Research in the Klamath Basin
20 07 Annual Report
Russet Potato Variety Development, 2007
Brian A. Charlton and Darrin A. Culp1
Introduction
Since its inception in 1985, the Tri-State variety development program has
primarily focused on the development of processing and dual-purpose (processing and
fresh market) russets. During the past decade, Oregon has been the lead state in the
release of nine varieties and is in the process of releasing two additional russets in 2008.
In total, more than 25 new varieties have been released by the Tri-State variety
development program since 1985. Although the development of russet varieties remain
the primary focus, recent efforts have included red-skinned and specialty-type selections.
Many of these selections offer unique skin and/or flesh color combinations along with
enhanced nutritional qualities including elevated antioxidant and Vitamin C content.
Breeding efforts have focused more on improving genetic resistance to various
pests and diseases as a means of lowering production costs. For example, screening for
resistance to foliar and tuber late blight occurs in Corvallis, Oregon as environmental
conditions are conducive to disease development. High insect and disease pressure
occurs in the long growing-season of the Columbia Basin which makes the Hermiston
Agricultural Research & Extension Center (HAREC) an ideal screening location for
potato virus Y (PVY), potato leaf roll virus (PLRV) and associated problems of net
necrosis, early die syndrome, and more recently potato tuber moth (Phthorimaea
operculella (Zeller)). Screening for resistance to various species of nematodes and
related diseases is being accomplished at several locations. The Klamath Basin Research
and Extension Center (KBREC) routinely screen selections for resistance to root-knot
nematode (Meloidogyne chitwoodi and Meloidogyne hapla) and corky ringspot disease
resulting from infection of Tobacco rattle virus which is vectored by stubby-root
(Paratrichodorus spp.) nematodes. Other cooperating sites within the Tri-State area also
work on resistant screening and other production limitations most suited to their
respective location. The overall objective is that future releases will offer genetic
resistance to many economically important pests and diseases which will help reduce
production inputs as these continue to rise in cost.
KBREC participation in the Tri-State evaluation of new russet lines includes the
following: Preliminary Yield Trial 2 (PYT-2), Statewide Russet Trial, and the late-season
Western Regional Russet Trial. In general, selections currently in the PYT-2 trial were
selected two to three years earlier from single-hill selections. Clones advancing from the
PYT-2 trial enter the Statewide Russet trial the following year and may advance after two
1
Assistant Professor and Faculty Research Assistant, respectively, Klamath Basin Research and Extension
Center, Klamath Falls, OR.
Acknowledgements: Partial financial support for this program from the Oregon Potato Commission; the
Cooperative State Research, Extension, and Education Service (CSREES); and the USDA Agricultural
Research Service (ARS) is gratefully recognized.
Reference to a product or company is for specific information only and does not endorse or recommend
that product or company to the exclusion of others that may be suitable.
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Klamath Basin Research and Extension Center
Russet Potato Variety Development, 2007 Page 1
Research in the Klamath Basin
20 07 Annual Report
years of testing to the Tri-State trial. Clones graduating from the Tri-State trial advance
to the Western Regional Russet Trial which also includes material from breeding
programs in Colorado and Texas. Oregon selections remain in the Oregon Statewide
Trial until they complete regional evaluation or are discarded. In most circumstances, a
period of 12 to 15 years is required to release a variety following the actual breeding
cross.
Procedures
Trials were conducted on a Poe fine sandy loam soil at KBREC. The soil has a
pH of 6.8 and an organic matter content of 1.02 percent in the plow layer. The location
was cropped to teff grass hay the previous year, which was treated with roundup during
the fall of 2006 to aid in breakdown of material through the winter. Gypsum was applied
at a rate of 2000 lbs/acre on April 11. Field preparation included discing twice, rototilling once, and moldboard plowing once to break up sod in mid-April 2007. Fumigation
treatments included TeloneTM II (dichloropropene, Dow AgroSciences) at 15 gal/acre
(gpa) and Vapam (sodium methyldithiocarbamate, AMVAC) at 25 gpa on April 26,
2007, followed by several harrowing passes on May 7. Dry pre-plant fertilizer was
broadcasted on May 9 followed by liquid fertilizer applied at bed formation on May 10.
