Soybeans: Variety Selection

| Corn | Soybeans | Forages | Cereals | Dry Edible Beans |
| Spring and Winter Canola | Other Crops | Soil Management |
| Soil Fertility and Nutrient Use | Field Scouting |
| On-Farm Stored Grain Management | Weed Control |
| Insects and Pests of Field Crops | Diseases of Field Crops | Appendices |

Pub 811: Agronomy Guide > Soybeans > Variety Selection

Order OMAFRA Publication 811: Agronomy Guide for Field Crops

There are over 200 soybean varieties, and their turnover in the marketplace is relatively quick. Aside from maturity and yield, base variety selection on resistance or tolerance to disease, aphids, standability and soybean cyst nematode resistance.

Maturity and CHUs

Soybean development is affected by heat unit accumulation, day-length and hours of sunshine. Disease, moisture stress and other stresses can lengthen or shorten the actual days to maturity, depending on when the stress occurs.
Select a variety that corresponds to the heat unit rating for the area. Figure 1-1, Crop Heat Units (CHU-M1) Available for Corn Production,shows approximate CHUs for Ontario. Selecting full-season varieties will make maximum use of the growing season and offer the opportunity to maximize yield. When growing specialty soybeans, such as the white hilum types, selecting shorter-season varieties will help ensure quality at harvest.

Hilum Colour

The hilum is the point at which the soybean seed attaches to the pod. Varieties differ in hilum colour and can be yellow (Y), imperfect yellow (IY), grey (GR), buff (BF), brown (BR), black (BL) or imperfect black (IBL). Yellow hilum soybeans are generally the preferred type for the export market. Hilum discolouration may occur on the imperfect yellow (IY) varieties. Affected beans may not be acceptable for export markets.

Choosing Superior Varieties

In addition to maturity rating, other important factors for choosing varieties are:

• yield potential
• standability
• insect and disease resistance

In selecting superior varieties, three main sources of information exist:

• performance trial data
• on-farm strip trial data
• company information on characteristics of a variety

The Ontario Oil and Protein Seed Crop Committee conduct performance trials each year at various locations across the province. Results are published each fall in the Ontario Soybean Variety Trials brochure. This brochure is available on the Internet at www.gosoy.ca. These trials are valuable for comparing the yield potential of varieties as well as providing ratings for maturity, plant height and lodging. In Southwestern Ontario, at locations with clay soil types, varieties are evaluated for resistance to phytophthora root rot. Varieties with resistance to phytophthora root rot are recommended on heavier soils. In fields with soybean cyst nematodes (SCN), include varieties with SCN resistance regularly in the rotation (see Soybean Cyst Nematode).

Seed companies will provide detailed information on growth characteristics of varieties to aid in selection. When evaluating variety performance, take into account that variety trials conducted under conventional tillage have proven to be a reliable indicator of a variety's performance under no-till conditions.

Plant fields on medium-to-light-textured soils and fields that have regular manure application or high residual nitrogen levels to a variety with reduced lodging potential. If the soybeans are intended for on-farm livestock feed, choose a variety with a high protein index.

Individual varieties may perform differently depending on growing conditions. Grow more than one variety to reduce the risk of crop failure. Plant the majority of the acreage to proven varieties while testing new varieties on a smaller scale.

Identity-Preserved (IP) Varieties

Identity preservation is the segregation of a variety from planting through to delivery to an end user. It is not a new concept but has existed in a number of markets, including seed production and the production of food-grade soybeans. The introduction of GMO crop varieties has resulted in consumer demand for identity-preserved, non-GMO soybeans. The market offers various levels of premiums and contracts to the grower.

The premiums offered for producing IP varieties must be weighed against their increased costs, time and management. Limit the acreage planted to a size that can be harvested in a timely fashion. Performance information for some specialty-trait varieties may not be available. Data for these varieties may only be available from the company selling the seed and/or agreeing to take delivery of the crop after harvest. The agronomic qualities of an IP variety, such as yield, disease resistance and maturity should be evaluated to determine whether or not the premium offered upon sale is adequate. Performance trials of a number of food-grade soybeans are conducted by the Ontario Oil and Protein Seed Crop Committee. This information is available on the Ontario Oil and Protein Seed Crop Committee website at www.gosoy.ca. For crop insurance purposes, Agricorp provides a yield adjustment factor for a number of specialty soybeans.

Biotechnology

Varieties carrying special traits, such as resistance to certain herbicides, are available in Ontario. These may have value for growers trying to address specific weed problems. They can also be useful in certain tillage systems. These varieties may not be accepted in all soybean markets.