• B.S., (1970) Crop Science, University of Arkansas.
• M.S., (1974) Plant Breeding, University of Arkansas.
• Ph.D., (1978) Genetics, Texas A&M University.
• Cotton Breeder, (1978-88 ) Mississippi State University.
• Cotton Breeder, (1988-present) University of Arkansas.
• Center Director, (1997-present), Northeast Research& Extension Center, Keiser, Ark.
Choosing the best cotton variety can be a daunting task. Some years ago, a young cotton producer cornered me after I had made a presentation at a county production meeting. He wanted to know more details about two specific varieties. I carefully and painstakingly explained to him every possible difference in the two closely related varieties and indicated that both were good varieties. He continued to press me to choose one for him. Finally, I suggested that he plant both and compare them. He replied, “I can’t do that since I only need one bag to plant my five acres of cotton.”
Most producers are more flexible than this young farmer but choosing the best variety for a field is just as critical and can make a big difference at the end of the year. The yield difference between the highest and lowest yielding varieties in the 2010 Arkansas Cotton Variety Test was about 500 pounds of lint. Seed costs, technology fees and other production costs for the two varieties would have been similar. Thus, the difference in yield would translate directly to variation in profits, less the higher harvest and ginning costs. (I never have known anyone to complain about increased harvest and gin costs associated with higher yields!).
The landscape of Mid-South cotton varieties dramatically changed in the late 1970s. For several years, more than 90 percent of Mid-South cotton had been planted to two varieties, Stoneville 213 and Deltapine 16. The dominance of the two varieties was broken by the release of two short-season, public varieties – DES 24 and DES 56. Additional short-season varieties from private companies soon became available. Compared to full-season varieties, these short-season varieties produced equal or greater yield with lower vulnerability to late-season pests and adverse weather.
A second major varietal landscape change occurred in the 1990s with the introduction of transgenic varieties. Transgenic cotton in Arkansas increased from less than one percent of acreage in 1995 to more than 99 percent in 2004. Similar shifts occurred in most states. Varieties having one transgene (BXN, Bt, or Roundup Ready) were soon replaced by varieties with stacked gene technology. More recently, varieties having additional constructs of Bt (Bollgard II and WideStrike), Roundup Ready Flex, and/or LibertyLink technologies have been released. In 2010, 97 percent of Arkansas cotton was planted to B2RF and WRF varieties.
A third landscape shift may now be occurring in some areas. Wide use of glyphosate on several Roundup Ready crops has led to development of resistance to glyphosate in several weed species, most notably pigweed. Consequently, other herbicides must be used in combination with glyphosate to obtain satisfactory weed control. At the same time, newly developed insecticides can provide worm control comparable to Bollgard II and WideStrike.
These changes have engendered attention to other herbicide-resistant transgenes and have renewed interest in conventional varieties. To meet the latter need, the University of Arkansas is currently releasing three conventional cotton varieties – UA48, UA103 and UA222. All three produce competitive yields, are early maturing, resistant to bacterial blight and have improved fiber quality. UA48 has been licensed to Americot, while UA103 and UA222 are licensed to Seed Source Genetics.
Other public institutions are also currently releasing some outstanding conventional varieties. I do not expect a major shift to conventional varieties to occur. But these public varieties do provide cotton producers another choice and will likely be an effective alternative in some areas.
Since specific transgene combinations have major effects on the whole production system, first determine what transgene combination is desired. Then compare yield and performance history of candidate varieties. Yields over multiple years from nearby test sites with similar soils are best, but data are limited. Programs such as COTVAR can assist with comparing yield. Pay attention to pest resistance and variety maturity. Finally, among the best yielding varieties, give priority to the ones having the best fiber quality.
Having worked in cotton breeding and variety testing since 1970, I have had the opportunity to witness all of these landscape changes. It is hard to imagine how the landscape may change in the future.
Fred Bourland is professor at the University of Arkansas and director of the Northeast Research and Extension Center in Keiser, Ark. Contact him at email@example.com or ((870) 526-2199.