• Selection for shade tolerance through the use of a photoselective filter and neutral density shade cloth in a greenhouse is highly

effective, and can be used to screen a large amount of germplasm in a small semi-controlled space within a relatively short

timeframe.

• Using control plants grown under full sun to compare to shade grown plants can help to prevent overlooking shade tolerant plants

with poor turf quality, but still grow similar to plants in full sun conditions.

• These data indicate that HDF’s posses the least amount of variability for shade tolerance, and among the fine fescues, HDF’s

display the least shade tolerant phenotypes overall. STR’s display a large degree of variation for shade tolerance, but many STR’s

exhibit typical shade avoidance symptoms and may not provide a dense, non-etiolated turf.

• CHF’s genotypes display the most amount of shade tolerance among the fine fescues, and CHF’s display a moderate degree of

variability for shade tolerance.

• Conclusions on SLR and SHF cannot be drawn due to the limited sample size.

• Uncaptured variation for shade tolerance exists in fine fescues, and this can be utilized by turfgrass breeders.

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CHF ‘Radar’

CHF ‘PPG-FRC 113’

Evaluating variation in shade tolerance among fine fescue species Dominic P. Petrella and Eric Watkins

Department of Horticultural Science, University of Minnesota, St Paul, MN

Introduction

Material and Methods

• Fine fescue entries from the 2014 NTEP trials (plus standard varieties) were evaluated as individual plants (distinct genotypes) in a

greenhouse in St. Paul MN either under full sun (control) or under combined qualitative/quantitative shade.

• Shade was applied using a combination of a plastic photoselective filter producing a red to far-red ratio of 0.68, and a black shade

cloth that reduced light intensity by 70% .

• Temperature under the shade was on average 0.5 ˚C cooler during the day and 1 ˚C warmer at night compared to full sun.

• A total of 45 entries were evaluated: 10 Chewings fescues (CHF; Festuca rubra ssp. commutata), 14 hard fescues (HDF; Festuca

rubra ssp. brevipila), 16 strong creeping red fescues (STR; Festuca rubra ssp. rubra), 3 slender creeping red fescues (SLR; Festuca

rubra ssp. litoralis), and 2 sheep fescues (SHF; Festuca ovina).

• 5 different genotypes were seeded in 2.5 x 12 cm Conetainers® using soilless media (Sungro® Metro-Mix) on 6/22/17 and 6/14/18.

• Plants were watered to avoid drought and were fertilized with a full nutrient solution containing 200 PPM nitrogen bi-weekly.

• Plants were trimmed to 3 cm bi-weekly following data collection for plant height and tiller number.

Data collection and analysis:

• Plant height and tiller number were measured every 14 d starting 1 month post seeding through 3 months post seeding.

• Data for the ratio of height:tiller number were analyzed. Values ≥ 1 indicate short/dense plants and values ≤ 1 indicate tall/thin plants.

• 3 months post seeding, tissue was harvested for chlorophyll analyses, specific leaf area determination, and biomass analysis.

• Data from full sun plants were used for % of control analysis to determine how similar shade grown plants were to those in full sun.

• Data were analyzed using JMP v. 14.0, and means were compared using Hsu’s multiple comparison with the best (MCB).

• All data collected were used for Principle Component Analysis (PCA) to evaluate relatedness for shade tolerance among fine fescues.

(SAS 9.4 and PROC PRINCOMP).

• Tolerance to shade is a desired trait for cool-season turfgrasses, but improvement in shade tolerance has been challenging.

• Shade tolerant turfgrasses, when grown under quantitative and qualitative shade, should exhibit negligible etiolation, less chlorosis,

and efficient carbohydrate partitioning, while maintaining normal amounts of tillering – therefore growing similar to full sun plants.

• Selection for shade tolerance in the field can be difficult due to large amounts of variation in shade intensity and the duration.

• The fine fescue (Festuca ssp.) turfgrasses are shade tolerant turfgrasses; however, there has been little investigation into the variability

for shade tolerance within and among this turfgrass group.

• Objective: To evaluate the use of a greenhouse-based approach for selecting of improved shade tolerance among the fine fescues.

Results

Conclusions

Raw data only % Full sun control data only Raw data and % full sun data

2017 -

18 m

orp

ho

log

ical

data

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CHF ‘DLFPS-FRC/3057’

HDF ‘DLFPS-FRC/3060’

HDF ‘Reliant IV’

CHF ‘RAD-FC44’

STR ‘Marvel’

Table 1: Results from 9/8/2017 experimental data. Hsu’s MCB results are presented for height:tiller ratio data

only. Top performing entries are labeled green and the bottom performing entries are labeled red. ¶ indicates

Hsu’s best, and ‡ indicates Hsu’s worst.

