9561 Cotton Soil Fertility on Alabama Black Belt Soils

Thursday, January 8, 2009: 2:30 PM
Salon G (Marriott Rivercenter Hotel)
Charles Mitchell1, Gobena Huluka1, R.P. Yates2 and James L. Holliman3, (1)Auburn University, Auburn, AL, (2)Marengo Co. Extension System, Linden, AL, (3)Alabama Agricultural Experiment Station, Marion Junction, AL
A soil fertility experiment on Alabama Blackland prairie soils has been
conducted since 2002 in an attempt to calibrate these soils for soil
test interpretation and recommendations for N, P and K.  Weather-related
production problems have plagued this experiment since the beginning as
it has for producers on these soils.  In 2008, a high yield potential
was reduced by late-season foliar diseases which were directly related
to K fertilization rates, the first dramatic yield response to K since
the experiment began.  Surprisingly, cotton on these soils which test
"low" in P, do not respond to P fertilization.  Current P and K
calibration for cotton on these soils may need adjusting based on this