Products

Early Maturing Soybeans in Saskatchewan

Soybeans are a nontraditional crop in Saskatchewan. The earliest varieties from North Dakota and the ones which succeeded occasionally in Southern Manitoba failed badly when introduced to Saskatchewan environments. Soybeans typically like a long growing season, need higher heat units, and detest our cool evenings. Until the development of new varieties, prospects for soybeans were very poor.

The new short season varieties, which are coming on stream, have demonstrated good potential. There is still a lot to be learned.

At this point the new soybean varieties being evaluated by Terramax are demonstrating a lot of farmer friendly characteristics.

• The average yield in Saskatchewan has been 25 - 35 bu/acre on dryland.
• Irrigation produced more than 50 bu/acre.
• They are maturing in 90 to 105 days in the past three years.
• They are a legume, fixing some of their own nitrogen.
• They can be seeded and harvested with standard equipment.
• The seed is reasonably tough. It does not split as easily as peas or other bean types.
• The standability, 2.5 - 3 feet, is excellent for straight cut or swathing. Lodging and seed shattering has not been a problem.
• Solid seeding is acceptable compared to row cropping.
• Pods grow all the way to the ground. Rolling improves harvest ease.
• There is a good selection of registered chemicals for weed control.
• There are excellent industrial markets, both local and foreign, for sales.
• Yellow hilum varieties qualify for human consumption and export markets.
• Large scale production in Saskatchewan will have little effect on world markets. In the U.S. they plant in excess of 70 million acres annually.
• The current market value for soybeans, which is at a low, is $8.50 to $9.00 Canadian per bushel.

Plant Characteristics:

• Soybean - Glycine max L. .
• Upright stem, 2.5 - 3 feet tall.
• Like other legumes, soybeans can fix atmospheric nitrogen in symbiosis with a soybean-specific Rhizobium-bacteria.
• Soybeans can obtain 50 - 60% of their nitrogen needs from atmospheric nitrogen when properly inoculated.
• Cotyledons are pushed above the ground and the growing point is exposed to sunlight.
• Soybeans are known to survive only minor frosts (-2ºC) due to their exposed growing point.
• The first two leaves are unifoliate (single leaflets) occuring opposite to each other at the first node above the cotyledons. Subsequent leaves are trifoliate (three leaflets) on alternative sides along the stem.
• Flowering is triggered mainly by daylength and temperature.
• Small purple flower. Commercial soybean varieties are indeterminate - plants develop new leaves and continue growing after flowering began on the lower nodes. In a normal year 50 - 80% of the flowers fail to produce pods and as many as 50% of the pods may fail to develop seeds.
• Beans within a pod will not start growing until the pod has reached is full length.
• As the plant matures, the leaves die from the bottom of the plant up.
• Maturity is affected by planting date and growing area. Each soybean variety is given a heat unit rating based on the relative maturity of that variety, using the same crop heat unit system as for corn.
• Soybeans are rated as being mature when 95% of the pods on the plant are ripe.
• With most varieties shattering and lodging is negligible.

Seed Characteristics:

• Small seed size: ... (seed size can vary considerably from year to year).
• Yellow, brown, and black seeded varieties, with yellow being the most common type.
• Each soybean seed has a hilum which is the point where it was attached to the pod. The hilum can be either yellow, brown, gray, buff, black, or imperfect black. Yellow hilum soybeans are generally the only type accepted for the export market.
• Soybean seeds contain an average of 40% protein and 20% oil.
• Bushel weight: 60 lbs..
• Safe seed storage for one year at 13 - 14% moisture. At 12 - 13% moisture the commercial grade can be maintained for 2 - 3 years, but germination begins to decrease in the first year. At 11% moisture it can safely be stored for long periods of time, but there is a risk of mechanical damage to the seed.

