R. Jay Goos and
Brian Johnson, Department of Soil Science, NDSU, Fargo, ND 58105
e-mail: rj.goos@ndsu.edu
Field studies
were set out at five locations in 2006, to measure the resistance of about 180
soybean varieties to iron chlorosis.
The sites were located near Arthur, Colfax, Galchutt, Galesburg, and
Prosper, ND. The sites ranged in
pH from 8.1 to 8.3, salinity (EC) from 0.2 to 0.8 mmho/cm, and CaCO3
contents ranging from 2 to 8 %.
Thirty five seeds were planted in short (5Õ) rows on 30-inch
centers. The experimental design
was a randomized complete block with four replications at each site.
Visual ratings
were made on a 1-5 scale, with 1=representing no chlorosis and 5= the most
severe chlorosis. Ratings
were taken at the 2-3 trifoliolate, 5-6 trifoliolate, and two weeks after the
5-6 trifoliolate stage. Only the
first two ratings were made at Prosper, due to recovery from chlorosis. The Galchutt site was lost, due to an
unusually heavy white grub infestation.
Ten ÒstandardÓ
varieties were entered, to help in the interpretation of the results. The varieties, listed in expected order
from the most resistant to most susceptible, were Iowa State ISU A11 > Seeds 2000 2070RR
> Traill = Council > Asgrow
0801 = Peterson PFS 0202RR > Glacier >Mycogen 5072 = Stine 0480 = NuTech
0505RR. The variety ISU A11
represents the highest level of chlorosis resistance available in current
breeding lines. All standards were entered twice, to show the degree of
variation in our ratings.
The summary of
the chlorosis scores, averaged across site and the three ratings, are shown in
Table 1. Each chlorosis rating in Table 1 represents the average of 44
observations. The year 2006 was an
unusual year, with below-normal precipitation. Overall chlorosis was greater in 2006 than in prior years,
perhaps due to intensification of salinity effects in a dry year.
The ÒstandardÓ
varieties are listed in bold typeface in Table 1. The standards
at the top (ISU A11, Seeds 2000 2070RR) and at the bottom (Glacier, Mycogen
5072, Stine 0480, NuTech 0505RR) came out exactly as expected. The varieties Òin the middleÓ came out in a very narrow range. Traill, Council, Asgrow 0801, and PFS 0202RR
were in a range of +/- 0.2 chlorosis unit, when the data were averaged.
Chlorosis
severity differs from year to year, and it is impossible to give exact
recommendations as to what level of chlorosis resistance is appropriate for a
specific field. In general, the
more severe the chlorosis a field produces, the higher on the list a farmer
should be, consistent with other agronomic considerations, such as maturity.
This report is
also available online at: www.yellowsoybeans.com
This
research was sponsored by the North Dakota Soybean Council.
Table
1. Average chlorosis scores,
across two ratings and five locations, North Dakota, 2006.
|
Company |
Variety |
Avg |
|
Standard |
ISU A11 |
1.6 |
|
Standard |
ISU A11 |
1.7 |
|
Univ. of MN |
M00-307055 |
1.7 |
|
Canterra Seeds |
PR 416905 |
1.8 |
|
Croplan
Genetics |
