From Cotton Grower Magazine – June 2015
If agriculture is going to be able to overcome the problem of droughts, a good place to start would be in plant breeding.
For decades, Extension researchers were the only source of research on the topics of irrigation and water use. Luckily for American cotton producers, that has changed. Spurred on by the drive to produce cotton varieties that are superior to the competition, the cotton seed companies have invested heavily in drought research over the past decade.
For Bob Glodt—owner and operator of a small Plainview, TX, independent research firm known as Agri-Search—the sudden focus on water use has made him a remarkably popular figure. He owns a highly sophisticated research plot in Edmonton, TX. Because of his knowledge, capability and location, almost all of the major agriculture companies have approached him over the past decade about assisting them in developing varieties that display the best water-use efficiency characteristics.
“I would say we’re doing work for all the major players in cotton production on the Texas High Plains,” Glodt says. “Every company that is a major player, or has a major presence, I should say, is interested in how their varieties perform under different water regimes. The Bayers, the Monsantos, the Dow AgroSciences – all of them are interested.”
He estimates that the interest in water research trials from the companies has gone up by 100 percent over the past decade. To be sure, Glodt doesn’t handle the entirety of each company’s water research programs. But he does offer a vital service.
“The interest in water trials really began in 2006 when we started seeing a concerted effort to do some water testing,” Glodt says. “At that time, we were just kind of feeling our way along, you know, ‘How do we set up tests?’ or ‘What parameters do we look at?’ And we pretty well had it figured out by 2009.
“What it essentially boils down to is that we compare variety performance across four different irrigation regimes. One would be strictly rain-fed, and then another at 30 percent potential evapotranspiration (PET), another at 60 percent PET and another at 90 percent of PET.”
Glodt says these new parameters are significant because they assure growers that they will be able to look at how varieties respond under very specific water scenarios. This enables cotton producers to match the best-fitting varieties with their own specific on-farm water regimes.
“Once you start tying your numbers to a potential evapotranspiration level, then that data is good from year to year to year,” Glodt says, “so that’s one of the more significant things about it. So if you look at the data you can say ‘Okay, if I grow my cotton at 60 percent of PET next year, then I should be able to achieve similar results to those that are being reported.’ So it’s a good long term way to look at variety performance rather than from year to year.”
Glodt says it’s a good idea for producers to begin using potential evapotranspiration as a benchmark on their farms. In fact, the Texas Alliance of Water Conservation is encouraging growers to irrigate using PET as a parameter, because it saves water and is a more efficient way to irrigate.
One of the more significant factors evident in the midst of this research is the complete paradigm shift among the cotton seed companies in the way they market new varieties. In the past, varieties that were being introduced commercially for the first time were displayed in the showiest plots under only the best irrigation regimes. Seed companies marketed the then-new variety lines strictly in terms of their top-end yield potential. Today, that is not always the case.
“Even today, it’s hard to market a variety to a farmer and say ‘Our varieties do better at the lower water regimes’ because the mindset is all about maximum yields,” Glodt says. “And it’s still that, but there’s a qualifier – you want to produce the most you can make on the amount of water you have.
“There’s been a refinement of the way (seed companies) look at data. Some of these people at these companies were smart enough to realize that we need to be able to take the water data to the farmer.”
For growers, this sort of transparency and respect from cotton seed companies can only be a positive thing.
And water research isn’t the only tool cotton growers have at their disposal to combat the drought. There are plenty of precision agriculture techniques available to help cotton producers become more efficient and conserve as much water as possible. In fact, in response to dwindling water reserves and flagging market prices, many growers are already turning to precision irrigation techniques to help mitigate costs.
“I think part of it is cost savings,” says Tyson Raper, Extension cotton and small grain specialist with the University of Tennessee. “Part of it for several of the producers I work with in the Mid-South and Southeast is a desire to be better stewards. These guys are beginning to look at the water troubles out west, and they see the issues beginning to emerge in the Mississippi Delta with the aquifers drawing down. So they’re looking at options.”
Thankfully, Raper says there are many tools available that are easily adaptable for cotton producers. One that he mentions is known as an atmometer, and it is an inexpensive device that helps growers begin to utilize potential evapotranspiration as a parameter, as Glodt and the Texas Alliance of Water Conservation have advised.
“It is a great tool for understanding atmospheric demand and potential evapotranspiration,” he says. “That way we know how much water we’ve lost, and how much the crop may then potentially need to replenish that deficit.”
As for precision’s role in offsetting drought, Raper leaves no room for doubt.
“Precision approaches to water management allow us to combat yield reductions from drought with the least amount of water,” he says. “These instruments are something we will have to use to maximize the efficiency of our system.”