Agronomic Suggestions:

• Choosing the appropriate land for growing soybeans:
  - soybeans can be produced on a broad range of well-drained soil types
  - they perform best on medium-textured soils (loam type soils)
  - heavy clay soils may lead to difficulties in planting and emergence
  - sandy or gravelly soils are least suited for soybean production
  - a lack of moisture during germination, flowering, and pod set and fill can limit soybean production
  - soybeans show a huge potential under irrigation
  - a pH of above 6.0 is recommended
  - soybeans should not be grown in the same field for more than 2 years in a row (disease problems)
  - soybeans should not follow canola, beans, or sunflowers
  - fertility requirements are high.
• Although soybeans are known to survive minor frosts, seeding should be delayed to avoid the risk of frost injury. Warmer soil (+10ºC) is required for rapid germination and emergence.
• Inoculation with proper inoculant is required. Inoculants for other legumes cannot be substituted. Follow general guidelines for inoculating pulse crops to insure a high survival rate of the rhizobium bacteria on the seed.
• Seeding depth for soybean is 1.5 - 2'' into moist soil.
• A plant population of 150 000 to 200 000 plants per acre is desirable regardless of row spacing. Seeding rate: 50 lbs./acre (small seeded varieties), 60 lbs./acre (larger seeds). Higher seeding rates can lead to drought stress in dry years. Extreme low rates may result in low pod set and excessive branching.
• Solid seeding (row spacing 15 inches or less) is acceptable and allows the use of standard equipment for seeding and harvesting.
• Roll the field before emergence to ensure good soil contact around the seed to insure quick germination and to improve harvestability.
• The seed is reasonably tough. It does not split as easily as peas or beans.
• Fungicide treatment generally does not increase yield, although it may be beneficial for older or damaged seedlots, or in fields with extreme disease pressure.
• Soybean may benefit from nitrogen application in soils with low organic matter, low pH, and low residual nitrogen. It can be applied as late as early pod fill to correct deficiency symptoms (chlorosis). Too much nitrogen causes a low nitrogen fixation rate by the rhizobium bacteria and it delays maturity.
• A 10 - 30 lbs./acre phosphate application may be beneficial in soils with very low phosphate availability. A yield increase on soils testing above 10 ppm P is unlikely.
• Fertilizer placement with the seed affects germination due to the high sensitivity of the soybean seed and should therefore be avoided. A band application 2 inches away from the seed is the most effective application.
• If potassium or sulphur fertilizer is required (soil test), it should be banded as well.
• Iron chlorosis is the most common micronutrient deficiency in soybeans (especially in soils above pH 7.4). A foliar application of iron salts can eliminate deficiency symptoms (yellow leaves with green veins). Other micronutrient deficiencies are rare, but can occur depending on local soil conditions.
• Weed control during the first weeks of the growing season is essential to maximize yield. There is a good selection of chemicals registered for weed control in soybeans (see "Guide to Crop Protection" for current information on herbicides, rates, and tank mixtures).
• Most soybean diseases have not been a serious problem in northern growing regions, but may increase with increased acreage. Common soybean diseases are White Mold (Sclerotinia stem rot), Brown Stem Rot, Powdery and Downy Mildew, Bacterial Blight, and various damping off diseases (Phytophthora Root Rot, Phytium, Rhizoctonia, etc.).
• Soybeans generally are not seriously damaged by insects in northern growing regions. Seed maggots, wireworms, grasshoppers, or mites may affect soybean seedlings and plants.
• The standability of the mature plant is excellent for straight cut or swathing. Straight combining is very common and is the most preferable way of harvesting soybeans. Operate cutter bar close to the ground, use a reel speed about 25% faster than ground speed to reduce losses, and adjust combine settings according to manufacturers specifications.
• Due to its resistance to lodging, shattering, and seed deterioration even under severe fall weather, soybeans give a very high flexibility for harvest scheduling.
• Soybeans should be harvested at 12 - 14% moisture. Where drying is available, they can be harvested at 17 - 18% moisture. Do not apply desiccant until soybean moisture is below 30% (65% of pods are brown).
• The maximum drying temperature for soybean is 60ºC (for seed 40ºC).

TOP OF PAGE

©Seedtec - Terramax
Designed by GEM Multimedia
November 24, 2003