SOYBEAN PERFORMANCE IN ONTARIO IN 2008


Clinton C. Shock, Erik B.G. Feibert, and Lamont D. Saunders

Malheur Experiment Station

Oregon State University

Ontario, OR


Introduction

Soybean is a potentially valuable new crop for the Pacific Northwest (PNW). Soybean can provide raw materials for biodiesel, high-quality protein for animal nutrition, and oil for human consumption, all of which are in short supply in the PNW. In addition, edible or vegetable soybean production can provide a raw material for specialized food products. Soybean is valuable as a rotation crop because of the soil-improving qualities of its residues and its nitrogen (N2)-fixing capability. Because high-value irrigated crops are typically grown in the Snake River Valley, soybeans may be economically feasible only at high yields. The most common rotation crop in the Treasure Valley is irrigated winter wheat, so soybeans need to be competitive in value with winter wheat. Through breeding, selection, and the development of appropriate cultural practices, we have succeeded in achieving high yields.

Soybean varieties developed for the midwestern and southern states are not necessarily well adapted to Oregon's lower night temperatures, lower relative humidity, and other climatic differences. Previous research at Ontario, Oregon has shown that, compared to the commercial cultivars bred for the Midwest, plants for eastern Oregon need to have high tolerance to seed shatter, reduced plant height and lodging, increased seed set, and higher harvest index (ratio of seed to the whole plant).

M. Seddigh and G.D. Jolliff at Oregon State University, Corvallis, identified a soybean line that would fill pods when subjected to cool night temperatures. This line was crossed at Corvallis with productive lines to produce 'OR 6' and 'OR 8', among others. At this point, the development moved to Ontario, Oregon. The two lines were crossed at our request for several years with early maturing high-yielding semi-dwarf lines by R.L. Cooper (USDA, Agricultural Research Service, Wooster, OH) to produce semi-dwarf lines with potential adaptation to the PNW. Selection criteria for F2 and subsequent lines at the Malheur Experiment Station (MES) included high yield, zero lodging, zero shatter, low plant height, and maturity in the available growing season. We specifically chose seed lines with clear hilum so that off colors would not contaminate possible food products. Also, we selected for light seed coat and seed color to allow the widest possible food product manufacture.

In 1992, 241 single plants were selected from 5 F5 lines that were originally bred and selected for adaptation to eastern Oregon. Seed from these selections was planted and evaluated in 1993; 18 F6 selections were found promising and selected for further testing in larger plots from 1994 through 1999. Through these years of breeding and selection we successfully reduced plant height, reduced plant lodging, and increased yields. Of the 18 lines, 8 were selected for further testing.

In 1999, selections from one of the advanced MES lines were made by P. Sexton at the Central Oregon Agricultural Research and Extension Center (COAREC) in Madras, Oregon to help maintain germplasm true to type. Sixteen of these selections made in Madras were chosen for further testing. In 2000, we made further selections from six of our 1992 MES lines and from OR-6 to help maintain germplasm true to type.

Starting in 2005, a new planting configuration was used. The old planting configuration had one plant row on a 22-inch bed. The new planting configuration has 3 rows on a 30-inch bed. Our objective is to provide a more uniform distribution of the plants over the soil surface. The more uniform plant distribution resulted in higher yields, perhaps due to improved access to light, nutrients, and water for individual plants. The new planting configuration retains the same seeding rate of 200,000 seeds/acre as the old configuration.

This report summarizes work done in 2007 as part of our continuing breeding and selection program to adapt soybeans to eastern Oregon and includes the added yield enhancements achieved by changing the planting configuration. Our soybean reports from the last decade are available at our station web site <http://www.cropinfo.net>. There is a search function on the home page that will conveniently find all of our recent reports dealing with soybeans by using the key word "soybean".

Materials and Methods

The 2008 trial was conducted on an Owyhee silt loam previously planted to wheat. In the spring of 2008, the field was disked twice, moldboard plowed, groundhogged twice, and bedded to 30-inch rows. On June 9, 2008, Micro-Tech® herbicide was applied at 3 lb ai/acre and the field was harrowed to incorporate it.

