Integrated Pest & Crop Management Newsletter University of Missouri-Columbia Vol. 16, No. 2 February 21, 2006 Aerate now that it feels like winter By Bill Casady They say a watched pot never boils and that's the strategy behind staying on top of potential storage mold and insect problems. Like a boil on your skin, a pocket of poorly conditioned grain can spoil the rest of the bin. Keep an eye on it and you can nip it in the... bin. Hot dry conditions during the late growing season have left us with a special need to be continuously cautious about stored grain. The production of aflatoxin from the growth of Aspergillus Flavus is the primary concern. Continued growth of the storage mold in the bin can lead to continued production of aflatoxin. As reports of aflatoxin hit the newswire in late December and early January, checking bins for signs of potential spoilage went to the top of our lists. Even some corn that had been supposed to be in good condition has shown some signs of the development of aflatoxin as it moved into the market. Once aflatoxin has been produced, there is no way to remove it from the grain, but with good management, we can minimize activity of Aspergillus Flavus and minimize or stop the production of aflatoxin. There was a relatively smaller opportunity to cool grain to 35 or 40 degrees F in much of Missouri before the end of the calendar year, and a warmer than normal January just didn't help much. Now that the weather has finally begun to seem a little more like winter, it is certainly beneficial to run another cooling cycle through the bin even in February. Storage molds and insects will lie dormant at temperatures close to freezing. It's important to stay on a weekly inspection schedule whenever grain has shown any signs whatsoever of less than ideal quality. Run fans at least momentarily remaining in a safe location outside the bin. The nose is one of the best tools for detecting a problem. Be careful when entering a suspicious bin. Carbon monoxide has no odor and no mercy. If possible remove a truckload or two of grain and determine if the grain has formed a characteristic cone. Never enter a bin with bridged grain. Coring the bin by removing a couple of truckloads will usually remove the most commonly encountered spoiled grain occurring at the top of the bin. Be safe. Bill Casady 573-882-4370 ********************************************************************* Soybean Rust Update By Laura Sweets The folks in the southern United States haven’t gotten much of a break from soybean rust! Scouting of kudzu and other possible hosts continued late in the year with the last report of the 2005 season being the detection of soybean rust on the last two green leaves of a one acre kudzu patch in Mobile County, Alabama, on December 21, 2005. And for the 2006 season, scouting for Phakopsora pachyrhizi, the Asian soybean rust pathogen, has already begun in the southern United States. At this time of the year most of the scouting is on kudzu and scouting is ongoing from Florida northward through Georgia and Alabama and westward to Texas. Reports of active soybean rust on kudzu have come in from Florida (11 counties), Georgia (2 counties) and Alabama (1 county). In many of these cases a large portion of the kudzu patch has been killed back by low temperatures but portions of the patch, a single vine in the patch or few a few leaves in protected areas have remained green. Scouting is concentrating on green tissue surviving in protected areas or portions of kudzu patches. The National Map Commentary at www.sbrusa.net, points out that it is unknown whether soybean rust is more widely distributed in the southern United States in early February 2006 than it was a year ago. Scouting during the last part of 2005 and the first part of 2006 has been more extensive and intensive. Results from 2006 scouting efforts are available through this Website and are being updated as detections occur in southern states. Although it is on the early side to begin scouting for soybean rust in Missouri, it is important to be aware of what is developing in the rest of the country. For 2006 it will be crucial for growers and anyone involved in soybean production to stay informed of disease development and weather patterns in the southern United States, to be aware of results from the sentinel plot system in Missouri and states close to Missouri, to scout fields and to be prepared to take prompt action if the risk of soybean rust occurring in Missouri develops. Laura Sweets Ag Ext-Plant Sciences 573-884-7307 ********************************************************************* Extension Plant Diagnostic Clinic Report -2005 By Simeon Wright In 1965, the plant diagnostic clinic was established to support county extension specialists as well as private citizens, businesses and other agencies. The clinic handles samples submitted for disease, insect, and weed identification, providing management recommendations as well. Most clinic operations are handled by clinic staff, however other Division of Plant Science Agronomy, Entomology, Horticulture, and Plant Microbiology and Pathology extension faculty handle insect and weed identification and assist when needed. Please see our website at http://soilplantlab.missouri.edu/plant/index.htm for more information about the plant diagnostic clinic, sample submission, and fees. In 2005, most samples were submitted through the mail while