Klamath Experiment Station
Potato Variety Screening Trials, 1997
K.A. Rykbost and J. Maxwell'
A
bstract
The Oregon Potato Variety Development Program evaluates approximately
80,000 single-hill selections annually from
breeding programs in Idaho, Colorado, and
North Dakota. The Klamath Experiment Station
(KES) participates in the overall effort by conducting replicated yield trials at the preliminary,
statewide, and western regional levels. In 1997,
two additional trials were conducted to evaluate Russet Norkotah, Russet Burbank, and
Shepody clones developed at Oregon State University through transgenic techniques. Over 125
selections were included in these trials at KES
in 1997.
Two Oregon selections will be released in
early 1998. Umatilla Russet (A082611-7) is a
processing russet that has performed very well for
French fry production in the Columbia Basin of
Oregon and Washington. Over 400 acres of
A082611-7 seed were certified in 1997. Russet
Legend (CO083008-1) has performed well for
French fry production in the Treasure Valley of
Eastern Malheur County. Oregon, and Southwestern Idaho, and for fresh market in Eastern
Idaho. Over 160 acres of CO083008-1 seed
passed certification in 1997. Several other
Oregon selections in advanced stages of evaluation appear to be candidates for release. Three
russet-skinned selections and two round-white
selections from the statewide trial will be ad-
vanced to regional trials in 1998. Most of the
entries in the 1997 statewide trial exceeded the
standard varieties in yield, quality, or both.
Several of the OSU transgenic clones are resistant to potato virus Y and were not significantly
different than standard varieties in yield or quality.
The transgenic selections will be considered in a
separate report.
Introduction
Considerable progress has been made in
the past 10 years improving potato varieties.
Russet Burbank, the long-time industry standard
for fresh market and French fry production,
requires high inputs and is vulnerable to several
physiological disorders. It is no longer the dominant variety in the Klamath Basin or the Treasure
Valley. New varieties have also captured a
significant portion of the Columbia Basin acreage;
however, the newer varieties replacing Russet
Burbank also have weaknesses. Traditional
breeding programs continue to produce selections
with superior quality for specific markets. Recently, through genetic engineering techniques,
standard varieties have been altered to incorporate disease or pest resistance or to improve
other characteristics. A third area being pursued
is line selections within a variety. Examples from
all of these methods were included in material
evaluated in the Oregon statewide program in
'/ Superintendent/Professor and Biological Sciences Research Technician III, respectively, Klamath
Experiment Station. Klamath Falls, OR.
Acknowledgments: Financial support for this program from the Oregon Potato Commission; the Cooperative State Research. Education, and Extension Service (CSREES); and the USDA Agricultural Research
Service (ARS) is gratefully recognized.
12 Klamath Experiment Station 1997
Klamath Experiment Station
Potato Variety Screening Trials, 1997
1997. This report summarizes the performance of selections in the Oregon and
regional programs at Klamath Falls.
Procedures
All trials were conducted on a Poe
fine sandy loam soil in a 2-year rotation with
spring cereals. Nematodes and related
diseases were controlled with 18 gallons per
acre (gpa) of soil fumigant Telone II applied at
about 16-inch depth on 18-inch centers with
a ripper on October 22, 1996. All seed lots
were hand cut to approximately 1.5 to 2.5
ounces (oz) per seedpiece, treated with
thiophanate-methyl (Tops 2.5), at 1.0 pound
per hundred pounds (lb/cwt), and suberized
at about 55 °F and 95 percent relative
humidity for 10 to 14 days before planting.
Potatoes were planted at 8.7-inch
spacing in 32-inch rows with an assisted-feed,
two-row planter in all trials. Insecticide Disyston was applied in the seed furrow at 3.0
lb active ingredient (a.i.)/acre at planting.
