DOI: 10.5281/zenodo.10959725
title: The adaptability of barley phenotypes used in whisky distillation to future climate change predictions

description: Raw leaf number, shoot length (cm), root to shoot ratio, total root length (cm) , total root volume (cm3), total root tips and total root surface area data (cm2) and x-ray CT scans for an Msci Environmental Science project.

PS1 = soil drained for 1 day post saturation

PS3 = soil drained for 3 days post saturation

Clay = clay loam soil

Sand = sandy loam soil

Warm = 16 degrees C day temperature and 14 night with 14 hour photoperiod

Cool = 8 degrees C day temperature and 6 night with 14 hour photoperiod

LA = Laureate barley variety

PL = Planet barley variety

 

Methods:

Three abiotic factors were tested in this experiment: Temperature, soil water content, and soil texture. The temperature had 2 treatment levels: 16OC day/14OC night (Summer) and 8OC day/6OC night (Winter) both of which had a 14hr photoperiod. Soil water content had two treatments levels: Drained for 1 day post full saturation of soil (PS1) and drained for 3 days post full saturation of soil (PS3), these represent upper and lower limits for an approximated field capacity. Finally soil texture also had two treatment levels: Clay loam soil and sandy loam soil. Two different malting barley varieties that are used for whisky distillation were used in this experiment: Laureate and Planet.

The abiotic factor treatments combined with the 2 different malting barley varieties gave this experiment a total of 16 treatment levels, each of which was replicated 5 times.

1.1. Soil and seed preparation

Both sandy loam and clay loam soils were sieved using a 2mm fine sieve to remove any rocks and seeds. To prepare the soil columns, 603 grams of soil was mixed with 20ml of water to assist packing, this soil was poured into the columns and compacted to a bulk density of 1.25g/cm3. All the soil columns were fully saturated, then left to drain. Half the columns were weighed 1 day post saturation and the other half 3 days post saturation. The clay loam soil after 1 day had a mean gravimetric water content of 42%, after 3 days it had a mean gravimetric water content of 32%. The sandy loam soil after 1 day had a mean gravimetric water content of 41%, after 3 days it had a mean gravimetric water content of 30%.

Seeds of both barley varieties were germinated before sowing. Before sowing all soil columns were reweighed and watered accordingly. A small hole was made in the soil and the germinated barley seeds were placed in root down, covered with 40g of soil and 10ml of water, then reweighed. Half the soil columns were placed in the summer temperature growth room and the others in the winter temperature growth room, they were all then watered 3 times a week for 25 days.

1.2. Analysis of samples

After 25 days the plants were removed from the growth rooms, 8 samples were examined using X-ray computed tomography (X-ray CT), then all the plants were harvested. The number of leaves and shoot length (cm) of each plant was recorded. 

The soil was washed from the roots of each plant and then each root network was scanned using an Epson Expression 11000XL scanner. These scans were then analysed using winRHIZO version 2014 which categorised roots by diameter and calculated total root length (cm), total root volume (cm3), total root tips and total root surface area (cm2).

The roots and shoots of all plants were dried for 48 hours in an oven at 60°C and then weighed to calculate root to shoot ratio.

1.3. Data analysis

All data analysis was conducted using R studio version 2023.12.1. Analysis of variance (ANOVA) tests were conducted to determine the significance and the interaction of the different abiotic factors on each of the barley growth and root morphology metrics. ANOVA tests were also conducted to determine whether there was any significant genotypic variation in the growth and root morphology metrics. 

VGStudio max version 2023.1 was used to construct root images from X-ray CT scans.