When it comes to SCN (SOYBEAN CYST NEMATODE) resistance in soybean varieties, THE PI 88788 SOURCE HAS BEEN THE GOLD STANDARD FOR DECADES.

It is well-documented that tolerance/resistance to that protection is developing and more SCN reproduction on plants with PI 88788 is occurring.

The other SCN resistance source available in current soybean varieties, PEKING (PI 548402), is growing in popularity.

However, Peking has been available to soybean breeders for even longer than PI 88788. In fact, the Peking varieties had a significant yield drag compared to PI 88788 varieties up until recent years. Now, there are plenty of trials where the Peking varieties are finally winning, likely due to better SCN protection. However, don’t assume that just because your seed has Peking, it will be a superior variety for yield. It’s the same thing we say with corn rootworm Bt hybrids – that yield is a function of good germplasm AND an effective trait. Even with a great trait, poor germplasm can cost you yield.

That’s not to say that Peking varieties come in poor germplasm anymore. It’s just advice not to pick a variety simply because it has Peking.

One watchout with the Peking varieties is that this source of SCN resistance involves multiple genes to provide the best possible SCN protection. Some varieties on the market are claiming Peking resistance and only have two of the three genes. Talk to your seed provider and watch the trials done by third parties in SCN-infested fields to learn which varieties are providing the best level of protection. In the Hefty Brand lineup and in the Zinesto soybean lineup, all Peking varieties except one, Z2005, have all three genes. We made an exception on Z2005 due to elite germplasm with very good performance on white mold, phytophthora, and brown stem rot.

BEST PRACTICES TO MANAGE SCN

  • 1

    TEST PROBLEM AREAS IN YOUR FIELDS. You can often identify the worst SCN spots by finding poor-yielding zones. Soil sample pulling 6” cores in the row of soybean plants. Unlike normal soil samples for nutrient content, SCN samples are generally sent in plastic bags to avoid drying down and potentially damaging the nematodes. Re-testing every 6 years is recommended.

  • 2

    ROTATE SOURCES OF SCN RESISTANCE TO KEEP THEM EFFECTIVE. You may choose a Peking this year but find a PI 88788 the next time soybeans go in that field. Consider the Nemasphere trait (which contains the industry’s first Bt for SCN control) when varieties become available and are worthy of a spot on your farm.

  • 3

    USE A TREATMENT WITH SCN CONTROL. Seed treatments are not amazing on SCN, but they can sure help a little. My favorite right now is the relatively new product, Victrato. Of all the seed treatments we’ve tested, it’s been the best on SDS (sudden death syndrome) control, plant health, and SCN suppression. Also, look for natural products that can add another mode of action.

  • 4

    ROTATE TO NON-HOST CROPS. Sure, a corn-soybean rotation helps, but if you plant corn for 2 or 3 years before going back to soybeans, you’ll see even more advantage. On our farm, we’ve brought alfalfa back into our rotation to get 4+ years away from SCN and corn rootworms.