By Andi Anderson
Soybean growers face a significant challenge in managing the impact of soybean cyst nematodes (SCN) on their crops. Experts emphasize the importance of collaboration between producers and their advisors, the use of resistant soybean varieties, and frequent soil sampling as key strategies to minimize SCN damage. Here's what you need to know about this critical issue:
The Prevalence of SCN: Data from BASF Agricultural Solutions reveals that SCN is widespread, with 88% of sampled fields in Michigan affected. In Michigan, the SCN threshold is approximately 4,500 eggs per 100 cubic centimeters of soil, significantly higher than the standard threshold of 500. SCN is considered the most significant pathogen in soybeans, and its economic impact is substantial, with an estimated 100 million bushels of yield loss in the U.S., equivalent to about $1.5 billion.
The Hidden Threat: One of the challenges with SCN is that its damage occurs below ground, making it difficult to detect visible symptoms in the plants. Nematodes invade the plant roots and feed on the root system, leading to poor stands, stunted plants, and yellowing foliage, among other negative outcomes.
Raising Awareness: BASF and The SCN Coalition are working to raise awareness of the dangers posed by SCN through SCN Action Month, a month-long campaign aimed at educating growers about available tools and information to address SCN issues. Currently, SCN is present in most soybean-producing counties in Michigan.
The Importance of Soil Sampling: Sampling soil is a crucial step in assessing the extent of the SCN problem. Fall is the ideal time for soil sampling. BASF data indicates that 66% of sampled Michigan fields contain damaging levels of SCN. To combat this, growers can employ Ilevo seed treatment, which can be applied to the seed before spring planting.
The Role of Rotation and Resistant Varieties: Farmers are encouraged to scout their fields regularly and rotate to resistant soybean varieties. Research suggests that rotating SCN-resistant varieties, particularly those derived from Peking and PI88788 lines, can significantly reduce SCN density. Continuous use of cultivars from a single line of resistance may still result in yield loss.
Sampling Guidelines: When collecting soil samples for SCN testing, it is important to do so just before harvest to determine maximum population levels. A minimum of eight samples of 8-inch deep cores should be collected for whole-field sampling. It's essential to send the nematode samples to the laboratory quickly and avoid exposing them to extreme temperatures. The laboratory can provide valuable information on SCN adult and cyst numbers, along with interpretations of potential yield reduction.
Considerations for Growers: Upon receiving their SCN test results, growers have crucial decisions to make. If they find high SCN numbers, they may need to consider rotating away from soybeans for a year or two. Additionally, selecting strong resistant varieties when choosing soybean varieties is a wise strategy.
Managing SCN is essential for soybean producers, and it involves a combination of vigilance, soil sampling, and crop rotation with resistant varieties. With the right strategies and awareness, growers can minimize SCN damage and protect their soybean yields.
For additional information on Soyabean Cyst Nematodes please visit the following link: https://www.farms.com/field-guide/crop-diseases/soybean-cyst-nematode.aspx
Categories: Michigan, Crops, Soybeans