Total pre-plant fertilizer included 165 lb Nitrogen (N), 80 lb Phosphate (P2O5), 100 lb
Potash (K20) and 140 lb Sulfur (S).
Seed for all trials was hand cut to approximately 1.5-2.0 oz/seed piece on May 9,
10 and 11, treated with Tops MZ (thiophamate-methyl, mancozeb, Bayer CropScience),
and suberized for 2 weeks at 550F and approximately 95 percent relative humidity. All
trials (Preliminary (PYT-2) Russet, Statewide Russet, and Regional Russet) were planted
at 9-inch spacing in 36-inch rows with an assisted-feed, 2-row planter on May 23. The
insecticide Admire Pro (imidacloprid, Bayer CropScience) at 5-6 fl. oz. / acre and the
fungicide Quadris (azoxystrobin, Syngenta) at 6-8 fluid oz. / acre were applied in-furrow
over the seed piece.
Planted rows were bedded up and leveled off with a rolling cultivator and drag bar
followed by a pre-emergence application of Dual II Magnum (s-metalachlor, Syngenta) at
1.3 pt./ acre and Prowl H2O (pendimethalin, BASF) at 1.5 pt./ acre on June 12 for
broadleaf and grass weed control. Immediately following application, 0.43 inches of
irrigation was supplied to incorporate the herbicides. Matrix (rimsulfuron, Dupont) was
applied post-emergence at 1 oz. / acre on July 5 and incorporated with 0.25 inches of
irrigation. A total of 19.7 inches of water (irrigation plus rainfall) was applied during the
growing season with sprinklers arranged in a 40- by 48-ft. pattern.
All trials were arranged in a randomized complete block design. The PYT-2
Russet Trial included 2 replications of 20-hill plots. Entries for the PYT-2 Russet Trial
included standard varieties Russet Burbank, Ranger Russet, Shepody, and Russet
Norkotah, and 66 numbered selections. The Statewide Russet Trial had 4 replications of
30-hill plots and included 15 numbered selections in addition to the same standard
varieties as those in the PYT-2 trial. The Western Regional Russet Trial had 4
replications of 30-hill plots. Ranger Russet, Russet Burbank, and Russet Norkotah were
the standard varieties along with 16 numbered selections.
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Klamath Basin Research and Extension Center
Russet Potato Variety Development, 2007 Page 2
Research in the Klamath Basin
20 07 Annual Report
Plant stands were monitored on June13 and 27. Vine vigor was noted on July 25.
On July 26 the fungicide Ridomil Gold Bravo (mefenoxam/chlorothalinil, Syngenta) and
the insecticide Leverage (imidacloprid, cyfluthrin, Bayer CropScience) was applied
aerially. Another application of Ridomil Gold was applied on August 10 at labeled rates.
Plant maturity assessments were done September 6 followed by vine rolling and Reglone
(diquat dibromide, Syngenta) application at 1.5 pt. /acre with a ground sprayer on
September 10.
Tubers were harvested using a one-row digger-bagger on October 5 (Regional
Russet), October 8 (PYT-2 Russet), and October 9 (Statewide Russet). All tubers from
each plot were stored at 550F until grading in early to mid November. Using USDA
potato grade standards, each plot was graded into U.S. No. 1s, No. 2s, B’s (under 4 oz.)
and culls. U.S. No. 1s were separated by weight to 4- to 8-oz, 8- to 12-oz, and over 12-oz
groupings. Sub-samples of approximately 10 lbs from the 8- to 12 oz. fraction were used
to determine specific gravity by the weight-in-air, weight-in-water method. Ten tubers
from the over 12-oz were selected at random and cut lengthwise to determine internal
defects.
External characteristics were noted for each replication. Potatoes were
downgraded to No. 2s or culls if growth cracks, knobs, or misshapen tubers were severe
enough according to USDA grade standards. Yields for U.S. No. 1s were not adjusted to
account for external blemishes such as Rhizoctonia or silver scurf or internal defects such
as hollow heart, brown center, and others.
With exception of the PYT-2 Russet Trial, data collected was analyzed using SAS
for Linear Models 9.1 (SAS Institute Inc.) software. Least significant differences (LSDs)
were calculated based on the student’s t test at the 5 percent probability level. Only a
portion of the data obtained is reported here. Data from all trial locations were
summarized and reports were reviewed by all cooperators on January 3 and 4, 2008 as the
basis for decisions on disposition of trial entries.
