On February 3, 2016, Monsanto announced commercial launch plans for soybean varieties resistant to dicamba and glyphosate (designated Roundup Ready 2 Xtend varieties). This announcement followed China’s decision to approve grain from these varieties for import. Many weed management practitioners hope the use of this new technology will improve control of challenging weeds, including those with evolved resistance to glyphosate and herbicides from other groups.
Integrated Crop Management News
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Corn rootworm is a persistent and economically important pest in Iowa, with yield loss caused primarily by larval feeding on corn roots. Genetically modified corn with Bt traits kills western and northern rootworm larvae, and Bt-rootworm corn has been available since 2003.
As spring plans are finalized, don’t forget to consider aerial imaging as part of a continuous improvement plan. Remote sensing and the use of aerial imagery has been used for decades in agriculture but since 2010 we’ve seen the number of available imagery providers grow extensively. The use of imagery can vary from farm to farm but several common uses include variable rate fertility recommendations, assessing water management performance, quantifying soil compaction and machinery induced yield limiters, locating late season weed outbreaks, and generally evaluating the consistency of crop vigor across a field.
This study, funded by the United Soybean Board (USB), was conducted to understand the potential for cover crops to perform in a corn and soybean rotation, and to collect data on the performance of cover crops in those rotations in relation to the timing of termination.
An earlier ICM News article discussing affects of nozzle type and size on spray coverage prompted a question from a farmer regarding nozzle selection. In recent years there have been many advances in nozzle design. The primary improvement has been development of nozzles that minimize the formation of driftable droplets (< 200 micron) while still producing a droplet spectrum that provides the level of coverage required for consistent, postemergence weed control.
Soybean cyst nematode (SCN) and soybean aphid (SBA) are important soybean pests in the north-central region. Soybean varieties with host plant resistance for SCN (PI88788) and SBA (Rag1) can suppress pest populations and subsequently protect yield. In addition, seed treatments are becoming widely adopted and now can include a nematacide, fungicides and insecticide. Combining host plant resistance with seed treatments could potentially further protect yield.
Proper herbicide application is critical to ensure products achieve their full potential for weed control. For postemergence herbicides, this includes application to appropriately sized weeds and equipping the sprayer to achieve uniform coverage of target weeds.
A farm just outside the north-central Iowa town is home to Iowa State University’s Agriculture Drainage Research and Demonstration Site, a facility that has been working to further Iowa State University’s water conservation efforts since 1990.
The first line of defense against herbicide resistance is using herbicide programs that include multiple herbicide groups effective against target weeds. When using premix products, this involves comparing the application rates of active ingredients in the premix versus rates applied with the stand-alone products. This step is needed to insure that the premix is providing an effective dose of the active ingredient.
A new study from a multidisciplinary team led by Iowa State University agronomists shows that significant portions of Iowa farmland consistently lose money and could influence many farmers to change how they use some of the acres they devote to corn and soybeans.