Information on AUPnut

AUPnut Rules for Peanut Leaf Spot Control

The AUPnut advisory is designed to help you time your fungicide applications for control of leaf spot in peanuts. It uses the number of rain events and the 5-day forecast to stretch or shrink the time between fungicide applications. Since rain may be patchy and we have access to only a limited number of rain gauges in the peanut producing regions, you should be aware of the rules this advisory is following. You must make modifications should you get rain in your field that we do not record on our gauges. This advisory can be used in irrigated fields. Just substitute a rainfall probability of 100 on the day the irrigation will be applied and take the average of the 5-day forecast with this substitution. Note regardless of what the advisory says, apply the first fungicide application immediately if leaf spot is seen (two or more spots per plant) in the lower leaves of the plant.

The advisory is generated based on the number of "rain events" (24-hour period with more than 1/10th of an inch of rain and/or irrigation or fog beginning before 8:00PM). It also uses the 5-day average rain probability forecast and the rain forecast for each day within that 5-day average.

This is how it works...

Timing for the First Spray of the Season

From true cracking, count the number of rain events. Spray if you have counted four rain events since cracking, and the 5-day forecast calls for a 50 percent or greater chance of rain. OR, you have counted five rain events since cracking, and the 5-day forecast calls for a 40% or greater chance of rain, OR, immediately after six or more rain events.

Timing for the Second and all Later Sprays

Ten days after your last leaf spot spray, begin counting rain events and check the 5-day average forecast. The spray day is day 0, the day after, day 1, and so on. Spray if no rain event has been recorded and the average chance of rain for the next 5 days is 50% or greater. OR, One rain event has been recorded and the average chance of rain is 40 percent or greater for the next 5 days. OR, Two rain events are recorded, and the average chance of rain for the next 5 days is 20% or greater. OR, Immediately after three rain events.