Data for: Variation in the role of the flag leaf in the reproductive effort of semi-arid rangeland bunchgrasses
Data files
Apr 10, 2024 version files 80.04 KB
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2020FlagBag.xls
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README.md
Abstract
This is the complete data set used in the manuscript titled "Variation in the role of the flag leaf in the reproductive effort of semi-arid rangeland bunchgrasses". It includes the responses of total propagule production, percentage of filled and unfilled seeds, and filled seed-specific mass in response to seed head shading and flag leaf removal in two semi-arid perennial bunchgrasses, crested wheatgrass (Agropyron cristatum) and squirreltail wild rye (Elymus elemoides). Seasonal volumetric soil moisture data is also provided.
README: Data for: Variation in the role of the flag leaf in the reproductive effort of semi-arid rangeland bunchgrasses
https://doi.org/10.5061/dryad.h44j0zptg
This dataset contains the results of a field study examining the contributions of seed head and flag leaf photosynthesis to the reproductive effort of two arid-land perennial bunchgrasses. This was attained by removing flag leaves at two different periods over the reproductive period (before and after fertilization), as well as shading post-fertilized seed heads with mylar sheaths. Reproductive effort metrics include total propagule production (filled and unfilled seeds), percent filled seeds, as well as seed head average filled seed mass and filled seed specific mass (mass per unit surface area).
Description of the data and file structure
Column heading | Explanation | Units or designators |
---|---|---|
SPP | Species | AGCR = Crested wheatgrass |
ELEL = Squirreltail wild rye | ||
Plant | Plant ID# | |
Culm | Culm ID | A, B, C, or D |
Flag | Flag leaf removal treatment | Control = unclipped |
Pre = clipped, pre-anthesis | ||
Post = clipped post anthesis | ||
HeadShade | Seed head shading treatment | Control = unshaded |
Bag = enclosed in shading sheath | ||
TotProp | Total propagules | Empty + filled seeds per culm |
FillNum | Number of filled seeds | Filled seeds per culm |
FillMassTot | Mass of all filled seeds | mg |
PerFill | Percentage filled seeds | |
FillAvePA | Average filled seed projected area | square cm |
FillAveMass | Average filled seed mass | mg |
FillAveSSM | Average filled seed specific mass | mg per square cm |
VSMAve | Average volumetric soil moisture | mol per mol |
Sharing/Access information
You may contact Erik Hamerlynck at erik.hamerlynck@usda.gov
Code/Software
NA
Methods
Plants were randomly assigned into one of six flag leaf clipping/seed-head shading treatments: 1) flag leaves intact and seed-heads unshaded throughout the study (referred to hereafter as control plants), 2) flag leaves intact with post-anthesis seed-head shading, 3) pre-anthesis clipping flag without seed-head shading, 4) pre-anthesis clipping with post-anthesis seed-head shading, 5) post-anthesis clipping flag leaf without seed-head shading, and 6) post-anthesis clipping with seed-head shading. Flag leaves were clipped at the leaf collar sheathing the culm, and seed-head shading was provided by enclosing the post-anthesis seedhead in a mylar sheath. We tried to sample from 5 culms per plant, if at all possible, though culm breakage did occur; only culms that remained intact through the entire study period were used for our statistical analyses. As crested wheatgrass and squirreltail have distinct seasonal reproductive phenologies, these treatments were initiated at different dates throughout the study period, as noted in the supplementary metadata (S1). Starting June 2, weekly volumetric soil moisture (mol3 mol-3) across 10 cm rooting depths adjacent to each sampled plant.
Entire seed heads were harvested after seed filling was completed in control plants of either species. Seed heads were disarticulated, and visually separated into filled and unfilled seed fractions on a light table. The number of propagules in each fraction was counted, weighed on a microbalance to the nearest 0.001 mg, then scanned at 800 dpi resolution on a flat-bed scanner calibrated for use with WinRhizo image analysis software (Regent Software, Quebec, Canada) to determine the projected surface area (cm2) of each fraction. These data provided the total propagule number (empty + filled seeds), the proportion of filled seeds (filled seed/total propagules), aggregate individual filled seed area (total projected area/number), seed mass (total mass/number), and seed-specific mass (total area/total mass; mg cm-2).