
New
Production System for Cotton Yields Big ResultsBy Jim Core December 13, 2002During the past 15 years, cotton
yields in Mississippi and throughout the Cotton Belt have stagnated. The yield
plateau is generally believed to result from lack of genetic progress in
improving varieties, stress during the growing season or other unknown factors.
To overcome this problem, Bill Pettigrew, a plant physiologist with the
Agricultural Research Service's
Crop Genetics and
Production Research Unit in Stoneville, Miss., developed a production
system that could allow cotton yields in the Mid-South to resume their historic
upward trend. The key is an earlier planting schedule that boosts yields
because the plants receive more sunlight at the right time. Normally, peak cotton blooming occurs about the second week of July. By
planting earlier, growers can shift this peak blooming closer to June 21, the
longest day of the year, when potentially more sunlight is available. Also,
cotton bolls should benefit from more rainfall in June and early July than is
available later in summer. To test his system, Pettigrew planted different upland cotton varieties
during the first week of April and the first week of May from 1996 to 2000. He
compared crop growth, development, lint yield and fiber quality in early and
normal plantings. Pettigrew found plants bloomed sooner four out of five years
when planted earlier. Yield also increased 10 percent, on average, those four
years. And though an early-season cold period stunted the early-planted crop in
1997, yields from both crops were equal. His system, called the Early Planting Cotton Production System, provides
greater lint yield and avoids many late-season stresses--such as insects, high
temperatures and low moisture--while reducing the need for late-season
irrigation and insecticide application. Drawbacks could include increased risk of seedling exposure to cold stress
and increased seedling infections by soil-borne pathogens in cool and damp
conditions. However, several fungicides now available help control seedling
diseases. Pettigrew is exploring other techniques to minimize cold weather
hazards. ARS is the
U.S. Department of Agriculture's chief
scientific research agency. Story contacts Stoneville, Mississippi Crop Genetics and Production Research William T Pettigrew U.S. Department of Agriculture |