Five commercial cultivars, 4 older lines selected at MES through 1992, and 15 lines selected in 1999 and 2000 were evaluated; these 24 selections were arranged in 10-ft by 25-ft plots in a randomized complete block design with four replicates. The seed was planted on June 4 at 200,000 seeds/acre in 3 rows on each 30-inch bed using a plot drill with disk openers. The rows were spaced 7 inches apart (Fig. 1). Bradyrhizobium japonicum inoculant (Cell-Tech, EMD Crop BioScience, Brookfield, WI) was applied to the seed before planting. Emergence started on June 11.

The field was furrow irrigated when the soil water tension at 8-inch depth reached 50-60 centibars (cb). To understand how to irrigate using soil water tension as an irrigation criteria, see our extension brochure (Shock et al. 2005). Soil water tension was monitored by six granular matrix sensors (GMS, Watermark Soil Moisture Sensors Model 200SS, Irrometer Co., Riverside, CA) installed in the bed center at 8-inch depth. Sensors were automatically read three times a day with an AM-400 meter (Mike Hansen Co., East Wenatchee, WA).

The field was sprayed with Basagran® at 1 lb ai/acre and Volunteer® at 0.19 lb ai/acre on July 24 for weed control. For lygus bug and stinkbug control the field was sprayed with Lannate® at 0.9 lb ai/acre on July 28 andon August 11.

Plant height and reproductive stage were measured weekly for each cultivar. Prior to harvest, each plot was evaluated for lodging and seed shatter. Lodging was rated as the degree to which the plants were leaning over (0 = vertical, 10 = prostrate). The middle two beds in each four-bed plot were harvested on October 17 using a Wintersteiger Nurserymaster small-plot combine. Beans were cleaned, weighed, and a subsample was oven dried to determine moisture content. Moisture at the time of analysis was determined by oven drying at 100°C for 24 hours. Dry bean yields were corrected to 13 percent moisture. Variety lodging, yield, and seed count were compared by analysis of variance. Means separation was determined by the protected least significant difference test.

Results and Discussion

The soybeans in 2008 were planted later than in the past and emergence started on June 11, the latest since 2002. Plant height and lodging in 2008 were on average the lowest since 2005 (Tables 1 and 2). The reduced plant height and lodging in 2008 could have been due to the later emergence, shorter growth stage before flowering in early to mid-July, and fewer degree day units. Lodging has tended to be higher on average with the new planting arrangement.

Yields in 2008 ranged from 39 bu/acre for 'Lambert' to 58.9 bu/acre for '103' (Table 1). Only 'OR-8' and 'Sibley' had seed counts sufficient for the manufacturing of tofu (<2,270 seeds/lb).



Figure 1. Soybean planting configuration used in 2005-2008, Malheur Experiment Station, Oregon State University, Ontario, OR.

Summary

We have found over the years that high soybean yields can be achieved in the Treasure Valley by employing varieties selected for the environment, high planting rates, modest fertilization, use ofBradyrhizobium japonicum inoculation, proper May planting dates, appropriate irrigation, and timely control of lygus and spider mites.

References

Shock, C.C., R.J. Flock, E.B.G. Feibert, C.A. Shock, A.B. Pereira, and L.B. Jensen. 2005. Irrigation monitoring using soil water tension. Oregon State University Extension Service. EM8900 http://extension.oregonstate.edu/catalog/pdf/em/em8900.pdf


Table 1. Performance of soybean cultivars in 2008. Cultivars are ranked by yield, Malheur Experiment Station, Oregon State University, Ontario, OR.

