Shedding More Light on Cotton Increases Yields
By Tara Weaver
December 12, 1997
Planting Midsouth cotton a month earlier to shift the peak flowering
period yields more cotton bolls and fiber, a recent
Agricultural Research Service
study suggests.
ARS scientists at the
Cotton
Physiology and Genetics Research Unit in Stoneville, Miss.,
investigated earlier planting times because cotton in the Midsouth
region in particular suffers from insufficient sunlight or light
deficiency. The region includes Mississippi, Arkansas, Louisiana and
western Tennessee.
In the first year of a multi-year field study, the ARS scientists
planted cotton during the first week of April, a month earlier than
usual. This ultra early planting shifts the peak flowering
period closer to the summer solstice--the longest daylight
period--when plants can soak up more light.
Ultra-early-planted cotton produced 11 percent more fiber, known as
lint, than cotton planted at the normal time.
Cotton planted in April also flowered approximately 2 weeks earlier
than the other crop. This would let growers harvest and get the crop
to market earlier. Prices are higher then because available supplies
are lower. Another advantage of early maturity: Growers can avoid the
greater insect pressures that occur later in the season.
One disadvantage to ultra-early planting is that some plants may
suffer early-season cold stress. But studies so far show that, even if
the plants are cold-stressed, yields can be about the same as for
normal planting. The scientists are trying to identify more cold-
tolerant varieties.
Scientific contact:William T. Pettigrew,
Cotton
Physiology and Genetics Research Unit, Stoneville, Miss., phone
(601) 686-5234, fax 686-5218, bpettigr@ag.gov.
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