RESPONSE OF PEANUT TO LOW RATES OF MSMA

The response of peanut to low rates of MSMA under weed-free conditions was studied in 1992 and 1994 near Tifton, GA. MSMA was applied 40, 70 , 100, or 130 days after emergence (DAE). At each application timing, MSMA was applied at 0, 90, 168, and 336 g ai ha(-1) MSMA application t iming did not affect peanut yield. Increasing rates of MSMA caused min or reduction in peanut yield. Analysis using atomic absorption spectro scopy showed elemental arsenic accumulation of less than or equal to 0 .7 ppm in peanut kernels from MSMA applied 70 and 100 DAE. This approx imates the time interval of peanut pod and kernel formation. MSMA appl ied 40 and 130 DAE resulted in little detectable arsenic in kernels. L ow rates of MSMA, originating as drift from aerial applications to cot ton or illegal and unsound applications to peanut for Florida beggarwe ed control, are not likely to reduce peanut yields. The greatest hazar d from peanut exposure to MSMA is accumulation of arsenic in kernels, which would adversely affect peanut marketability and consumer demand.