There are a bevy of cotton varieties ready for the picking for planting this season. A brief scan of varieties from Delta and Pine Land, Stoneville, FiberMax and Phytogen reveals at least 36 new offerings for 2005, says Mike Jones, Clemson University Extension cotton specialist.
He advises doing your homework, studying the data, tempering that data with local experience, spreading risks over varieties, maturity and planting dates; not over-buying technology; and the purchase of quality seed.
Jones told growers at the recent Southeast Cotton Conference that he's encouraged by data that show growers gravitating toward higher-yielding varieties over the past five years.
In 1999, only the top 10 yielding varieties in Official Variety Tests had a half percentage point of the market. In 2004, the top 10 yielders had 73.5 percent market share.
D&PL's 555BR was planted on more than 50 percent of the cotton acreage in South Carolina and Georgia in 2004. When planting this variety, Jones says, don't plant it too early, don't subject it to significant emergence challenges, and don't forget to set seed spacing. Because the variety is a full season one, don't plant it too late, don't abuse glyphosate and don't let insects take early fruit.
In most situations, apply PGRs early to D&PL 555 BR. Jones points out that the use of PGRs on cotton often results in reduced plant height and increased leaf thickness. There are questions about whether it has benefits of increased earliness, improved boll retention or increased root mass.
Jones reminded growers of Roundup Ready cotton variety issues, while looking forward to 2006 and the anticipated introduction of Roundup Ready Flex.
Roundup issues include: Sporadic problems with glyphosate tolerance; yield and quality issues; subtle yield losses due to sloppy applications; weed competition losses due to delayed applications; possible weed resistance; and weed species shifts.
Roundup Ready Flex should be available in 2006. It will allow growers to post direct applications up to 14 days before harvest. Tolerance looks outstanding, Jones says.
Flex's potential weaknesses include delayed initial application at the eighth-node stage, which could lead to poor weed coverage beneath the canopy and weeds being too large.
Monsanto officials expect 25 percent of U.S. cotton acreage to be planted Roundup Ready Flex varieties. By 2008, it's expecting 100 percent of the acreage.
The technology is undergoing a seed increase in 2005.