Fertilizer was banded on both sides of rows
at 1000 lb/acre of 16-8-8-14. Weeds were
controlled with Eptam applied at 3.0 lb a.i./
acre with a conventional ground sprayer and
incorporated immediately with a rolling
cultivator on May 28, and Matrix applied at
1.5 oz (0.0234 lb a.i.)/acre on June 23 and
incorporated with 0.5 inches of irrigation
water. Irrigation was applied twice weekly
with solid-set sprinklers arranged on 40-foot
by 48-foot spacing. Total crop water, including irrigation and rainfall, was approximately
24 inches.
All trials were planted on May 19.
The preliminary-yield trial included 5 standard
varieties and 67 numbered selections in 20-hill
plots with 2 replications. Five standard varieties
and 19 numbered selections were included in the
statewide trial. The regional trial included 3
standard varieties, 10 numbered selections, and 5
line selections of Russet Norkotah. All trials were
arranged in a randomized complete block design
and, except in the preliminary trial, included 30hills/plot with 4 replications.
Fungicides, applied aerially, included
Bravo at 1.0 lb a.i./acre on July 5, Ridomil-MZ at
1.5 lb a.i./acre on July 17, Kocide at 2.0 lb a.i./
acre on August 9, and Bravo at 2.0 lb a.i./acre on
August 29. Monitor was applied with the fungicides at 0.75 lb a.i./acre on July 17 and August
29. Vines were desiccated with Diquat applied
with a ground sprayer at 1.0 pint/acre on September 2 and September 7 for the western regional
trial and September 7 and September 11 for
preliminary and statewide trials. Kocide was _ .
applied with the Diquat at 2.0 lb a.i./acre on
September 7. Vines were shredded with a
rotobeater one day before harvest.
Potatoes were harvested with a one-row
digger-bagger on September 29 (western regional),
September 30 (preliminary trial), and October 1
(statewide trial). All tubers from each plot were
stored at about 55 °F and 95 percent relative humidity until tubers were graded in late October.
External tuber characteristics were noted for
each replication during grading. Ten large (usually
over 10 oz) tubers from each plot were cut lengthwise and inspected for internal defects. Air and water
weights were used to determine specific gravity on
samples of approximately 10 lb of U.S. No. ls in the
8- to 12-oz size. USDA grade standards were
followed to separate B size (< 4 oz), U.S. No. ls (4
to 12 oz and > 12 oz), U.S. No. 2s, and culls
Klamath Experiment Station 1997 13
Klamath Experiment Station
Potato Variety Screening Trials, 1997
categories. U.S. No. 1 yields were not adjusted
for external blemishes such as rhizoctonia or
scab or for internal defects such as hollow
heart or brown center. Samples of 6- to 12-oz
tubers were saved from one replication of each
selection in all trials to evaluate culinary
quality.
French fry tests were conducted to
determine fry color on entries in preliminary,
statewide, and western regional trials. Samples
from the western regional and statewide trials
were also evaluated for boiling, oven baking, and
microwave preparation methods. The culinary
tests were designed to detect serious deficiencies
such as severe sloughing, off- flavors, aftercooking darkening, or poor texture. Tests were
conducted in early November.
Because the preliminary trial only included
two replications, data were not subjected to
statistical analyses. In other trials, yield, grade,
and specific gravity data were statistically analyzed using MSTAT software. Only a portion of
the data collected is presented in this report.
Decisions on the disposition of selections at all
levels of evaluation are based on data accumulated at all trial locations. Preliminary and statewide trial data from four Oregon trial sites
(Hermiston, Ontario, Powell Butte, and Klamath
Falls) are compiled and reviewed by members of
the Oregon Variety Development Committee.
Cooperators at Aberdeen, Idaho compile tri-state
and western regional trial data, which is reviewed
at annual committee meetings attended by up to
30 cooperators and industry representatives.
Results and Discussion
The 1997 growing season was generally
very favorable for the potato crop at Klamath
Falls. The only frost affecting trials occurred on
14 Klamath Experiment Station 1997
June 22 when plants were just emerging. The
crop was protected with sprinkler irrigation and
no damage to emerged plants was observed.
