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Publication #HS1237

University of Florida Potato Variety Trials Spotlight: ‘Elkton’1

Lincoln Zotarelli, Douglas Gergela, Kathleen Haynes, and Dana Fourman2

General Comments

‘Elkton’ is a white-flesh potato variety suitable for chipping directly from the field (Figures 1 and 2). ‘Elkton’ was selected from the USDA-ARS breeding program in Beltsville, Maryland, by Dr. Haynes in 1997. In 2003, seed of ‘Elkton’ was made available for field evaluation under Florida growing conditions. In 19 trials conducted between 2003 and 2012, ‘Elkton’ yielded 111% in comparison with ‘Atlantic’ (Table 1). In these trials, ‘Elkton’ demonstrated resistance to internal heat necrosis and hollow heart, which are common tuber physiological disorders under high-temperature growing conditions.

Figure 1. 

Typical tuber set and internal flesh color of 'Elkton'.


Credit:

Dana Fourman


[Click thumbnail to enlarge.]

Figure 2. 

‘Elkton’ plants during flowering stage.


Credit:

Dana Fourman


[Click thumbnail to enlarge.]

General Characteristics

‘Elkton’ has white flesh with netted light tan skin. Tubers are round to oval and medium-thick with intermediate eye depth (Figure 1). The variety has good yield potential and specific gravity slightly lower than ‘Atlantic’ (Tables 1, 2, and 3).

Season Length and Growth

The time from planting to harvest is approximately 95–105 days, depending on growing conditions during the season. Tuber size should be checked regularly late in the season. ‘Elkton’ typically shows slower initial growth compared to ‘Atlantic’ planted at the same time; however, during vegetative development ‘Elkton’ shows similar plant size to ‘Atlantic.’

Fertilization

University of Florida trial plots were fertilized with 200 lb/acre of N, with 50 lb/acre of N (granular) incorporated into the beds prior to planting, followed by two split side-dress fertilizer applications of 75 lb/acre of N each at emergence and at tuber initiation.

Planting

A seed piece of 2 1/2 to 3 oz is desired for planting. Plant spacing should be 5 to 8 inches in-row with 36 to 40 inches between rows. Excessive soil moisture late in the season will degrade lenticel appearance.

Diseases and Weed Control

‘Elkton’ appears to be moderately resistant to early blight and verticilium wilt, but the latter still needs confirmation. ‘Elkton’ has shown moderate susceptibility to both foliar and tuber late blight. ‘Elkton’ is moderately susceptible to powdery scab, virus Y and virus S. A standard Extension-recommended disease and weed control program is described in EDIS publication CV131 Potato Production (part of the Vegetable Production Handbook for Florida).

Seed Source

USDA/ARS applied for Plant Variety Protection for ‘Elkton’ with licensing to SeedPro Inc., Crystal, Maine.

Tables

Table 1. 

Summary of production statistics and specific gravity of ‘Elkton’, a chipping potato variety grown at the UF/IFAS research and demonstration farm in Hastings, Florida.

Year

Total Yield

Marketable Yield

% of Atlantic

Size Class

   
       

Distribution by Class %

Range %

 
 

(cwt/ac)

(cwt/ac)

 