Results and Discussion
Preliminary Yield Trial
A partial summary of yield characteristics of the clones selected for further
evaluation based on performance at KBREC is presented in Table 1. Eleven numbered
selections out of 66 were retained for further evaluation. Ideally, clones retained must
perform well at all locations; however, vast differences in climate, insect and disease
pressures, and other production scenarios among the testing locations prevent such
performance uniformity. Therefore, several selections are retained because of superior
performance at one location. In general, total yield of retained selections were slightly
lower than those of the standard varieties; however, yields of U.S. No. 1’s were generally
higher. Specific gravities were exceptionally high in 2007 compared to previous years
with several selections exceeding the 1.088 cap at which processing contracts begin to
assess penalties. In general, the ‘OR’ clones and POR05V016-2 were retained for
genetic resistances to various pests and diseases. These selections had poorer tuber
appearance than the standard entries and would likely find difficulty in meeting fresh
market appearance standards with the exception of POR05V016-2 which possessed very
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Klamath Basin Research and Extension Center
Russet Potato Variety Development, 2007 Page 3
Research in the Klamath Basin
20 07 Annual Report
uniform tuber appearance. AO01114-4, AO02060-3, and AO03003-3 performed
exceptionally well at KBREC and had excellent tuber appearance.
Statewide Yield Trial
All entries in this trial achieved excellent stands (Table 2) Most of the numbered
selections were similar in maturity to Russet Burbank and Ranger Russet with all
selections being later in maturity compared to Russet Norkotah. Hollow heart was not a
problem in 2007 compared to previous years; however, Russet Norkotah and AO96141-3
exhibited 15 and 13 percent, respectively. Although, excessive tuber size in these entries
undoubtedly skewed these values to some degree. Corky ringspot was problematic in
Ranger Russet, AO96164-1, AO96305-3, and AO98286-4. Three of the top yielding
selections (AO96365-2, AO98282-5, and AO01057-5) at KBREC were retained for
further evaluation (Table 3). Of these, AO98282-5 had the most attractive tuber
appearance for fresh market. AO96365-2 tended to be quite round and most suitable for
processing into chips. AO96164-1 and AO96141-3 have both performed exceptionally
well in the Western Regional trial. Both have produced very consistent processing
quality across all Tri-state (Oregon, Washington, and Idaho) locations. Oregon plans to
lead the release of AO96164-1 in 2008. As seen in the Preliminary Yield trial, specific
gravities were generally very high with the majority of entries exceeding the 1.088
threshold at which processing contracts begin to assess penalties. Total yields of retained
selections were generally comparable to the four standard entries. U.S. No. 1 yields were
generally higher than those of Russet Burbank and lower than Russet Norkotah with the
exception of AO96365-2 and AO01057-5 (Table 3).
Western Regional Trial
Excellent stands were achieved by all entries in the trial. All entries were later in
maturity than Russet Norkotah (Table 4). A relatively high incidence of hollow heart
was observed for A96104-2, AOTX95265-2ARu and TXA549-1Ru. Vascular
discoloration was problematic for A97287-6 and corky ringspot was observed in varying
degrees in nearly every entry. Russet Norkotah has rarely exhibited corky ringspot
(CRS) symptoms in the Klamath Basin which suggests a possible difference in virus
strains compared to the Columbia Basin where Russet Norkotah routinely shows CRS
symptoms. Other entries exhibiting zero or low CRS symptoms were AO96164-1,
AOTX95265-3Ru, CO97087-2Ru, and CO97138-7Ru. Standard varieties produced total
yields similar to those observed in the Statewide Trial (Table 5). Seven selections have
been included in the trial for 3 years and have graduated. The disposition of these
selections will be determined by the sponsoring states. A95409-1, A96104-2,
AOA95154-1, and AOA95155-7 are Idaho selections, AO96164-1 is an Oregon
selection, CO95172-3Ru is from Colorado, and TXA549-1Ru is a Texas selection.
Release decisions have not been made for any of these selections with the exception of
AO96164-1 which is planned for release in 2008. Three selections dropped for various
reasons included A97287-6, CO97138-3Ru, and CO97138-7Ru. Selections producing
acceptable yields and attractive tuber appearance comparable to Russet Norkotah at
KBREC include A96104-2 and AOTX95265-4Ru. Both of these selections will be
evaluated in cultural management trials at KBREC in 2008.