Cultivar

Origin

Days to maturity

Days to harvest maturity

Lodging

Height

Seeds/lb

Yield



days from emergence

0-10

cm

seeds/lb

bu/acre

103

M92-085

91

98

0.0

75

2,498

58.9

M15

M92-330

96

103

0.3

75

2,521

57.3

608

M92-314

98

105

0.0

75

2,620

57.3

101

M92-085

91

98

0.3

75

2,452

57.0

312

M92-220

91

98

0.0

90

2,630

55.5

M1

M92-330

91

98

0.0

65

2,510

54.7

307

M92-220

91

98

0.0

85

2,564

54.1

107

M92-085

91

98

0.0

65

2,683

53.6

M92-085


91

98

0.0

75

2,635

53.1

106

M92-085

91

98

0.0

75

2,534

52.8

Korada


98

105

1.3

70

2,515

51.7

104

M92-085

91

98

0.0

75

2,683

51.2

108

M92-085

91

98

0.0

70

2,629

50.4

M9

M92-330

91

98

0.0

65

2,466

50.2

M16

M92-330

91

98

0.0

85

2,778

49.4

M3

M92-330

91

98

0.0

75

2,691

47.8

M92-225


91

98

0.0

75

2,669

47.5

OR-6


91

98

4.0

85

2,380

47.0

M4

M92-330

91

98

0.0

65

2,716

46.4

OR-8


98

105

8.0

65

2,120

44.6

Gnome 85


96

103

5.3

75

2,435

40.6

Evans


96

103

5.0

85

2,451

40.3

Sibley


98

105

6.0

70

2,182

40.1

Lambert


91

98

5.0

75

2,327

39.0

average


92.8

99.8

1.5

74.6

2,529

50.0

LSD (0.05)




1.9


206

12.1

Table 2. Performance of soybean varieties from 2005 to 2008. Cultivars are ranked by average yield, Malheur Experiment Station, Oregon State University, Ontario, OR.


Yield


Average 2005 - 2008

Cultivar

2005

2006

2007

2008


Yield

Days to maturity

Height

Lodging

Seed count


-------------------- bu/acre --------------------


bu/acre


cm

0-10

seeds/lb

103

73.7

72.4

64.1

58.9


67.3

93.7

92.5

4.9

2,291

107

76.6

74.2

62.5

53.6


66.7

92.7

87.5

4.3

2,343

M1

73.0

70.6

68.0

54.7


66.6

94.6

90.8

4.8

2,276

101

74.4

70.2

62.7

57.0


66.1

94.9

95.7

4.8

2,245

M15

73.9

68.4

64.8

57.3


66.1

96.4

89.7

4.9

2,296

608

70.2

68.0

66.3

57.3


65.4

95.6

93.5

5.1

2,338

Lambert

73.3

81.9

66.9

39.0


65.3

103.3

102.9

7.9

2,346

106

72.0

70.4

64.7

52.8


65.0

93.7

81.5

4.6

2,283

312

68.4

71.8

64.3

55.5


65.0

100.0

90.5

4.3

2,444

M16

69.1

69.6

69.0

49.4


64.3

94.6

98.4

4.4

2,371

M4

73.0

72.6

64.8

46.4


64.2

95.7

91.0

4.4

2,380

307

64.3

70.0

67.4

54.1


64.0

99.1

91.0

4.3

2,435

M92-085

71.9

64.4

66.5

53.1


64.0

96.7

92.6

4.9

2,318

104

70.9

66.6

67.2

51.2


64.0

94.6

92.7

4.9

2,334

M9

73.9

68.2

63.8

50.2


64.0

93.9

95.0

4.6

2,350

108

70.5

65.8

66.9

50.4


63.4

93.7

91.6

4.0

2,384

Korada

67.8

70.6

61.1

51.7


62.8

101.1

92.9

4.6

2,332

M3

69.6

72.2

61.5

47.8


62.7

95.7

98.9

4.8

2,363

Gnome 85

65.4

75.4

69.2

40.6


62.6

100.9

89.5

8.1

2,300

OR-6

65.1

72.2

62.9

47.0


61.8

95.7

100.4

7.8

2,336

Evans

69.3

71.0

66.7

40.3


61.8

101.7

92.9

8.0

2,359

M92-225

68.0

66.0

65.8

47.5


61.8

92.7

90.6

5.0

2,371

OR-8

57.8

69.6

65.8

44.6


59.4

106.1

91.2

9.0

2,120

Sibley

56.2

66.8

63.3

40.1


56.6

108.1

86.1

8.3

2,098

Average

69.5

70.3

65.3

50.0


63.8

97.3

92.5

5.5

2,321