Fig. 1: Select photos of fine fescue entries and additional

turfgrass species tested under shade. Plants were trimmed prior

to photography, and these images should not be used to judge

etiolation.

Fig. 2: PCA analysis from 2017 and/or 2018 data. Panels A-D include plant height, tiller number, height:tiller ratio, total chlorophyll, chlorophyll a:b, and

biomass as factors. Panels D-F contain height, tiller number, and height:tiller ratio as factors. Panels A and D only use raw data as factors, B and E only use

% full sun control data as factors, and Panels C and F use both raw and % full sun control data as factors.

DFE

Acknowledgements: This project was supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, Specialty Crops Research

Initiative under award number 2017-51181-27222 and the Minnesota State Agricultural Experiment Station Project no. 21-051

• Number of tillers: Similar to height, STR’s

were variable for tillering.

• Most HDF’s were not different than the best or

the worst, but most HDF entries had very few

tillers.

• CHF entries were among the most dense, and

the higher density of the CHF varieties greatly

improved their visual appearance, even if

some were more etiolated (Fig. 1).

• Overall height: Many STR entries displayed typical shade avoidance symptoms (SAS), but STR response was variable.

• HDF entries had a large portion of shorter plants near the end of 2017, but these HDF entries had some of the lowest biomass.

Indicating their lack of growth and shade intolerance.

• CHF entries represented some of the shortest genotypes, were relatively more similar to full sun plants, and these entries produced

moderate amounts of biomass, indicating their improved shade tolerance.

HDF ‘PPG-FL 106’

SLR ‘BAR FRT 5002

All 2

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CHF HDF SHF SLR STR

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CBA

Improved stance in shade Poor stance in shade

HDF ‘DLFPS-PL/3060’

HDF ‘PST-4BND’

PPG-FRR 111’

• Overall height: Similar to 2017, CHF’s genotypes were

among the shortest entries, and STR’s were among the

tallest – showing strong shade avoidance symptoms.

• HDF’s were relatively taller than what was observed in

2017, and the increased growth here may suggest less

shade intolerance compared to 2017.

2018

• Number of tillers: Similar to 2017, CHF entries were

the most dense, and many CHF entries were very

similar to full sun plants.

• STR’s entries exhibited highly variable data for tiller

number.

• HDF’s entries had the least amount of tillers, and

results were more extreme compared to 2017.

However, HDF ‘DLFPS-FRC/3060’, a top performer

from 2017, had the largest number of tillers among

HDF entries.

• Height:tiller ratio: CHF ‘DLFPS-FRC/3057’ on

average exhibited the most improved stance in 2018,

and was the only entry that had a height:tiller ratio ≤ 1.

This entry also had the most similar stance to full sun

plants for 2017 and 2018 data.

• CHF entries were again among the best, displaying

shorter and more dense phenotypes.

• HDF’s were among the worst for the height:tiller ratio,

but showed improvement from 2017.

• STR’s were again highly variable, but performed much

better than HDF’s.

Height:tiller ratio Overall height Tillers Biomass

Species Entry

% Full

sun

control

Avg.

ratio

% Full

sun

control

Avg.

height

(cm)

% Full

sun

control

Avg.

tillers

% Full

sun

control

Biomass

(mg)

