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Publication #HS1298

University of Florida Potato Variety Trials Spotlight: 'Harley Blackwell'1

Mario H. M. L. Andrade, Rodrick Z. Mwatuwa, Christian T. Christensen, Pam Solano, Kathleen G. Haynes, and Lincoln Zotarelli2

Introduction

There are several potato varieties available in the market today. Most of them have been bred or developed in production regions other than Florida. The University of Florida Potato Variety Evaluation Program screens new germplasm from public and private breeding programs and identifies the most promising cultivars for commercial potential considering broad adaptability to Florida climate and conditions and market purpose: processing, fresh-market and specialty-type varieties. Over the years, the UF/IFAS Potato Variety Program has become an important reference to vegetable growers, seed producers, processors, crop insurance agencies, and brokers looking for alternative potato varieties to explore different markets, improved characteristics, and yield. This UF/Potato Variety Trials Spotlight presents a summary of the field evaluation of tuber yield and quality performance of the potato variety ‘Harley Blackwell’ cultivated in Florida.

General Comments

‘Harley Blackwell’ is a potato variety that is commonly grown for the potato chip market. It was selected from the progeny of a cross between B0155-24 and B9935-8 and tested under the pedigree B0564-8. It was released and named jointly by the Agricultural Research Service, the United States Department of Agriculture, the Agricultural Research Service of North Carolina, the Agricultural Experiment Stations of Virginia, New Jersey, Pennsylvania, Florida, and New York, and the Maine Agricultural and Forest Experiment Station in 2000. Tuber production and quality results provided in this spotlight are summarized from various variety trials conducted at the UF/IFAS Hastings Agricultural Extension Center between 1998 and 2019.

General Characteristics

‘Harley Blackwell’ tubers are mostly round with a white flesh color (Figure 1). According to Florida’s rating codes for potato tuber characteristics (Table 1), the tubers have a good appearance with buff skin color, slightly netted skin texture, and intermediate to shallow eye depth (Table 3). ‘Harley Blackwell’ demonstrates high yield potential under Florida production conditions (Tables 2 and 3). On average, marketable yield is 265 cwt/acre with 83% of the tubers produced found between A1 and A3 tuber size classification and low incidence of internal defects like internal heat necrosis. The variety has a medium to high specific gravity of 1.074 (Table 2).

Figure 1. 

Typical tuber and internal flesh color of ‘Harley Blackwell’ potato variety.


Credit:

Kathleen Haynes, UF/IFAS


[Click thumbnail to enlarge.]

Diseases

‘Harley Blackwell’ is resistant to race A of the golden nematode (Globodera rostochiensis). It is susceptible to Verticillium wilt (Verticillium albo-atrum and Verticillium dahliae) and late blight (Phytophthora infestans). It is moderately susceptible to early blight (Alternaria solani), with intermediate resistance to common scab (Streptomyces scabies), and some tolerance to powdery scab (Spongospora subterranea f. sp. subterranea). The standard UF/IFAS Extension recommended disease and weed control program described under Potato Production (Chapter 14 of the Vegetable Production Handbook for Florida, http://edis.ifas.ufl.edu/cv131) should be followed.

Season Length and Growth

‘Harley Blackwell’ is an early- to medium-maturing variety. Season length was 100 days on average from planting to harvest. This depended on weather conditions during the growing season. Late in the season, tuber size should be closely monitored to harvest tubers with marketable size. Soil moisture should be managed late in the season to avoid high soil moisture conditions that cause enlarged lenticels, which are sites of entry for decay organisms.

Fertilization

UF/IFAS trial plots are normally fertilized with 200 to 230 lb/ac of N. The first application of 100 lb/ac of N (granular) is typically incorporated in the bed 2 to 5 days prior to planting, followed by one or two side-dress fertilizer applications at emergence and/or at tuber initiation. Phosphorus and potassium applications follow the UF/IFAS guidelines described in Liu et al. (2020) and normally range between 45 to 100 lb/ac of P2O5 and 170 to 235 lb/ac of K2O.

Planting

A seed piece of 2½ to 3 oz is recommended for planting. This variety should be planted with 40 inches between rows and 8 inches between plants, at 3 to 4 inches deep. A seed rate of 2,000 to 3,000 lb/acre of seed is expected.

