There's little doubt that PM 1218 BG/RR cotton variety is still king in west Tennessee, since it's planted on over 80 percent of the cotton acres there. But it never hurts for farmers to keep their eyes and ears open for new cotton cultivars, technologies and production methods.

That's why Craig Massey, University of Tennessee Extension area specialist, plant and pest management, Chism Craig, Extension cotton specialist, and Scott Stewart, UT cotton insect specialist, planted a dozen large, on-farm test plots this spring comparing 17 new cotton varieties with the old standby.

Like any variety, PM 1218 BG/RR has its downside — the variety trends close to the discount range for micronaire. But its high yield and early maturity are traits that growers in west Tennessee love.

Massey is less concerned about high mike in the variety than he is with the fact that so much of it is planted there. The problem? “When 1218 comes off, it's ready to go. We need to pick it. But we can't always pick it all at the same time.”

So Massey has included varieties in the test that run the gamut of maturity — 12 are early- to mid-maturity varieties (including DP 444 BG/RR, ST 4892 BR, SG 501 BR, DP 451 B/RR, FM 960 BR and ST 4793 RR) and five are mid- to full-maturity varieties (including DP 555 BG/RR, ST 5599 BR, ST 5303 R, FM 991 BR and FM 989 BR).

On a 26-acre, silt loam field near Somerville, Tenn., Massey takes the testing a step further, not only comparing each of the new varieties, but looking at each of them side-by-side in ultra-narrow-row (10-inches) and wide-row configurations.

On a recent day in mid-June, almost all the varieties on the UNR side of the plot had canopied. The wide-row side will require at least two more directed spray applications of a herbicide.

Massey is also comparing Liberty Link/FiberMax cotton varieties with Roundup Ready varieties, which includes a look at how each is affected by drift from the other herbicide.

Massey hopes to give growers a complete set of data from yield to fiber quality to economics for all of the varieties.

Questions that could be answered include:

Is UNR an option for late-planted cotton? And what varieties work best? Massey noted that the last two years have brought late plantings and lot of replant situations in west Tennessee. Growers need more information on what works and what doesn't works in these situations.

While the 2003 planting window ran over 45 days, from April 15 to June 1, the normal window for planting in west Tennessee is seven to 10 days given favorable weather. “The reason we're looking at these mid- to full-season varieties is to space that window out,” Massey said.

At the same time, the wider planting window in 2003 should shed some light on how varieties perform under a wide range of planting dates, according to Massey. “Last year, some June 5 cotton outyielded April- and May-planted cotton. That was a bit of a fluke because we didn't have an early frost. But we have a lot of variables to look at in these demonstrations.”


e-mail: erobinson@primediabusiness.com