C

B

A1

A2

A3

A4

A1 to A3

Culls

Specific Gravity

2004

416.4

369.0

101

5.7

5.4

48.8

32.8

7.2

0.2

88.7

0.9

1.079

2005

415.8

356.2

113

0.9

11.8

54.7

24.2

8.4

0.0

87.3

2.0

1.079

2006

500.5

448.4

121

0.9

6.0

71.0

20.5

1.6

0.0

93.1

3.8

1.087

2007

436.1

396.2

120

0.9

5.8

54.4

23.3

15.2

0.3

92.9

2.4

1.076

2008

469.3

415.3

144

1.5

8.8

62.0

20.0

7.7

0.0

89.8

1.8

1.083

2009

456.0

343.7

120

1.2

7.5

52.2

23.3

14.9

0.9

90.3

7.2

1.061

2010

388.4

232.7

83

4.3

33.5

59.6

2.1

0.5

0.0

62.2

4.6

1.068

2011

332.5

281.2

110

2.3

9.8

62.6

18.2

7.1

0.0

87.9

4.1

1.075

2012

399.4

360.8

90

0.7

3.6

31.6

26.7

34.5

2.8

92.9

3.4

1.083

Average

423.8

355.9

111%

2.0

10.2

55.2

21.2

10.8

0.5

87.2

3.4

1.077

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

2Size classes: C = 0.5 to 1.5 inches, B = 1.5 to 1.9 inches, A1 = 1.9 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])

Table 2. 

Florida rating codes for potato tuber characteristics.1

Tuber Characteristics

 

Rating

Vine

Internal

Skin

Skin

Tuber

Eye

Overall

Code

Maturity

Flesh Color

Color

Texture

Shape

Depth

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 Based on the standard NE1231 rating codes for plant and tuber characteristics.

Table 3. 

Vine maturity, tuber characteristics, and internal tuber defects of ‘Elkton’, a chipping potato variety grown at the UF/IFAS research and demonstration farm in Hastings, Florida.

   

Vine Maturity1

 

Tuber Characteristics (Ratings)

 

Internal Defects %

Year

 

(vine kill)

 

IFC

SC

ST

TS

ED

APP

 

HH

BR

CRS

IHN

2003

 

5.9

 

1.8

5.8

4.8

3.5

6.8

6.2

 

0.0

0.0

0.0

0.0

2004

 

6.3

 

1.2

6.3

5.0

3.6

7.2

5.4

 

0.0

0.0

8.8

2.1

2005

 

n/a

 

1.0

5.0

4.5

4.5

6.5

5.5

 

0.0

0.0

0.0

0.0

2006

 

7.5

 

1.5

6.8

5.5

3.5

7.0

7.2

 

0.0

0.0

0.0

0.0

2007

 

5.8

 

1.7

6.2

4.9

3.0

6.9

6.3

 

0.0

0.0

0.0

0.3

2008

 

5.5

 

1.8

5.7

5.3

3.7

5.3

5.7

 

0.0

0.0

0.0

0.0

2009

 

6.9

 

1.0

6.0

5.0

4.0

6.0

6.0

 

1.3

0.0

0.0

1.3

2010

 

4.4

 

1.5

6.0

5.0

3.5

5.5

6.2

 

0.0

0.0

2.0

1.3

2011

 

5.5

 

2.0

6.0

5.0

3.0

5.0

7.0

 

0.0

0.0

0.0

0.0

2012

 

6.0

 

1.5

6.0

5.0

3.6

6.3

6.2

 

0.1

0.0

1.2

0.5

2013

 

5.9

 

1.8

5.8

4.8

3.5

6.8

6.2

 

0.0

0.0

0.0

0.0

Average

 

6.0

 

1.5

6.0

5.0

3.6

6.3

6.2

 

0.1

0.0

1.1

0.5

1See rating system outlined in Florida Rating Code Table (Table 3).

2Percent tuber defects. HH=hollow heart, BR=brown rot, CRS=corky ring spot, IHN=internal heat necrosis.

n/a = not available

Footnotes

1.

This document is HS1237, one of a series of the Horticultural Sciences Department, UF/IFAS Extension. Original publication date April 2014. Reviewed March 2017. Visit the EDIS website at http://edis.ifas.ufl.edu.

2.

Lincoln Zotarelli, assistant professor, Horticultural Sciences Department; Douglas Gergela, former Research Coordinator of Florida Partnership for Water, Agriculture & Community Sustainability at Hastings; Kathleen Haynes, Genetic Improvement of Fruits and Vegetables Laboratory, USDA-ARS, Beltsville, MD; and Dana Fourman, biological scientist, Horticultural Sciences Department and Florida Partnership for Water, Agriculture & Community Sustainability at Hastings; 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.