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Klamath Basin Research and Extension Center
Russet Potato Variety Development, 2007 Page 4
Research in the Klamath Basin
20 07 Annual Report
Table 1. Tuber yield and specific gravity of potato entries selected from the Preliminary Yield Trial grown
at the Klamath Basin Research and Extension Center, Klamath Falls, OR, 2007.
Variety or
selection
Yield U.S. No. 1s
4-8 oz 8-12 oz >12 oz
Yield
Specific
total
<4 oz
No. 2s
culls
total
gravity
cwt/acre
Russet Burbank
120
116
75
311
52
162
136
661
1.093
Ranger Russet
90
177
133
399
64
90
35
588
1.099
Shepody
59
108
158
325
25
185
123
658
1.077
Russet Norkotah
122
156
130
409
48
64
49
570
1.082
AO01114-4
53
124
238
416
26
38
27
507
1.099
AO02060-3
45
167
283
495
28
73
33
628
1.097
AO02118-2
81
120
225
426
28
64
20
538
1.084
AO03003-3
121
255
167
543
102
49
39
733
1.082
AO03096-5
156
176
54
385
61
44
7
497
1.113
OR03085-5
181
194
124
499
20
32
6
557
1.097
OR03151-4
135
174
196
505
57
80
60
702
1.089
OR04018-5
49
172
172
393
44
80
57
574
1.094
OR04057-2
102
165
83
350
137
91
24
602
1.095
OR04062-1
142
165
51
357
63
24
13
457
1.100
POR05V016-2
149
222
147
518
54
52
5
629
1.085
Mean1
107
166
149
422
54
75
42
593
1.092
1
Mean for standard varieties and selected clones only.
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Klamath Basin Research and Extension Center
Russet Potato Variety Development, 2007 Page 5
Research in the Klamath Basin
20 07 Annual Report
Table 2. Characteristics of potato entries in the Oregon Statewide Trial grown at the Klamath Basin Research and Extension
Center, Klamath Falls, OR, 2007.
Variety or
selection
Percent Vine
stand
Tuber characteristics3
Vine
1
2
vigor maturity
skin color
Hollow
russeting eyes shape
heart
4
Internal
Corky
4
brown spot ring spot4
%
Russet Burbank
Ranger
Shepody
Norkotah
99
99
100
100
4.8
5.0
4.0
3.5
2.4
3.4
2.5
1.6
4.1
4.0
1.0
4.3
4.4
4.3
1.8
4.5
4.0
3.0
4.0
3.9
4.1
5.0
3.9
4.8
0
0
0
15
25
33
18
0
0
25
0
0
AO96164-1#
AO96141-3*
AO96305-3*
AO96365-2*
AO98282-5*
98
98
100
100
99
5.0
5.0
4.0
4.3
5.0
2.1
3.6
2.5
3.5
2.8
4.0
4.0
3.8
4.0
4.0
4.3
4.8
4.0
5.0
5.0
4.1
3.8
4.1
3.5
3.5
4.1
4.9
4.1
3.0
4.0
0
13
0
0
3
13
0
20
3
0
13
0
13
8
0
AO00057-2*
AO98259-6
AO98286-4
AO01057-5*
AO02027-6
99
98
95
99
99
4.3
3.5
3.3
4.0
5.0
3.1
2.8
2.6
2.3
1.9
4.0
4.0
3.0
4.1
4.0
4.5
4.5
3.0
4.8
4.3
4.1
3.8
4.3
3.8
3.8
3.8
3.8
3.5
3.6
3.9
0
0
0
0
0
13
15
28
3
8
5
0
25
0
3
AO02103-1
AO02182-1*
AO02183-2*
AO02196-5
OR03029-2
98
98
98
99
99
3.8
5.0
5.0
5.0
3.3
2.6
1.9
3.4
3.8
2.9
4.4
4.1
4.0
4.1
4.1
5.0
4.1
4.8
4.5
5.0
3.4
4.1
3.9
4.1
4.3
3.8
4.5
5.0
4.1
2.8
0
0
5
0
0
25
5
20
10
0
8
8
0
3
0
98.8
-------
4.3
-------
2.7
-------
3.8
-------
4.3
-------
3.9
-------
4.0
-------
1.8
194.4
5.1
12.4
122.8
21.5
5.7
224.1
NS
Mean
CV(%)
LSD (0.05)
1/
Vine vigor: 1 = small, weak; 5 = large, robust.