CHF BAR 6FR 126 1354.6 4.1 144.2 12.4 12.4 3.6 12.3 8.4

CHF BAR VV-VP3-CT 1288.3 3.7 192.5 15.4 16.9 4.8 41.7 33.0

CHF Cascade 2596.4 11.8 136.2 15.8 6.9 1.8 13.2 13.1

CHF DLF-FRC 3338 1947.1 6.2 151.2 13.0 10.9 3.0 21.9 17.2

CHF DLFPS-FRC/3057 1063.9 3.5 134.0 13.4 16.7 5.0 25.9 17.9

CHF PPG-FRC 113 781.5 2.4¶ 117.4 10.8¶ 16.0 4.8 35.4 24.1

CHF PPG-FRC 114 934.9 3.8 141.3 13.0 15.0 4.0 22.7 16.3

CHF Radar 2542.4 7.6 167.4 14.4 17.9 5.2 42.1 30.9

CHF RAD-FC32 1598.0 5.6 145.8 14.0 9.8 2.8 19.5 14.2

CHF RAD-FC44 804.6 7.1 147.1 15.0 12.8 2.8 15.0 10.3

HDF 7H7 1409.6 4.4 151.3 11.8 10.4 2.8 19.6 16.8

HDF Beacon 1721.8 7.4 166.7 16.0 9.8 2.4 20.3 20.2

HDF DLFPS-FL/3066 2256.0 8.7 134.8 12.4 7.0 1.8 9.3 10.2

HDF DLFPS-FRC/3060 1070.7 3.4 170.7 14.0 19.1 5.0 35.7 30.3

HDF DLFPS-PL/3060 2840.9 8.3 165.9 14.6 7.3 2.2 8.9 10.6

HDF Minimus 2972.2 9.5 154.3 14.2 8.9 2.6 10.0 11.7

HDF MNHD-14 2387.9 8.8 160.5 13.8 8.2 2.0 15.7 17.0

HDF Nanook 2413.7 14.2 116.4 14.2 4.5¶ 1¶ 2.7¶ 2.8¶

HDF PPG-FL 106 1847.4 6.9 187.8 15.4 9.9 2.4 21.9 19.2

HDF PST-4BND 1365.4 9.5 125.0 14.8 8.6 1.8 3.7 4.6

HDF Reliant IV 2184.1 12.9 115.8 16.5 6.8 1.5 7.4 7.3

HDF Spartan II 3837.3‡ 16.4‡ 197.9 19.0 5.1 1.2 4.5 5.2

HDF Sword 1738.2 11.6 164.9 15.5 8.1 2.0 3.9 4.7

HDF TH456 2609.1 7.7 168.2 14.8 8.7 2.6 18.3 21.2

SHF Marco Polo 1245.7 7.1 137.9 16.0 11.4 2.6 7.6 6.7

SHF Quatro 1840.4 6.1 156.8 13.8 10.0 2.8 11.6 10.9

SLR BAR FRT 5002 607.1¶ 4.0 122.6 13.0 24.4 4.4 8.7 7.4

SLR PPG-FRT 101 1504.3 6.6 187.5 18.0 12.0 2.8 21.0 22.6

SLR Seabreeze GT 1652.8 9.7 158.2 17.4 9.2 2.0 12.3 10.3

STR 7C34 2318.4 8.9 172.3 16.2 13.1 3.6 38.4 28.2

STR Boreal 1454.8 11.0 189.7 22.0‡ 28.9‡ 5.2‡ 36.1 30.0

STR C14-OS3 888.0 3.0 148.8 12.8 17.4 4.6 42.9‡ 36.1‡

STR Chantilly 897.0 4.6 172.9 16.6 17.1 4.0 30.8 25.9

STR DLFPS-FRR/3068 1873.5 7.6 175.0 16.8 14.5 3.6 27.4 22.3

STR DLFPS-FRR/3069 2328.8 10.5 206.4‡ 17.8 10.8 2.3 28.0 23.0

STR Kent 1021.1 6.7 145.6 16.6 18.4 3.6 35.9 26.0

STR Marvel 2054.8 15.9 192.5 20.4 9.1 1.6 13.1 8.2

STR Navigator II 1363.3 9.3 147.5 17.4 17.1 3.6 34.4 28.6

STR PPG-FRR 111 2091.7 7.8 155.8 13.4 10.1 2.4 10.7 8.8

STR PST-4BEN 994.7 4.4 164.9 15.5 17.0 3.8 24.1 17.5

STR PST-4DR4 1322.6 4.4 160.0 14.4 16.2 4.4 25.0 22.1

STR PST-4ED4 647.6 3.9 113.8¶ 13.2 16.9 4.2 35.0 25.7

STR PST-4RUE 1177.4 7.7 165.3 16.2 18.5 3.0 8.8 8.7

STR RAD-FR33R 1905.9 6.9 149.0 14.6 9.4 2.6 11.6 7.7

STR RAD-FR47 1232.9 7.7 149.1 15.8 12.4 2.4 7.8 5.5

Height:tiller ratio Overall height Tillers

Species Entry

% Full

sun

control

Avg.

ratio

% Full

sun

control

Avg. height

(cm)

% Full

sun

control

Avg.