Other Information

For additional information on cultivation and weed and disease management, see the Potato Production chapter of the Vegetable Production Handbook, available at http://edis.ifas.ufl.edu/cv131.

References

Hutchinson, C. M., J. M. White, D. M. Gergela, P. A. Solano, K. G. Haynes, R. Wenrich, and C. S. Lippi. 2003. “Performance of chip processing potato varieties in northeastern Florida.” HortTechnology 13 (4): 706–711. https://doi.org/10.21273/HORTTECH.13.4.0706

Liu, G., E. H. Simonne, K. T. Morgan, G. J. Hochmuth, S. Agehara, and R. Mylavarapu. 2020. Chapter 2. Fertilizer Management for Vegetable Production in Florida. Vegetable Production Handbook for Florida, 2020–2021 Edition. CV296. Gainesville: University of Florida Institute of Food and Agricultural Sciences. http://edis.ifas.ufl.edu/cv296

Navarre, R., and M. Pavek. 2014. The Potato: Botany, Production and Uses. CABI. https://doi.org/10.1079/9781780642802.0000

Sisson, J. A., and G. A. Porter. 2002. “Performance evaluations of potato clones and varieties in the northeastern states—1999.” Maine Agr. For. Expt. Sta., Misc. Publ. 751.

USDA-ARS. 2016. “Naming and Release Of the `Harley Blackwell' Potato Variety.” https://www.ars.usda.gov/Services/Docs.htm?docid=19468. Accessed 2 February 2021.

Zotarelli, L., P. J. Dittmar, P. D. Roberts, J. Desaeger, and B. Wells. 2020. Chapter 14. Potato Production. Vegetable Production Handbook for Florida, 2020–2021 Edition. HS733. Gainesville: University of Florida Institute of Food and Agricultural Sciences. http://edis.ifas.ufl.edu/cv131

Tables

Table 1. 

Florida rating codes for potato vine maturity and tuber characteristics.

Tuber Characteristics1

     

Rating Code

Vine Maturity

Internal Flesh Color

Skin Color

Skin Texture

Tuber Shape

Eye

Depth

Overall Tuber Appearance

1

dead

white

purple

partial russet

round

very deep

very poor

2

+-

cream

red

heavy russet

mostly round

--

--

3

yellow and dying

light yellow

pink

moderate russet

round to

oblong

deep

poor

4

+-

medium yellow

dark brown

light russet

mostly oblong

--

--

5

moderately

senesced

dark yellow

brown

netted

oblong

intermediate

fair

6

+-

pink

tan

slightly netted

oblong to long

--

--

7

starting to

senesce

red

buff

moderately

smooth

mostly long

shallow

good

8

+-

blue

white

smooth

long

--

--

9

green and

vigorous

purple

cream

very smooth

cylindrical

very shallow

excellent

1 Adapted from Hutchinson et al. (2003) and Sisson and Porter (2002)

Table 2. 

Summary of production statistics and specific gravity of ‘Harley Blackwell’ grown at the UF/IFAS Hastings Agricultural Extension Center, Hastings, FL from 1998 to 2019, excluding 2001.

Year

Total Yield (cwt/ac)