2/
Vine maturity: 1 = early; 5 = late.
3/
Skin color: 1 = light; 5 = dark.
Russeting: 1 = light; 5 = heavy.
Eyes: 1 = deep; 5 = shallow.
Shape: 1 = round, 5 = long.
4/
Percent in 10 large tuber sample
*Retained for further evaluation
#
To be released
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Klamath Basin Research and Extension Center
Russet Potato Variety Development, 2007 Page 6
Research in the Klamath Basin
20 07 Annual Report
Table 3. Tuber yield by grade and specific gravity in the Oregon Statewide Trial grown at the Klamath Basin Research
and Extension Center, Klamath Falls, OR, 2007.
Variety or
selection
4-8 oz
Yield U.S. No. 1s
8-12 oz >12 oz
Yield
total
Specific
Bs
No. 2s
culls
total
1
gravity rank
cwt/acre
Russet Burbank
Ranger
Shepody
Norkotah
159
86
66
136
101
139
98
150
22
126
106
116
281
350
270
402
86
74
37
51
84
60
115
29
61
20
45
15
512
504
468
497
1.093
1.096
1.085
1.078
13
7
14
3
AO96164-1#
AO96141-3*
AO96305-3*
AO96365-2*
AO98282-5*
154
82
91
239
157
101
127
124
151
132
42
145
34
90
96
296
355
248
479
385
89
73
156
65
67
29
98
4
37
34
10
39
8
5
31
425
565
416
587
518
1.087
1.101
1.093
1.092
1.100
11
6
15
1
4
AO00057-2*
AO98259-6
AO98286-4
AO01057-5*
AO02027-6
110
110
169
146
100
132
135
136
158
101
94
40
57
127
17
336
284
363
430
218
43
34
54
43
61
37
34
31
24
117
14
19
26
8
54
430
371
474
505
450
1.089
1.084
1.077
1.088
1.091
8
12
5
2
18
AO02103-1
AO02182-1*
AO02183-2*
AO02196-5
OR03029-2
106
96
48
97
137
122
128
113
96
26
95
103
62
44
4
323
326
223
236
167
30
47
151
68
195
60
24
35
76
18
25
13
34
46
9
438
410
443
426
390
1.086
1.078
1.100
1.101
1.106
10
9
17
16
19
120.3
24.8
42.2
119.4
24.3
41.1
74.7
47.2
49.9
314.4
22.4
99.6
75.1
26.3
28.0
49.7
41.3
29.1
25.4
61.6
22.2
464.6
16.0
105.4
1.091
0.3
0.005
Mean
CV (%)
LSD (0.05)
1/
Rank: ranking in total U.S. No. 1 yield for KBREC out of 19 entries.
*Retained for further evaluation
#
To be released
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Klamath Basin Research and Extension Center
Russet Potato Variety Development, 2007 Page 7
Research in the Klamath Basin
20 07 Annual Report
Table 4. Characteristics of potato entries in the Western Regional Russet Trial grown at the Klamath Basin Research and
Extension Center, Klamath Falls, OR, 2007.
