464 - Rhizomania Varieties Require Careful Management
A total of 25 Rhizomania resistant varieties have been approved for 2005. Only two of these varieties meet full market approval. Most of these varieties do not meet full market approval because they do not meet the sugar per ton approval criteria. These varieties provide high revenue per acre for growers, but freight will increase. Processing extensive production of beets from this type variety will require greater campaign lengths. Longer campaigns increase potential storage losses as well. What can producers do to increase sugar per ton of these varieties with little if any loss in yield?
Managing Rhizomania Varieties for Maximum On-Farm-Profit:
Dr. Joseph Giles, NDSU and Dr. Larry Smith, U of MN have conducted research with these varieties to evaluate optimum planting date, harvest date, nitrogen use and other factors. Some of these recommendations are a direct benefit of this university research.
- Plant early
- Use high plant populations
* Don't use less than 175 beets/100' is suggested
- Plant on fields with lower available nitrogen - see Table 1
* Use 20 to 40 lb/A less nitrogen
- Apply a mid-September fungicide application - do so almost regardless of cercospora level to maximize late season growth
- Harvest as late as possible certainly not before a hard killing frost
Table 1. Effect of Nitrogen Rate on Rhizomania Variety Performance in 2004.
Dr. Larry Smith, Crookston. Disease Free Location*
|Variety||Available Nitrogen (lb)||Yield (T/A)||Sucrose (%)||RST (lb)||RSA (lb)||Rev/T ($)||Rev/A ($)|
* Dr. Giles conducted a similar study at the Glyndon Rhizomania site
When available nitrogen increases from 90 to 130 lb/A (Table 1) the highly resistant variety lost no tonnage BUT % sugar decreased 0.9%, RST declined 22 lbs, RSA dropped by 510 lbs, $/T declined $4.90, and $/A dropped by $111. Decreases in yield , quality, and revenue were far less for the moderately resistant or susceptible variety. Remember this is comparative variety performance at a disease free site.
Table 2. Effect of Planting and Harvest Date on Rhizomania Variety Performance - 2004, U of MN, Larry Smith *
|Variety||Planting Date||Harvest Date||RSA (lb)||RST (lb)||Rev/A ($)|
Diploid A (Average Sugar %)
Diploid B (Low Sugar %)
* All data when available N is 130 lb/0-4 ft.
- Early planting averaged across two varieties and two harvest dates increased revenue per acre by $155.
- Late harvest averaged across two varieties and two planting dates increased revenue per acre by $235.
Educational Opportunities This Winter:
Take advantage of every opportunity to improve your on-farm-profit with new ideas.
NDSU/U of MN seminars are a must to attend
American Crystal Sugar Company Close the Gap IV Meetings. Topics to be featured in 2005:
- Precision Ag Practices for profit
- Top 50 Grower Practices Analysis for 2004
- Grower Cost Benchmarking results from 73 participants in 2004
- Production Practice Changes 1984-2004, benefits and cost savings
- Fusarium, all about the disease and its control
- Harvesting and Defoliation - Properly harvesting everything you grow
Watch your factory DTN and Internet announcements for details on meetings in January, February and March.
The International Sugarbeet Institute - March 16th, 17th:
- Visit with over 130 exhibitors
- See latest in new technology and equipment
- Update on the latest information from Washington, DC by Luther Markwart, American Sugarbeet Growers Association
Dual Magnum Use In 2005
Dual Magnum will again be available under the 24c state label program in 2005. All growers that will use Dual Magnum in 2005 must sign the 24c indemnity forms before use on sugarbeet. The forms must be signed AGAIN in 2005 even if they were signed in 2004. Agriculturists will have forms available at contracting to do this. A special thanks to the Beet Sugar Development Foundation for serving as the 24c label holding organization.