Plants of many of the selections were unusually
vigorous. Vines were difficult to desiccate at
season-end. Yields were high to very high in many
selections. Tuber size was larger than usual and
selections with a tendency for malformations
exhibited knobs, growth cracks, and skin abnormalities. For example, Russet Burbank had over
20 percent No.2s and culls in the preliminary,
statewide, and regional trials. In each of these
trials, Russet Burbank ranked very low in yield of
No.ls.
Preliminary Yield Trial
Most of the entries in this trial were
selections from crosses made at Aberdeen,
Idaho, in 1992 and 1993. Several entries had
excessive vine growth, and immature skins at
harvest which resulted in serious skinning damage.
Yields were generally very high but several of the
selections, including Russet Burbank and
Shepody, had many off-type, rough, or growthcracked tubers. Russet Burbank ranked 26th in
total yield but only 60th out of 72 entries in No. I
yield. Russet Norkotah produced 115 cwt/acre
less total yield, but 33 cwt/acre more No. 1 yield
than Russet Burbank. The conditions of this trial
provided a good opportunity to detect weaknesses in tuber type and uniformity. Similar
conditions and results were experienced at Powell
Butte, the other short-season trial location.
After reviewing data from all locations, 11
clones were selected for further evaluation (Table
1). All of these are russet-skinned lines. Several
selections had adequate dry matter content and
fry color for processing as French fries. Ranking
in No. 1 yields across four locations ranged from
Klamath Experiment Station
Potato Variety Screening Trials, 1997
1st for A093317-5, which produced the highest
No. I yield at three locations, to 32nd for
A092281-3. None of the clones saved were
equal to Russet Norkotah in tuber type and
appearance. Entries selected from this trial were
advanced to the statewide trial.
Statewide Trial
Crop development in this trial was similar
to conditions experienced in the preliminary trial.
Most selections had vigorous vine growth at the
time of top killing (Table 2). All selections had
later vine maturity than Russet Norkotah. Hollow
heart incidence was quite high in Atlantic and
three numbered selections, although in most cases
the tubers involved were very large, particularly in
A085165-1.
The performance of standard varieties
was similar to results observed in the preliminary
trial. Russet Burbank produced a high total yield,
but it had many No. 2s and culls (Table 3).
Although Russet Norkotah had 130 cwt/acre less
total yield than Russet Burbank, No. 1 yield was
45 cwt/acre higher. At KES and across all
locations, Russet Burbank ranked 23rd out of 24
entries in yield of No. ls. The overall quality and
performance of entries in this trial was very good.
Most of the Russet-skinned selections were
attractive in appearance, had relatively good tuber
type, produced high yields, and had fewer
external and internal defects than Russet Burbank.
The two round white chipping selections,
A091812-1 and A091812-2, ranked 1st and
2nd, respectively, in No. 1 yields across all
locations.
Only three selections from this trial were
discarded from the program. The official release
of A082611-7 as Umatilla Russet and
C0083008-1 as Russet Legend is planned for
early 1998. Both selections have good processing
quality. Russet Legend is considered acceptable
for fresh market by growers in Eastern Idaho.
A085165-1, an attractive fresh market russet,
completed three years of evaluation in the regional
trial in 1996, was increased in greenhouse culture
in 1997, and will be supplied to seed growers for
rapid increase and commercial evaluation. It
resembles Russet Norkotah, which was the male
parent, in appearance, and typically exceeds
Norkotah in No. 1 yield by 100 cwt/acre or
more.
The russet selection A087277-6 was
included in the western regional trial for the first
time in 1997. It will remain in the 1998 regional
trial as a dual purpose line, suitable for processing
and fresh market use. Another dual purpose
russet, A089128-4, was included in the 1997 tristate trial and will advance to the regional trial in
1998. A090014-1 and A088103-3 are being
advanced to the tri-state trial and are considered
dual purpose, attractive russets. A090319-1 was
probably the most attractive russet-skinned
selection in this trial. It has very nice yellow flesh
color. This selection will be entered in the regional
specialty variety trial in 1998. It produced lower
yields than most other clones in both 1996 and
1997.