Variety or
Percent Vine
Tuber characteristics3
Vine
1
2
vigor maturity
Hallow
skin color russeting eyes shape
heart
4
Vascular
Corky
4
discoloration ring spot4
selection
stand
Ranger Russet
Russet Burbank
Russet Norkotah
%
98
100
99
4.3
5.0
4.0
3.9
2.9
1.8
3.9
4.0
4.3
4.4
4.8
5.0
3.1
3.9
3.9
5.0
4.4
4.5
0
0
5
%
0
0
0
58
23
0
A95409-1
A96104-2
A97287-6
AC96052-1RU
AO96141-3
100
100
98
99
100
4.0
4.8
5.0
5.0
5.0
3.8
2.8
3.6
3.3
3.5
3.4
4.0
3.4
4.3
3.8
3.9
4.9
4.0
5.0
4.9
3.5
3.5
3.1
4.0
3.8
3.8
4.3
4.0
3.6
4.9
0
33
0
5
0
5
3
20
3
3
28
15
13
28
20
AO96164-1
AOA95154-1
AOA95155-7
AOTX95265-2ARu
AOTX95265-3Ru
100
99
100
96
99
5.0
4.8
4.5
4.3
4.5
2.5
3.4
3.5
2.0
2.5
4.0
4.0
3.6
4.5
4.4
4.5
4.8
4.8
5.0
5.0
4.0
4.1
4.1
3.9
3.8
4.6
3.9
3.8
4.0
4.5
0
3
0
10
5
0
0
0
5
3
3
18
15
8
3
AOTX95265-4Ru
CO95172-3RU
CO97087-2RU
CO97138-3RU
CO97138-7RU
TXA549-1Ru
98
99
99
99
98
99
4.5
5.0
4.3
4.0
3.3
4.3
2.1
3.5
2.6
2.0
3.4
3.8
4.1
4.0
3.9
4.0
3.8
4.0
5.0
5.0
4.9
5.0
4.0
4.4
3.8
3.8
4.0
4.0
3.6
4.0
4.4
4.0
4.4
4.3
4.6
3.0
8
3
0
0
3
13
0
0
0
0
3
0
5
18
0
5
0
5
Mean
CV (%)
LSD (0.05)
99
-------
4.5
3.0
-------
4.0
-------
4.7
-------
3.8
-------
4.2
-------
4.5
134.5
8.5
2.2
240.3
7.6
13.7
147.9
28.7
1/
Vine vigor: 1 = small, weak; 5 = large, robust.
Vine maturity: 1 = early; 5 = late.
3/
Skin color: 1 = light; 5 = dark.
Russeting: 1 = light; 5 = heavy.
Eyes: 1 = deep; 5 = shallow.
Shape: 1 = round, 5 = long.
4/
Percent in 10 large tuber sample
2/
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Klamath Basin Research and Extension Center
Russet Potato Variety Development, 2007 Page 8
Research in the Klamath Basin
20 07 Annual Report
Table 5. Tuber yield by grade and specific gravity in the Western Regional Russet Trial grown at the Klamath
Basin Research and Extension Center, Klamath Falls, OR, 2007.
Variety or
selection
Yield U.S. No. 1s
4-8 oz 8-12 oz >12 oz
Yield
total
<4 oz
Specific
No. 2s
culls
total
1
gravity rank
cwt/acre
Ranger Russet
Russet Burbank
Russet Norkotah
89
119
126
146
113
152
90
65
144
325
297
422
70
76
53
74
109
59
26
46
16
495
528
549
1.097
1.091
1.075
13
14
3
A95409-1
A96104-2
A97287-6
AC96052-1RU
AO96141-3
99
100
115
101
52
130
156
139
90
97
174
112
100
49
63
403
368
354
239
211
41
58
48
46
96
68
36
84
15
53
11
10
24
15
31
522
472
510
315
391
1.095
1.086
1.090
1.088
1.101
4
6
8
18
19
AO96164-1
171
AOA95154-1
126
AOA95155-7
125
AOTX95265-2ARu 94
AOTX95265-3Ru
98
117
122
94
132
130
94
37
34
141
110
382
285
254
368
338
82
75
70
41
50
120
13
44
44
62
15
3
5
27
39
599
376
372
479
489
1.090
1.091
1.083
1.076
1.078
5
15
16
7
12
AOTX95265-4Ru
CO95172-3RU
CO97087-2RU
CO97138-3RU
CO97138-7RU
TXA549-1Ru
82
160
124
83
90
88
127
134
83
145
135
130
134
52
37
117
229
209
344
346
244
346
454
427
39
85
60
30
31
30
57
49
92
31
78
79
22
17
16
10
25
42
461
497
412
417
589
578
1.077
1.095
1.090
1.079
1.077
1.088
11
9
17
10
1
2
Mean
CV (%)
LSD (0.05)
107
25
39
125
25
44
105
45
67
337
20
96
57
26
21
61
51
44
21
82
25
476
14
94
1.087
0.362
0.006
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1/
Rank: ranking in total U.S. No. 1 yield for KBREC out of 19 entries.
______________________________________________________________________________
Klamath Basin Research and Extension Center
Russet Potato Variety Development, 2007 Page 9