Will Tar Spot Overwinter In Northern Illinois?

Nov 06, 2015

By Russel Higgins

In earlier posts we shared that Tar spot, specifically caused by Phyllachora maydis, had been confirmed in Illinois. We are now trying to determine if the fungus will survive our winter months. A trial was established in cooperation with Dr. Santiago Mideros, University of Illinois plant pathologist. Corn leaves exhibiting Tar spot symptoms were collected and placed in mesh bags. Samples will be left both on the soil surface and buried to emulate corn residue incorporated by tillage. Next spring the samples will be collected and the survivability of the pathogen determined.

Despite the November date, our recent mild weather pattern has prevented our soil temperatures from dropping below 50 degrees. The November 4th Soil temperature measured under bare soil at the NIARC was 54.5 degrees. Current University of Illinois recommendations encourage fall applications of anhydrous ammonia to take place after the soil temperature at 4 inches reaches 50 degrees and is falling.

Source: illinois.edu

Video: Root Exudates, Soil Biology, and How Plants Recruit Microbes | Field Talk Friday

Field Talk Friday | Dr. John Murphy | Root Exudates, Soil Biology, and How Plants Recruit Microbes

Most of us spend our time managing what we can see above ground—plant height, leaf color, stand counts, and yield potential. But the deeper you dig into agronomy, the more you realize that some of the most important processes driving crop performance are happening just millimeters below the surface.

In this episode of Field Talk Friday, Dr. John Murphy continues the soil biology series by diving into one of the most fascinating topics in modern agronomy: root exudates and the role they play in shaping the microbial world around plant roots.

Roots are not passive structures simply pulling nutrients out of the soil. They are active participants in the underground ecosystem. Plants constantly release compounds into the soil—sugars, amino acids, organic acids, and other molecules—that act as both energy sources and signals for soil microbes.