The chipping selections, A091812-1 and
A091812-2, will advance to the regional chipping trial in 1998. Both lines produce very high
yields. Late vine maturity and attached stolons
were noted in both selections at KES in 1997.
Six additional selections will be retained in the
statewide trial in 1998 (Table 3).
Western Regional Trial
Three Texas and two Colorado line
selections of Russet Norkotah were included in
Klamath Experiment Station 1997 15
Klamath Experiment Station
Potato Variety Screening Trials, 1997
this trial. All had later vine maturity than the
standard Russet Norkotah entry (Table 4). The
Colorado selections CORN-3 and CORN-8 and
the Texas selection TXNS 223 were entered in
the regional trial for the first time in 1997. In 1996
trials, TXNS 112 and TXNS 278 were only
slightly later in vine maturity than the standard
Russet Norkotah across seven locations. The
1997 KES data shows much later vine maturity
for CORN-3 and TXNS 278. All Norkotah line
selections were equal to or higher than the
standard Russet Norkotah in specific gravity.
CORN-3 had a high incidence of hollow heart.
This selection produced very large tubers compared to the other Russet Norkotah selections.
The relative yields of Russet Burbank and
Russet Norkotah standards were the same as
observed in preliminary and statewide trials
(Table 5). Russet Burbank had the lowest yield of
No. ls and the highest yield of No. 2s and culls
of all entries. CORN-3 achieved the highest No.
I yield, but tuber size was excessive. CORN-3
and CORN-8 produced significantly higher No. 1
yields than the standard Russet Norkotah. TXNS
278 was the lowest yielding Norkotah line
selection.
A8495-1 was not an official trial entry in
1997. It has completed three years of evaluation
in the regional trial and is being evaluated commercially. This selection has looked very promising as a fresh market selection for the Klamath
Basin. It has not produced high yields in KES
trials but has very attractive tubers and excellent
culinary quality. In this trial, A8495-1 exceeded
Russet Burbank in No. 1 yields by 52 cwt/acre.
All other selections produced higher No. 1 yields
than A8495- l in the 1997 KES regional trial.
Three entries; A82360-7, C085026-4,
and TXAV657-27Ru, have completed three
16 Klamath Experiment Station 1997
years in regional trials. Two selections, A8792-1
and C087009-4, were discarded. All other
selections in the 1997 trial will be continued in the
program. The Colorado and Texas strain selections of Russet Norkotah have undergone exten- _
si ve seed increase and will constitute a significant
portion of 1998 acreage in these states. Averaged
over nine regional trial sites in 1997, all of these
strains produced higher No. 1 yields than the
standard Norkotah by 20 to 80 cwt/acre.
Conclusions
The quality of advanced selections in the
Oregon and regional potato variety development
programs is excellent. Oregon will formalize
releases for Russet Legend and Umatilla Russet in
1998. Idaho plans to release a round white
chipping selection, ND01496-1, which was
selected from the Oregon program; a red-skinned
selection, A82705-1R as Idarose; and two
russeted selections, A81473-2 and A8495-1,
which will be named Classic Russet, in 1998.
Colorado plans to release a russet selection,
AC83064-6, and a red-skinned selection,
DT6063-1R in 1998. Releases planned for the
near future in Texas include a round white chipping selection, ATX85404-8, and a russet
selection, TXAV657-27Ru. Texas and Colorado
continue moving forward with development of
Russet Norkotah strain selections. Based on
evaluation of the russet skinned selections at
KES, A8495-1 may be the best candidate as a
fresh market russet for the local industry.
Klamath Experiment Station
Table 1. Tuber yield and specific gravity of entries selected from the Preliminary Yield Trial for further
evaluation, Klamath Falls, OR, 1997.
