Goss's Wilt and Northern Corn Leaf Blight Showing Up in Iowa
Knowing the characteristics of Goss's wilt and northern corn leaf blight help in identification of the diseases; photographs illustrate those characteristics.
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Knowing the characteristics of Goss's wilt and northern corn leaf blight help in identification of the diseases; photographs illustrate those characteristics.
Carefully checking roots now for soybean cyst nematode (SCN) females can tell you if resistant soybean varieties are controlling the nematode in the field.
As adults emerge, scouting is extremely important in determining management of western bean cutworm.
By Rich Pope, Department of Plant Pathology
Iowa corn is tasseling and silking this week. We think of the silk date as a marker for the final 60 to 65 days in which the corn reaches physiological maturity. That means we might expect dry down to extend into October across the state. Soybeans are setting pods, and with timely August rainfall, pods should fill nicely. Last week we lost approximately 50 degree days to average across Iowa, making July 2009 as one of the ten coolest in history.
Weed reinfestations resulting from slow canopy development and ample soil moisture may warrant additional treatment this year.
A well-timed spray while corn leaf aphids are outside the whorl or on the tassel is recommended when they exceed thresholds.
Producers selling 2008 corn can expect closer grading and increased discount scales for damage; and they should take extra precautions to preserve the quality of 2009 crop.
Diseases currently showing up in Iowa corn - eyespot and gray leaf spot - can result in yield loss and may increase the severity of stalk rot.
Many believe that changes in corn production practices may lead to increased damage from nematodes. Mid-season sampling is required to accurately diagnose nematode problems on corn.
Learn about biology,scouting and management of corn nematodes and soybean cyst nematodes, and earn certified crop advisor CEUs in two-all day workshops.