Variety Shifts Cause Potassium On Cotton and Calcium On Peanut Recommendations to Be Confirmed.

Both cotton and peanut acres in Georgia in the last ten years or so have been dominated by a single variety.  In just the last few years, acreage of these dominant varieties has been reduced dramatically and shifted to a number of new varieties.  In the case of cotton, most of the new varieties are not only high-yielding, but earlier fruiting and faster fruiting types compared to the old standard.  This has created concern that the current recommendations for potassium rates and management may not work for the new varieties.  In the case of peanut, the old dominant variety was a small-seeded runner type and the most of the new varieties are large-seeded runners.  This has created concern that the current recommendations for calcium rates and management may not work for the new varieties.  Field experiments were conducted in 2009 to address this issue on both crops.  Based on this data, it appears that the current recommendations for both potassium on cotton and calcium on peanut are sufficient.