevine
 populations which varied in extent of leaf lobing. We used homologous
 landmarking techniques to measure 2,632 leaves across two years in 476
 unique, genetically distinct grapevines from 5 biparental crosses which
 vary primarily in the extent of lobing. We determined to what extent leaf
 area could explain variation in lobing, vein length, and vein to blade
 ratio. Although lobing was the primary source of variation in shape across
 the leaves we measured, leaf area varied only slightly as a function of
 lobing. Rather, leaf area increases as a function of total major vein
 length, total branching vein length, and decreases as a function of vein
 to blade ratio. These relationships are stronger for more highly lobed
 leaves, with the residuals for each model differing as a function of
 distal lobing. For a given leaf area, more highly lobed leaves have longer
 veins and higher vein to blade ratios, allowing them to maintain similar
 leaf areas despite increased lobing. These findings show how more highly
 lobed leaves may compensate for what would otherwise result in a reduced
 leaf area, allowing for increased photosynthetic capacity through similar
 leaf size.
description: Leaves were sampled from seedlings of five
 biparental <em>Vitis</em> populations located in Madera
 County, California. Leaf samples were collected on June 22 and July 12,
 2018, then again in 2019 on June 14, 19, and July 5. Across the sampling
 dates within a given year, a total of three mature, representative leaves
 were sampled from each of the vines and placed into labeled plastic bags.
 The plastic bags were stored in a cooler during collection and scanned,
 vein side down, later the same day using a flatbed scanner. Files were
 saved as JPEGs and named using the accession ID.  Each seedling was a part of one of five biparental
 crosses. These populations included: 125 individuals from a DVIT 2876 x
 unnamed <em>Vitis vinifera</em> selection cross (Pop1), 100
 individuals from a DVIT 2876 x a different unnamed Vitis vinifera
 selection cross (Pop2), 150 individuals from a DVIT 2876 x unnamed
 <em>Vitis</em> hybrid cross (Pop3), 75 individual from a DVIT
 2876 x a different unnamed <em>Vitis</em> hybrid cross (Pop4),
 and 50 individuals from a seedling (DVIT 2876 x unnamed <em>Vitis
 vinifera</em> selection) x DVIT 3374 (<em>Vitis
 mustangensis</em> Buckley) cross (Pop5). The scan filename is the
 accession number, with each scan located within a subfolder labeled for
 the date of sampling (labeled “20180622” for 22 June 2018, “20180712” for
 12 July 2018, “20190614” for 14 June 2019, “20190619” for 19 June 2019,
 and “20190705” for 5 July 2019. The accession names and associated
 population are listed in the associated metadata sheet
 “vitis_crosses_key.csv”. Note that leaves were not available for all
 accessions in both years, so some accessions may not include scans from
 2018, 2019, or both. 
description: This is a repository of grapevine leaf scans
 of <em>Vitis</em> crosses located in Madera County,
 California. Leaf samples were collected on June 22 and July 12 2018, then
 again in 2019 on June 14, 19, and July 5. Across the sampling dates within
 a given year, a total of three mature, representative leaves were sampled
 from each of the vines. On each scan, there is a printed label indicating
 the name of the seedling, the position in the vineyard (row and vine
 number) and the year of sampling. Labels were printed in advance so the
 exact date of sampling listed in the scan may not be accurate, and the
 sub-folder which the scan is found in should be used for this information
 instead. The scan filename is the accession number, with each scan located
 within a subfolder labeled for the date of sampling. The subfolders for
 each of the dates are labeled as follows: “20180622” for 22 June 2018,
 “20180712” for 12 July 2018, “20190614” for 14 June 2019, “20190619” for
 19 June 2019, and “20190705” for 5 July 2019 The accession names and
 associated population are listed in the associated metadata sheet
 “vitis_crosses_key.csv”. Note that leaves were not available for all
 accessions in both years, so some accessions may not include scans in
 2018, 2019, or both.