some were personally delivered to the clinic. A few digital photos were also submitted by e-mail. Samples were submitted from 80 Missouri counties with Boone County submitting the most samples (15 percent). Over 80 percent of the samples were received between May and September, although the clinic received samples all year. Disease diagnostic samples In 2005, a greater portion of our samples were from field crops compared with recent years. While 70 percent of field crop samples submitted were soybean, we also received corn, oats, tobacco, and wheat. The most frequent diagnosis of soybean samples included charcoal rot, Fusarium root rot and Septoria brown spot. Other soybean problems frequently submitted included frogeye leaf spot, Phytophthora root and stem rot, potassium deficiency, Rhizoctonia root and stem rot, spider mites, and sudden death syndrome. Our most common corn sample submission was potassium deficiency, and from wheat our most frequent diagnosis included Septoria leaf blotch and leaf rust. The clinic saw an increase in sample volume in 2005 over the previous year. We hope to increase this number significantly again in 2006 to better serve the people of Missouri and consequently look forward to any samples you are able to send. You are also welcome to submit insect and weed samples for identification and management information. The more samples the clinic receives, the more information we all have about the plant problems occurring in Missouri. Questions If you have any questions about fees, how to submit samples, or turn-around time see our website at: http://soilplantlab.missouri.edu/plant/index.htm. You can also contact the lab at plantclinic@missouri.edu or 573-882-3019. Simeon Wright Coordinator, Plant Diagnostic Clinic 573-882-3019 ********************************************************************** Check for Insect Problems in Stored Grain By Wayne Bailey Producers with on-farm stored grain are encouraged to check for insect and other problems in storage facilities. Bins should be inspected throughout the winter and spring seasons to determine if insect activity is present. Stored corn and wheat are most at risk for developing insect problems. Grain masses should be probed, and samples of grain placed in glass jars and inspected for insect activity after the sample grain is warmed to room temperature. If insect infestations are found, cooling the grain to 50 degrees F or less (infestations found in winter months) and/or feeding the grain to livestock are probably the best options depending on the condition of the infested grain. Cooling the grain mass to 50 degrees or less stops all insect activity and allows time to find a permanent solution to the problem. Fumigation is another option, but fumigation requires specific training, a self contained breathing apparatus, and specialized application equipment. Fumigation is best left to commercial pesticide applicators dealing specifically with stored grain insects. Wayne Bailey Ag Ext.-Plant Sciences 573-882-2838 ********************************************************************* Weather Data for the Week Ending February 14, 2006 By Pat Guinan -------------------------------------------------------------------------------- | Monthly | Growing Weekly Temperature (deg. F) |Precip (in.)|Degree Days^ -----------------------------|------------|------------ Ext- Ext- Depart| Depart|Accum Deprt Avg.Avg. reme reme from |Jan 1- from |since from Station County Max.Min. High Low Mean avg. |Jan 17 avg. |Apr 1 avg ------------------------------------------------------|------------|------------ Corning Atchison 44 18 66 11 31 +4 | 0.01 -0.43| * * St. Joseph Buchanan 43 21 63 12 32 +2 | 0.01 -0.48| * * Brunswick Chariton 43 19 65 10 31 +2 | 0.11 -0.55| * * Albany Gentry 43 16 63 6 29 +1 | 0.01 -0.54| * * Auxvasse Audrain 42 20 66 10 31 +1 | 0.09 -0.72| * * Columbia Boone 43 21 66 12 32 0 | 0.06 -0.83| * * Sanborn Field Boone 43 23 66 15 33 0 | 0.06 -0.83| * * Novelty Knox 41 18 63 11 30 +1 | 0.07 -0.46| * * Linneus Linn 43 17 65 7 30 +1 | 0.02 -0.56| * * Monroe City Monroe 41 19 64 9 30 -1 | 0.04 -0.41| * * Versailles Morgan 45 24 66 14 34 0 | 0.08 -0.7 | * * Green Ridge Pettis 44 21 64 11 32 +1 | 0.01 -0.74| * * Lamar Barton 46 20 65 12 33 -2 | 0.01 -0.82| * * Cook Station Crawford 43 18 68 8 31 -4 | 0.09 -0.93| * * Alley Spring Shannon 45 16 64 8 30 -5 | 0.07 -0.95| * * Round Spring Shannon 45 17 66 8 30 -5 | 0.04 -0.98| * * Delta Cape | | Girardeau 39 24 55 18 31 -5 | 1.52 +0.04| * * Cardwell Dunklin 41 27 56 22 34 -4 | 2.00 +0.3 | * * Clarkton Dunklin 41 25 56 19 33 -4 | 1.46 +0.14| * * Glennonville Dunklin 41 27 57 21 34 -3 | 1.49 +0.2 | * * Charleston Mississippi 40 26 58 19 33 -3 | 1.64 -0.2 | * * Portageville- | | Delta Center Pemiscot 41 28 56 23 34 -4 | 1.72 +0.18| * * Portageville- | | Lee Farm Pemiscot 41 28 58 23 34 -4 | 1.58 +0.06| * * Steele Pemiscot 42 28 55 24 34 -4 | 1.62 -0.15| * * -------------------------------------------------------------------------------- * Complete data not available for report ^Growing degree days are calculated by subtracting a 50 degree (Fahrenheit) base temperature from the average daily temperature. Thus, if the average temperature for the day is 75 degrees, then 25 growing degree days will have been accumulated. -------------------------------------------------------------------------------- Pat Guinan, Commercial Agriculture Program (573) 882-5908