DOI: 10.5061/dryad.dbrv15fcg
title: Predictive ability of hop (Humulus lupulus L.) grown in single hills on plot environments

description: Hop (Humulus lupulus L.) is a perennial, climbing plant species whose
 female strobiles or cones play a critical role in flavoring and bittering
 beer. The species is dioecious and outcrossing, and new cultivars are
 clonally propagated. The breeding timeline from cross to release is
 generally long, averaging between 13 and 15 years. We evaluated the
 predictive ability of various plant spacings and trellis configurations to
 see how predictive early-stage breeding environments were of later stages
 to see if accurate selections could be made earlier in the pipeline. We
 evaluated the performance of seven hop cultivars with varying end uses
 (high alpha, aroma, and dual purpose) in the seedling year in
 high-density, short-trellis plantings (0.46 and 0.61 m apart on a 2.4 m
 trellis), in established, low-density, single-hill nurseries (1.52 and
 21.3 m apart on a 5.4 m trellis) and in plots representative of the
 commercial standard (1.07 m on a 5.4 m trellis). The trial was established
 in a single location in Prosser, WA, U.S., and was conducted for two years
 in 2022 and 2023. The experiment was established as a split-plot design in
 which the main plot factors, spacing, and trellis configurations, were
 randomized according to a randomized complete block design with four
 blocks. A variety of agronomic and cone-related traits were measured,
 including flowering time, percent up a string (vigor) lateral length,
 flowering pattern, harvest date, wet cone yield, dry matter at harvest,
 harvest index, alpha acid, beta acid, hop storage index (HSI), cone area,
 cone length, cone width, perimeter, and openness.
description: Flowering time, vigor, arm length, and flowering pattern were all
 collected by visual observations in the field. The remainder of traits
 were collected at harvest. Hop bines were pulled from the trellis,
 transported to a Wolf 170 hop picker where they were weighed, measured,
 and cones were separated. Ten cones were imaged using the HopBox, and the
 reaminder of the cones were dried and submitted for alpha, beta, and HSI
 measurements according to ASBC methods a local hop lab. The data were
 collected using tablets, and tracked throughout the harvest process using
 thermal printed tags and barcodes. All datasets were compiled using
 Program R. 
description: # Predictive ability of hop (*Humulus lupulus* L.) grown in single hills
 on plot environments
 [https://doi.org/10.5061/dryad.dbrv15fcg](https://doi.org/10.5061/dryad.dbrv15fcg) ## Description of the data and file structure This dataset includes seven different hop (*Humulus lupulus* L.) cultivars evaluated in five different trellis and spacing configurations in Prosser, WA, U.S. in 2022 and 2023. There are a number of phenotypic traits reported, including agronomic traits, as well as cone quality and morphological traits. Missing data are represented with "NA".  ### Files and variables #### File: spacing\_trial\_dat.csv **Description:**  ##### Variables * backbone_merge: the barcode used to identify the plot/plant, starting with the cultivar name, the year, the spacing (in feet), the row number in the field, and in cases of the 3.5 foot spacing (or plot, where there were 7 plants), the hill position, and in cases of all other spacings, an arbitrary 1 (as cultivar and spacings were not repeated within rows). The hill positions were retained in order to evaluate the variation within plots.  * genotype: cultivar name * row: field row number * spacing: distance between the plant and its nearest neighbor (the treatment), in feet * position: position within the field (see backbone_merge description) * year: year of the trial (2022 or 2023) * notes: any notes taken during harvest or otherwise * flowering_time: categorical rating of flowering time modeled after the BBCH scale for hop but more intuitive in the field; in order from least mature to most mature: no burs, burs visible, burs dried up, small cones, full sized cones.  * percent_up_string: a visual estimate of how far up the plant had climbed onto the string, which is fixed to the ground and tied to the top of the trellis. Trellis height varied depending on the treatment (8 ft for 1.5 and 2 ft spacings; 18 feet for the 3.5, 5 and 7 ft spacings).  * arm_length: a visual rating of the length of an average, normal lateral arm, where 0 = no arms, and 5 = 5 feet * flowering_pattern: a visual assessment of flower distribution across the bine * harvest_date: date when the plants were harvested * wet_plant_weight_g_less_string: the weight of the wet plant (two bines per hill, except for the seedlings and unless otherwise noted) prior to picking, used in calculating harvest index. The weight was adjusted to remove the weight of the string, which was estimated by length, weight per unit length, and string type (seedlings in the first year were strung with a lightweight cotton, otherwise coir was used).  * wet_cone_weight_g: the weight of the wet cones after picking * dry_matter_percent: the dry matter for that genotype one the date it was picked, if missing data was present, the mean of the other genotypes was used.  * dry_cone_weight_g: weight of the cones after drying, which was only conducted in the first year due to a high correlation observed between predicted cone yield (wet cone yield adjusted for dry matter).  * hop_box_weight_g: wet weight in grams of the (approximate) 10 cones used in imaging using the HopBox * harvest_index: wet_cone_weight_g divided by wet_plant_weight_g_less_string * UV_AA: alpha acids content as measured by UV-Vis according to to American Society of Brewing Chemists (ASBC) method Hops-6A/12 * UV_BA: beta acids content as measured by UV-Vis according to to American Society of Brewing Chemists (ASBC) method Hops-6A/12 * UV_HSI: hop storage index as measured by UV-Vis according to to American Society of Brewing Chemists (ASBC) method Hops-6A/12 * predicted_dry_cone_weight_g: estimated dry cone weight after adjusting wet cone yield by dry matter percentage at harvest, and assuming a moisture content of 10% after drying  * rep: rep or block, 1-4 * area: cone area, measured in cm2, on average across all cones in the image * length: cone length, measured in cm, on average across all cones in the image * width: cone width, measured in cm, on average across all cones in the image  * perimeter: cone perimeter, measured in cm, on average across all cones in the image  * openness: calculated by dividing the total perimeter of a cone by its length down the median plane, average across all cones within the images * cone_ct: number of cones measured in the image ## Code/software The data can be easily viewed in Microsoft Excel.  ## Access information Other publicly accessible locations of the data: * N/A Data was derived from the following sources: * N/A