Marketable Yield (cwt/ac)¹

% of

STD

Standard

Size Class (Distribution by Class %)²

Range %

Specific Gravity

C

B

A1

A2

A3

A4

A1 to

A3

% Culls

1998

390

307

84

Atlantic

0

22*

46

25

7

0

79

14

1.072

1999

384

342

97

Atlantic

0

11*

79

10

0

0

89

5

1.065

2000

290

254

73

Atlantic

0

13*

39

30

18

0

88

8

1.073

2002

256

235

83

Atlantic

0

6*

52

35

7

0

94

3

1.076

2003

416

344

86

Atlantic

0

14*

39

30

16

1

85

3

1.075

2004

347

282

86

Atlantic

11

8

51

25

5

0

81

1

1.087

2005

339

290

102

Atlantic

1

13

69

15

2

0

86

0

1.083

2006

401

333

89

Atlantic

1

14

74

10

1

0

84

1

1.087

2007

359

303

82

Atlantic

2

12

65

16

5

0

86

2

1.075

2008

341

279

98

Atlantic

3

14

57

17

11

0

84

3

1.079

2009

356

288

105

Atlantic

2

11

67

12

8

0

87

8

1.066

2010

367

253

93

Atlantic

4

24

65

5

2

0

72

5

1.072

2011

331

278

106

Atlantic

3

11

63

17

6

0

86

3

1.074

2012

363

300

70

Atlantic

2

9

57

16

15

0

88

7

1.074

2013

314

282

110

Atlantic

2

7

59

18

14

0

92

2

1.071

2014

295

192

85

Atlantic

5

25

60

6

4

0

70

7

1.068

2015

279

201

79

Atlantic

3

15

64

10

8

0

82

13

1.067

2016

263

167

61

Atlantic

9

23

56

6

6

0

67

6

1.071

2017

229

144

70

Atlantic

8

18

65

6

3

0

74

16

1.075

2018

311

247

107

Atlantic

5

13

68

8

7

0

82

4

1.076

2019

312

249

75

Atlantic

5

8

28

52

3

0

87

9

1.077

Average

331

265

88

Atlantic

3

14

58

18

7

0

83

6

1.074

¹Marketable yield: Sum of size classes A1 to A3.

²Size classes: C = 0.5 to 1.5 inches, B = 1.5 to 1 7/8 inches, A1 = 1 7/8 to 2.5 inches, A2 = 2.5 to 3.25 inches, A3 = 3.25 to 4 inches, A4 >4 inches; Size distribution by class: Class (wt)/(Total Yield [wt] – culls [wt]) n.a. = not available

* Classification = <1 7/8 inches (C and B included in this classification)

Table 3. 

Vine maturity, tuber characteristics, and internal tuber defects of ‘Harley Blackwell’ potato variety grown at the UF/IFAS Hastings Agricultural Extension Center, Hastings, FL from 1998 to 2019, excluding 2001.

Year

Vine

Maturity

(vine kill)

Tuber Characteristics1

 

Internal Defects2

 

Internal Flesh Color

Skin Color

Skin Texture

Tuber Shape

Eye

Depth

Overall

Appearance

HH

BR

CRS

IHN

1998

0

0

8

7

3

6

7

0

0

0

0

1999

0

0

8

5

2

4

6

0

0

0

0

2000

0

0

6

5

2

6

6

0

0

0

0

2002

2

2

7

6

2

7

7

0

0

0

1

2003

5

1

6

5

2

6

7

12

0

0

0

2004

4

1

7

5

2

7

7

0

0

0

0

2005

6

1

6

5

2

7

7

0

0

0

0

2006

*

1

6

6

3

6

6

0

0

0

0

2007

6

2

6

5

3

5

7

0

0

0

0

2008

5

2

7

5

2

6

7

0

0

0

0

2009

3

1

6

5

3

4

6

1

0

0

0

2010

7

1

6

5

3

6

7

2

0

0

1

2011

3

1

6

5

2

5

7

0

0

11

2

2012

5

2

6

5

3

5

6

1

0

0

1

2013

5

1

6

5

3

4

6

2

0

0

2

2014

2

1

7

5

3

5

7

0

0

0

0

2015

6

1

9

8

2

7

8

0

2

0

0

2016

7

1

6

7

2

7

7

0

0

0

0

2017

7

1

8

5

2

8

7

0

0

0

0

2018

7

1

7

7

2

8

8

0

0

0

0

2019

6

1

6

7

2

7

7

0

0

0

0

Average

4

1

7

6

2

6

7

1

0

1

0

¹See rating system outlined in Florida Rating Code Table (Table 1).

²Percent tuber defects. HH = hollow heart, BR = brown rot, CRS = corky ring spot, IHN = internal heat necrosis. *data not available

Footnotes

1.

This document is HS1298, one of a series of the Horticultural Sciences Department, UF/IFAS Extension. Original publication date May 2017. Revised February 2021. Visit the EDIS website at https://edis.ifas.ufl.edu.

2.

Mario H. M. L. Andrade, research scholar; Rodrick Z. Mwatuwa, research assistant; Christian T. Christensen, regional specialized agent II, director, UF/IFAS Hastings Agricultural Extension Center; Pam Solano, biological scientist; Kathleen G. Haynes, Genetic Improvement of Fruits and Vegetables Laboratory, USDA-ARS, Beltsville, MD; and Lincoln Zotarelli, associate professor; Horticultural Sciences Department, UF/IFAS Extension, Gainesville, FL 32611.


The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other UF/IFAS Extension publications, contact your county's UF/IFAS Extension office.

U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.