When deciding on your peanut fungicide spray program there are several factors to consider including budget, crop rotation and disease history.
As with any crop, a budget is important and with your peanut crop, it’s extremely important. These three “best management practices” that don’t cost money will also help to control costs in other budget line-items:
• Choosing the right soil type for peanuts
• Planting at the proper time
• Sticking with proper rotation. A three year rotation is minimal, but four years is preferred. Any legume crop in the rotation resets the interval back to zero.
Proper rotation mitigates disease pressure but does not negate the necessity and advantages of a fungicide spray program.
Based on several different university peanut budgets, fungicide costs are one of the top four input costs, right in line with seed costs, weed control and irrigation if you have it. Every year is different, but in all years, fungicides need to be applied as a preventative treatment and not to “cure” the infection. Unfortunately some growers, feeling pressure to cut expenses, look primarily to the fungicide line item to find savings in their budget. This can be risky. Watching every dollar is always appropriate, however, cutting the fungicide budget in the wrong way could prove to be much more costly in lost yield.
Proper use of fungicides is an important risk management tool to ensure a high yielding crop. Yields that were unheard of a few years ago are now common, thanks to the capable work of seed breeders who have brought powerful, high-yielding varieties to market. We want to avoid a situation where the potential of a variety is “bottlenecked” by implementing an outdated fungicide spray program.
Fungicide spray programs can be confusing. Every fungicide company and university has their own programs. Some are based on weather advisories and spray intervals, while others are based on disease severity and crop rotations. The truth is all of these factors are important.
It’s important to know your fields’ disease history so that you can determine the right fungicide spray program. Soil borne diseases like Southern Blight (white mold) and Sclerotina blight, caused by Sclerotina minor, can stay in fields for many years. Sclerotina has limited fungicide options. Limb and pod rot are soil borne diseases of peanut caused by Rhizoctonia minor which also attacks many other crops like tobacco, soybeans and cotton. Luckily we have more fungicide options to control limb and pod rot.
A good disease control program for peanuts starts with treated seed. All peanut seed should be treated with a fungicide to reduce seedling diseases like Cylindracladium black rot (CBR), Aspergillus crown rot, Pythium and Rhizoctonia.
In-furrow applications of Abound® can be used for additional control of Aspergillus crown rot, Pythium and Rhizoctonia. Proline® can be used for CBR suppression in fields with a history of CBR or with shorter soybean intervals in the rotation.
Foliar Disease Control
Peanuts should be scouted and weather advisories should be consulted by 30 days after planting (DAP). Foliar applications should begin at 30-45 DAP depending on weather conditions and diseases present. If you are in an area that Cadre® herbicide can be used without rotation issues to cotton, consider a tank mixture of chlorothalonil and Cadre® just to be proactive at 30 DAP. Chlorothalonil-based products include brands such as Bravo®, Echo®, Equus® and Chloronil®. This application can be considered optional in some areas.
If no fungicide application is needed at 30 DAP, you must start your foliar disease program by 45 DAP. There are many very good fungicides available for this timing. Again the best fungicide program is one that prevents diseases from even getting started. Fungicide choices at 45, 60, 75 and 90 DAP include products that deliver foliar and soil borne disease control such as Abound®, Alto®, Provost® and Fontelis®. Chlorothalonil-based products can be tank mixed with these products for additional disease control and resistance management. Omega® and Fontelis® are your best options for Sclerotina blight. Never end your spray program with a solo application of Abound® or similar fungicide to help reduce the potential for disease resistance.
As always, consult your Coastal AgroBusiness representative to discuss the best peanut fungicide program tailored for your farm.
Information provided by Coastal AgroBusiness, Inc.
Abound, Alto, Bravo, Omega and Chloronil are registered trademarks of Syngenta Crop Group.
Proline and Provost are registered trademarks of Bayer Crop Science.
Fontelis is a registered trademark of E. I. duPont de Nemours and Company.
Echo is a registered trademark and manufactured for SipcamAgro USA Inc.
Equus is a registered trademark of MANA, Inc.
Cadre is a registered trademark of BASF Corp.