RT0043 |
1.8 |
|
Proseed |
RR 50-045 |
1.9 |
|
Standard |
S2000 2070 RR |
1.9 |
|
NorthStar |
NS0021 RR |
1.9 |
|
NorthStar |
NS0011 RR |
1.9 |
|
Univ. of MN |
M98-108027 |
2.0 |
|
Gold Country
Seed |
426 RR |
2.0 |
|
Proseed |
RR 60-95 |
2.0 |
|
Pioneer |
90M01 |
2.1 |
|
Standard |
S2000 2070 RR |
2.1 |
|
Nutech |
0066 RR |
2.1 |
|
Wensman |
W20051 RR |
2.1 |
|
Pioneer |
PHI SoyVar 2-06 |
2.1 |
|
Sabre |
0206-15 RR |
2.1 |
|
Dekalb |
EXP 5007 A |
2.2 |
|
Legend Seeds |
LS 0707 RR |
2.2 |
|
Peterson Farms
Seed |
07006 RR |
2.2 |
|
Prairie Brand
Seed |
PB-0796 RR |
2.2 |
|
Stine |
0056-4 |
2.2 |
|
Stine |
0063-4 |
2.2 |
|
Thunder Seeds |
703 RR |
2.2 |
|
Thunder Seeds |
709 RR |
2.2 |
|
Kruger Seed |
K-042 RR |
2.2 |
|
Roughrider
Genetics |
RG 601NRR |
2.2 |
|
Peterson Farms
Seed |
0709 RR |
2.2 |
|
NuTech |
0706+RR |
2.3 |
|
Prairie Brand
Seed |
PB-00736 RR |
2.3 |
|
Company |
Variety |
Avg |
|
Prograin |
PR 6231 A02 rr |
2.3 |
|
Gold Country
Seed |
2703 RR |
2.3 |
|
Ziller |
Exp 45103R |
2.3 |
|
Proseed |
RR 60-06 |
2.3 |
|
Univ. of MN |
M00-327021 |
2.3 |
|
Stine |
0306-4 |
2.3 |
|
Croplan
Genetics |
RT0406 |
2.3 |
|
NuTech |
0525 RR |
2.3 |
|
Thunder Seeds |
707 RR |
2.3 |
|
Roughrider
Genetics |
RG 607RR |
2.3 |
|
Proseed |
RR 60-40 |
2.3 |
|
Thunder Seeds |
27007 RR |
2.3 |
|
Standard |
Council |
2.4 |
|
NuTech |
0706 RR |
2.4 |
|
Legend Seeds |
LS 0057 RR |
2.4 |
|
Legend Seeds |
LS 0624 RR |
2.4 |
|
Nutech |
0090+RR |
2.4 |
|
Production
Partners |
0055 RR |
2.4 |
|
Legend Seeds |
LS 0406 RR |
2.4 |
|
Standard |
Asgrow 0801 RR |
2.4 |
|
Standard |
Traill |
2.4 |
|
Garst |
0312RR |
2.4 |
|
Wensman |
W2086 RR |
2.4 |
|
Hyland Seeds |
RR Royal |
2.4 |
|
Univ. of MN |
M00-307023 |
2.4 |
|
Ziller |
BT 7102R |
2.4 |
|
Stine |
0060-64 |
2.4 |
|
Thunder Seeds |
27005 RR |
2.4 |
|
Wensman |
W20074 RR |
2.4 |
|
Gold Country
Seed |
3709 RR |
2.5 |
|
Dyna-Gro |
30A06 |
2.5 |
|
Proseed |
RR 50-07 |
2.5 |
|
Company |
Variety |
Avg |
|
Legend Seeds |
LS 0255 RR |
2.5 |
|
Wensman |
W2030 RR |
2.5 |
|
Mycogen |
Atlas 5B034 |
2.5 |
|
Mycogen |
Atlas 5A009 |
2.5 |
|
Garst |
0549RR |
2.5 |
|
Kruger Seed |
K-009+RR |
2.5 |
|
Kruger Seed |
K-086 RR |
2.5 |
|
Proseed |
RR 60-05 |
2.5 |
|
Asgrow |
AG 0301 |
2.5 |
|
Croplan
Genetics |
RT0669 |
2.5 |
|
Standard |
PFS 0202 RR |
2.5 |
|
Dyna-Gro |
32T03 |
2.5 |
|
Hyland Seeds |
RR Reliant |
2.5 |
|
Prairie Brand
Seeds |
PB-00576 RR |
2.5 |
|
Standard |
Council |
2.5 |
|
Standard |
Traill |
2.5 |
|
Wensman |
W2064 RR |
2.5 |
|
Hyland Seeds |
RR Richwood |
2.5 |
|
Prairie Brand
Seed |
PB-0356 RR |
2.5 |
|
Prairie Brand
Seeds |
PB-0856 RR |
2.5 |
|
Production
Partners |
0701+RR |
2.5 |
|
Standard |
PFS 0202 RR |
2.6 |
|
Mycogen |
Atlas X56006 |
2.6 |
|
NuTech |
0330+RR |
2.6 |
|
Gold Country
Seeds |
923 RR |
2.6 |
|
Hyland Seeds |
RR Ridgeway |
2.6 |
|
Pioneer |
PHI SoyVar 3-06 |
2.6 |
|
Wensman |
W20092 RR |
2.6 |
|
Pioneer |
PHI SoyVar 1-06 |
2.6 |
|
Standard |
Asgrow 0801 RR |
2.6 |
|
Kruger Seed |
K-120 RR |
2.6 |
|
Sabre |