Variety/
selection
Yield U.S. No. ls
4-12 oz
> 12 oz total
Bs
Yield
No. 2s
culls
total
Specific
gravity
cwt/A
Russet Burbank
Ranger Russet
Shepody
Russet Norkotah
Atlantic
332
307
159
283
397
59
180
279
141
121
391
487
438
424
518
77
55
17
39
92
28
51
0
14
0
102
13
65
7
22
598
606
519
483
632
1.085
1.086
1.082
1.069
1.095
C0093031-3
A092130-2
A092246-3
AO92252-1
A092260-8
303
389
435
295
408
337
196
130
344
150
640
585
565
639
558
24
52
68
33
59
0
0
6
23
15
5
30
0
6
36
669
667
639
701
668
1.080
1.083
1.081
1.086
1.083
A092270-4
A092281-3
A092303-3
A092304-1
A092378-1
A093317-5
333
438
391
347
264
488
119
101
127
46
195
183
452
539
518
393
459
671
50
39
34
103
33
42
0
12
7
4
0
0
4
2
72
14
23
10
506
592
631
514
515
723
1.088
1.090
1.100
1.082
1.082
1.083
Mean'
348
169
517
51
10
26
604
1.085
1/
Mean for standard varieties and clones selected only.
Klamath Experiment Station 1997 17
Klamath Experiment Station
Table 2. Characteristics of entries in the Oregon Statewide Trial, Klamath Falls, OR, 1997.
Variety/
Percent
Vigor
Vine
Specific
selection
stand
rating'
maturity2
gravity
Russet Burbank
Ranger Russet
Shepody
Russet Norkotah
Atlantic
93
92
93
93
87
3.5
4.0
3.0
3.3
3.8
3.3
3.0
3.5
2.0
3.3
1.088
1.079
1.075
1.069
1-.092
8
0
5
8
20
A082611-7
C0083008-1
A085165-1
A087277-6
A089128-4
95
98
96
96
98
3.0
2.8
2.3
3.5
3.5
3.3
3.8
3.5
3.8
3.5
1.084
1.087
1.078
1.085
1.094
5
11
18
3
3
A090014-1
C0090319-1
A088103-3
A091522-4
A091812-1
95
99
98
96
96
3.5
2.8
3.3
2.3
3.0
3.5
4.0
4.3
3.8
4.0
1.085
1.082
1.081
1.079
1.086
0
3
18
5
3
A091812-2
A092007-2
A092016-2
A092016-3
A092017-6
97
96
94
96
98
4.3
3.5
2.5
2.5
2.8
3.8
4.0
3.0
3.5
4.3
1.085
1.084
1.076
1.079
1.083
3
3
0
3
0
A092019-13
A092023-3
A092056-7
A092173-2
97
96
94
92
2.0
3.5
2.0
3.3
4.3
3.0
3.8
4.5
1.084
1.08
1.081
1.079
8
5
0
35
Mean
LSD (P = 0.05)
95
3.1
3.6
1.082
0.005
7
1
/ Vigor rating: 1 a small, weak plant to 5, a large, robust plant.
2
/ Vine maturity: 1 for early to 5 for late.
3
/ H.H.
& B.C.: hollow heart plus brown center in 10 large tubers/sample.
18 Klamath Experiment Station 1997
Percent
H.H. & B.C.'
Klamath Experiment Station
Table 3. Tuber yield by grade for entries in the Oregon Statewide Trial, Klamath Falls, OR, 1997.