tillers

CHF BAR 6FR 126 335.1 2.1 110.7 13.4 39.8 9.8

CHF BAR VV-VP3-CT 465.7 3.0 107.4 14.5 24.2 5.8

CHF Cascade 518.5 3.7 114.2 16.9 18.2 5.2

CHF DLF-FRC 3338 330.6 2.3 101.6 12.7 43.0 9.2

CHF DLFPS-FRC/3057 118.9¶ 0.7¶ 73.9 9.9¶ 54.4 16.2‡

CHF PPG-FRC 113 415.5 2.0 129.0 16.0 36.6 9.8

CHF PPG-FRC 114 530.5 3.0 90.3 12.1 30.7 7.8

CHF Radar 167.1 1.9 99.8 13.1 68.9‡ 13.6

CHF RAD-FC32 514.6 3.8 109.9 15.5 23.4 5.0

CHF RAD-FC44 528.0 4.2 131.2 16.4 26.1 4.8

HDF 7H7 1389.7 6.5 122.6 15.2 11.4 3.4

HDF Beacon 1417.3 5.8 134.8 17.1 9.0 3.3

HDF DLFPS-FL/3066 1117.0 4.8 131.7 16.2 11.3 3.4

HDF DLFPS-FRC/3060 636.1 2.4 129.0 12.9 30.1 8.2

HDF DLFPS-PL/3060 1324.1 6.5 108.3 15.4 12.0 3.8

HDF Minimus 1950.8 7.0 130.5 15.4 8.7 3.2

HDF MNHD-14 1085.2 4.7 99.2 12.5 9.2 2.8

HDF Nanook 1518.4 8.6 104.7 15.5 7.1 2.0

HDF PPG-FL 106 1331.2 5.1 135.9 15.6 11.2 3.5

HDF PST-4BND 896.5 5.4 124.4 15.8 15.7 3.4

HDF Reliant IV 2866.7‡ 14.8‡ 166.7‡ 19.0 5.6¶ 1.6¶

HDF Spartan II 1657.5 9.7 141.4 18.1 10.0 2.4

HDF Sword 1917.5 9.0 118.3 14.2 7.5 2.0

HDF TH456 980.4 4.6 163.7 16.7 13.6 4.6

SHF Marco Polo 1069.5 8.7 131.2 18.1 13.3 2.8

SHF Quatro 1422.2 7.7 123.7 16.7 8.4 2.8

SLR BAR FRT 5002 371.9 4.9 92.9 15.6 24.0 3.6

SLR PPG-FRT 101 811.6 3.9 109.8 16.8 18.6 6.0

SLR Seabreeze GT 208.3 2.6 109.1 15.0 40.0 6.0

STR 7C34 574.5 4.2 121.3 19.4 22.2 5.2

STR Boreal 1163.1 10.3 112.9 18.4 13.4 3.0

STR C14-OS3 609.8 3.2 118.8 13.9 19.2 4.6

STR Chantilly 1235.5 6.0 122.8 15.1 26.8 8.4

STR DLFPS-FRR/3068 556.1 2.6 155.6 16.8 24.2 7.4

STR DLFPS-FRR/3069 595.0 3.3 136.5 17.8 28.9 7.0

STR Kent 467.9 4.6 114.0 17.9 23.7 4.6

STR Marvel 171.1 2.7 68.3¶ 14.0 40.8 5.8

STR Navigator II 657.3 5.5 133.1 20.3‡ 21.3 4.6

STR PPG-FRR 111 553.0 4.2 132.2 18.9 23.1 5.0

STR PST-4BEN 683.8 5.2 106.7 17.4 19.7 5.2

STR PST-4DR4 278.8 2.2 104.2 17.3 40.9 10.4

STR PST-4ED4 403.7 2.2 110.7 16.6 29.8 8.4

STR PST-4RUE 372.1 2.8 105.4 15.5 25.0 7.8

STR RAD-FR33R 516.5 3.5 110.4 15.9 28.1 6.8

STR RAD-FR47 478.2 4.6 97.1 16.9 28.3 5.2

• Height:tiller ratio: HDF ‘Spartan II’ exhibited poor stance – tall and not dense, and was also the most different from full sun plants.

CHF ‘PPG-FRC 113’ plants exhibited the most improved stance – short and dense, and was more similar to full sun plants (Table 1;

Fig. 1).

• HDF’s had the most entries that displayed a poor stance that were very different from full sun.

• CHF’s and STR’s had a large amount of diversity for the height:tiller ratio, but CHF entries mostly displayed improved stance (Fig. 1).

• Principle component analysis (PCA) was used to

better evaluate relatedness among the fine fescue

entries tested (Fig. 2). Results showed little clustering

by species, and clusters mostly overlapped.

• When using all of the data from 2017 (Fig. 2A-C;

including chlorophyll parameters, specific leaf area, and

biomass) it was apparent that HDF’s clustered closer

together than both STR and CHF, but species clusters

still mostly overlapped.

• Clustering improved when % of full sun control data

was included.

• 2017 and 2018 data for height, tiller number, and the height:tiller ratio were analyzed together and clusters tightened (Fig. 2D-

F), and the same trends can be seen using 2017-2018 data.

• Overall, tighter HDF clustering suggests decreased variability for shade tolerance, while the increased spread of CHF and STR

clusters indicates a greater degree of variability for shade tolerance.

CHF ‘Cascade’STR ‘PST-4DR4’

STR ‘PST-4ED4’ HDF ‘Spartan II’

Poa annua ‘DW 184’ Lolium perenne ‘Accent II’

2017

Table 2: Results from 8/27/2018 experimental data. Hsu’s MCB results are presented for

height:tiller ratio data only. Top performing entries are labeled green and the bottom

performing entries are labeled red. ¶ indicates Hsu’s best, and ‡ indicates Hsu’s worst.