Pointers Never Leave Peanuts Unprotected July brings a series of decisions that are generally associated with disease management. While herbicides will need to be applied in some fields and there could be outbreaks of foliar-feeding insects (hopefully not spider mites), the key to optimizing yield will be timely applications of effective fungicides. Starting DAVID JORDAN North Carolina State fungicide sprays at the R3 University stage of peanut development Extension Agronomist is the general recommendation in the Virginia-Carolina region. With the exception of fungicide programs that include Miravis with either Elatus or Convoy for stem rot control, applying fungicides every two weeks, as long as conditions are favorable for pathogens, is critical. When weather is not favorable for leaf spot to develop, which can be determined using local weather-based advisories, stretching out the days between sprays can reduce expenses and minimize the likelihood of spider mite outbreaks without sacrificing leaf spot control. Never leave peanuts unprotected when conditions are favorable for pathogen development and incidence of disease. When fungicides are applied in a timely manner and in a way that should keep peanuts protected, remember to select the correct fungicide to do the job at hand. With leaf spot resistance present for several fungicide sites of action, making sure effective fungicides or mixtures of fungicides are applied can make all the difference. Check with your local Extension agent or specialist to know what levels of resistance might be present in your area and formulate a fungicide program accordingly. In July, Apogee or Kudos is applied. These products prevent internode elongation and minimize growth. Two applications are generally needed. The first goes out at 50% row closure where half of the vines from adjacent rows are touching. The follow-up spray goes out two to three weeks later depending upon regrowth and weather conditions. Don’t be early on the first spray, and make sure nitrogen is included with the application. While increases in yield and grade can be inconsistent, there are more intangible benefits to using these products. Digging can be easier when rows are more clearly defined, and as peanut plants move through the digger, there is less loss of pods. Vines invert more easily and stay in windows (falling over) more often when these products are applied, especially for peanut varieties that have a vigorous growth 20 /
THE PEANUT GROWER • JULY 2020
habit, also considered rank growth. Much of what happens in July and August is setting us up for flexibility and efficiency in digging and harvesting peanut. Actions now determine the flexibility you will have in September and October. Increased f lexibility means greater ability to optimize yield and financial return, especially with the unpredictable nature of weather.
Apply Fungicides Preventatively Disease and insect management will be important as we move into the second half of the growing season. It is highly encouraged to scout fields on a weekly basis even if you believe you are in the good fungicide program. We observed mite infestations in several fields in the west EMI KIMURA Texas during 2019 growing Texas A&M AgriLife season. Although it is not a common issue, environmen- Extension Peanut Specialist tal conditions were favorable for mite populations. Without careful scouting of fields, such problems can be easily ignored. They will reduce yield potential if they are not treated immediately. In the Southwest, the common diseases affecting peanuts are the pod rots, leaf spot and Sclerotinia blight. Research compared fungicide applications between preventative calendar-based applications 60 to 70 days after planting and PEANUTGROWER.COM