Variety/
Selection
Yield U.S. No. is
4-12 oz
> 12 oz
total
Bs
Yield
No. 2s
culls
total
cwt/A
Russet Burbank
Ranger Russet
Shepody
Russet Norkotah
Atlantic
240
255
204
284
359
89
152
185
90
131
329
407
389
374
490
61
29
18
44
37
57
17
49
4
17
108
8
27
4
21
555
461
482
425
565
A082611-7
00083008-1*
A085165-1*
A087277-6'
A089128-4*
300
217
284
365
372
122
262
253
148
115
421
479
537
513
487
60
15
28
42
38
25
14
15
12
44
18
12
8
11
12
523
520
588
578
580
A090014-1*
A090319-1*
A088103-3*
A091522-4
A091812-1*
310
323
358
295
422
121
87
147
318
172
431
410
505
613
594
50
49
50
19
49
14
5
19
10
15
3
3
13
21
5
498
467
587
663
663
A091812-2*
A092007-2'
A092016-2
A092016-3*
A092017-6*
502
318
299
367
256
159
l 32
113
70
248
661
450
412
437
504
61
35
42
46
37
9
13
39
14
19
14
5
12
15
6
745
502
505
512
564
A092019-13'
A092023-3*
A092056-7
A092173-2'
357
348
264
280
91
118
41
230
447
466
305
510
32
42
40
30
21
38
15
52
21
8
3
30
520
553
363
622
Mean
CV (%)
LSD (P= 0.05)
316
18
82
150
36
76
465
17
113
40
36
20
22
82
26
16
88
20
543
15
112
* Retained for further evaluation
Klamath Experiment Station 1997 19
Klamath Experiment Station
Table 4. Characteristics of entries in the Western Regional Trial, Klamath Falls, OR, 1997.
Variety/
Percent
Vigor
Vine
Specific
selection
stand
rating
maturity2
gravity
H.H. & B.C. ;
98
98
93
97
98
3.5
3.8
2.3
2.8
3.8
4.3
3.8
2.3
4.5
4.5
1.084
1.085
1.070
1.086
1.090
l I
8
8
0
20
96
92
100
89
98
3.5
3.3
2.0
4.8
3.3
3.3
3.5
3.0
3.3
4.0
1.094
1.090
1.082
1.087
1.076
8
0
0
26
23
CORN-8
NDD840-1
TX1385-I2RU
TXAV657-27RU
TXNS 112
99
97
99
96
96
2.5
2.0
3.0
3.3
3.8
2.8
4.3
2.8
3.5
3.0
1.074
1.073
1.076
1.074
1.069
8
23
8
3
13
TXNS 2 23
TXNS 278
A8495-1
98
98
98
3.5
2.5
1.0
3.5
4.0
3.5
1.071
1.070
1.082
13
8
3
Mean
LSD (P = 0.05)
97
3.0
3.6
1.079
10
Russet Burbank
Ranger Russet
Russet Norkotah
A82360-7
A8792-I
AC87084-3
A087277-6
C085026-4
C0087009-4
CORN-3
0.006
1/
Vigor rating: l is a small. weak plant to 5, a large, robust plant.
2/
Vine maturity: 1 for early to 5 for late.
3
/ H.H. & B.C.: hollow heart plus brown center in 10 large tubers/sample.
20 Klamath Experiment Station 1997
Percent
Klamath Experiment Station
Table 5. Tuber yield by grade for entries in the Western Regional Trial, Klamath Falls, OR, 1997.
Variety/
selection
Yield U.S. No. ls
4-12 oz
> 12 oz
total
Yield
No. 2s
culls
total
cwt/A
Russet Burbank
Ranger Russet
Russet Norkotah
A82360-7
A8792-]
284
349
261
347
290
56
155
164
165
224
339
504
425
512
513
75
63
41
46
35
83
58
5
34
33
63
11
0
73
83
560
635
471
663
663
AC87084-3
A087277-6
C085026-4
C0087009-4
CORN-3
398
345
264
364
326
152
167
192
53
256
550
512
456
418
582
46
45
30
102
34
19
32
24
35
30
3
7
2
7
12
617
596
512
561
658
CORN-8
NDD840-1
TX1385-12RU
TXAV657-27RU
TXNS112
296
267
299
283
347
254
152
176
216
150
550
419
475
499
497
35
61
52
32
53
31
36
26
41
24
4
1
8
21
8
619
517
560
593
581
TXNS 223
TXNS 278
A8495-1 .
401
304
263
86
120
129
487
424
391
58
61
34
10
10
8
5
1
9
561
496
442
Mean
CV (7c )
LSD (P= 0.05)
316
17
74
159
39
89
475
16
109
50
35
25
30
74
31
18
84
21
572
14
111
Klamath Experiment Station 1997 21