Five Keys to Higher Cotton Yields
It’s said that a corn grower can only lose yield after planting, but a cotton producer can push yields from pre-plant through harvest. As growers in the majority of the Southern Cotton Belt begin shifting their planting focus to cotton, they should consider five optimum pre- and early season opportunities to manage for top yields: variety selection, nematode management, seeding rate, and weed and thrips control.
Seek Varieties with High Seedling Vigor
It’s not too late for growers to look for cottonseed varieties that have a reputation for seedling vigor and have consistently ranked high in university and on-farm variety trials over multiple years.
“Residual herbicides, which are once again standard practice for cotton, impose a significant stress on young seedlings,” said PhytoGen Cotton Development Specialist (CDS) Steve Brown. “It is important to have a variety that routinely can withstand this stress, and those varieties with excellent seedling vigor provide a clear advantage in stand establishment and early season growth.”
Count the Ways to Control Nematodes
The continuing outcry over the loss of Temik three years ago forces growers to seek alternatives to control nematodes, including crop rotation, soil fumigants like Telone, new root knot nematode-resistant varieties, seed treatments and post-emergence foliar nematicides.
Which nematode management tool a grower chooses should be based on soil sample results and field history.
More Seed Isn’t Always Better
Many growers know how low they can go on seeding rate. But the rainy experiences from 2013 and the cool start to the 2014 season may have many considering a higher rate to counter Mother Nature.
“I don’t like thick stands,” Brown offered. “And that applies to both hill dropping and even spacing. What looks perfect in May can seem too crowded in August. I like to see thick-stalked, strong plants – not spindly ones.”
Brown favors a rate of at least two seeds per foot. A limited amount of current research suggests populations below 1.5 plants per foot may have a negative impact on yield.
Joel Faircloth, PhytoGen CDS for the Carolinas and Virginia, generally recommends planting about 35,000 to 42,000 seeds per acre – “lower in South Carolina and increasing as you move north.”
“Low seeding rates make each plant responsible for a larger portion of the crop,” pointed out Russell Nuti, PhytoGen CDS for the Lower Southeast. “In regions with a shorter growing season, a higher population should enhance earliness as long as the rate is not high enough to cause excess vegetative growth. “
Win the War on Weeds
The key in early season is to control anything that might slow down that seedling. Weeds are key competitors and pose a bigger threat than the stunting effects of preplant residual herbicides.
“If the plant is growing poorly, growers often choose to delay post herbicide applications for fear of further crop injury, particularly tank mixtures of burndown products and residual herbicides,” Brown says. “Such a delay can be disastrous in the presence of Palmer amaranth. It’s a bad thing when poor seedling growth limits postemergence weed control.”
Trip Up Thrips
Growers who choose a high-vigor variety, control nematodes and eliminate competition from weeds can minimize thrips damage.
“Research indicates that a cotton seedling is past the stage where thrips can cause economic injury at the four-leaf stage. A more vigorous plant can reach that stage quicker,” said Faircloth. “Protecting the plant from thrips injury up to the four-leaf stage in the Carolinas and Virginia is critical, and an overspray is required to avoid maturity delays and potential yield loss.
“Also, it is worth noting that thrips alone don’t typically cause yield loss,” he added. “It is a combination of thrips and other factors like cold temps, moisture, sand blasting, seedling disease, and/or herbicide injury. A more vigorous plant should be less susceptible to and should recover quicker from these factors.”
Seizing the potential of a cotton crop requires more intense early season management early season than it once did, but high yields are the reward for the grower’s time and effort.
“In the early magic of the Roundup Ready era, it was amazing to watch cotton grow off so rapidly, largely because we weren’t using preemergence herbicides. Those days are gone,” Brown says. “Strong seedling vigor can help cotton grow through these challenges.”
Source – PhytoGen