Part 1, Section 6: Soybean
Soybean
Varieties
Selecting a variety for proper maturity, disease tolerance, standability, and yield performance is essential for successful soybean production. Maturity is identified by maturity groups, as described above. Figure 1.6-2 shows suggested maturity groups for each county in Pennsylvania. There is a trend in the seed industry to include a varieties relative maturity as part of its name. For example, company ABC would name a late group III as ABC 3850 whereas an early group III would be ABC 3125.
Soybean varieties are developed by state agricultural experiment stations and private industry. Performance data for many of these varieties are reported in the annual publication, Soybean Performance Report, available from county offices of Penn State Cooperative Extension. Soybean variety tests are now dominated by glyphosate tolerant or Roundup Ready varieties. In the past, there was some evidence of lower yields with the Roundup Ready varieties, but now Roundup Ready lines appear to perform as well or better than conventional varieties.
Poor-quality seed may limit yield and crop performance because of low germination, excessive foreign material, weed seed, and seed of other varieties or crops. Soybean seed is sensitive to rough handling and storage conditions. Bin run grain should not be used for seed, since most seed now is Roundup Ready varieties and saving the seed from these is illegal. Even for conventional varieties, the practice is not likely to be profitable. Studies comparing high-quality seed with bin run seed indicate that high-quality seed has an approximately 3-bushel-per-acre yield advantage. Certified seed offers the best assurance of quality. When using noncertified seed, make sure that the seed has been cleaned and that germination and purity tests have been conducted.