2024 Variety Selection

ARIZONA | Randy Norton

During the cool winter months, with the crop harvested and out of the field, it is a good time to review the previous year and  make plans for the upcoming season, which will be upon us in no time. One significant area to consider is your fertility program. Evaluating what you did in 2023 and making plans for the 2024 season with respect to your fertilizer program can potentially reduce costs, improve efficiencies and hopefully result in a healthier bottom line for your operation.

With input costs, including fertilizers, at high levels, scrutinizing all inputs for positive return on investment is critical. The goal is to provide sufficient nutrients to maximize productivity, but not to excess. Conversely, the last thing we want to do is compromise productivity by cutting fertilizer rates to the point where we are not supplying what the crop needs, given the production scenario. The University of Arizona Cooperative Extension has developed many tools and guidelines over the years to assist in making these decisions. Many of these recommendations and guidelines can be found on our website at extension.arizona.edu/crops-soils.

Regular soil testing should be a part of an effective crop and soil fertility program. Annual testing of soils may not be a requirement. Occasional testing, perhaps every other year, is recommended to provide information to help adjust and fine-tune your fertility program. Soil testing is more critical for some nutrients than for others. In most desert soils found in the cotton-producing regions of Arizona, potassium (K) is often found in sufficient quantities for crop production. Soil test levels above 150 ppm (ammonium acetate extraction) typically provide enough K for a cotton crop not to experience a deficiency. Soil test levels of phosphorus (P) above 5 ppm (Olsen — sodium bicarbonate extractable P) are sufficient for cotton production in Arizona. Nitrogen (N) is more complex because of the dynamic nature of that nutrient in the soil ecosystem. Nitrogen is subject to various transformations, which can render it either available or unavailable to the cotton crop. Other nutrients can undergo similar changes but less readily than N in our desert soil systems.

To learn more about the dynamic nature of N and how to manage that nutrient in our cotton production systems effectively, go to our website (mentioned above) or reach out to your local Cooperative Extension personnel. Efficient management of nutrients in our production systems is important from an environmental and economic perspective. rnorton@cals.arizona.edu

TEXAS | Ben McKnight

As the 2023 season winds down in Texas, growers are already making plans for the 2024 cotton crop. Perhaps the most important decision growers will make about next year’s crop is the varieties they will plant and manage for the remainder of the season. With so many varieties to choose from, this decision is not necessarily an easy one to make. Fortunately, there are resources available to growers that will provide useful information to consider when making their decision on varieties to plant.

The Texas A&M AgriLife Extension Service annually conducts several cotton variety trials across the cotton-producing regions of the state. All of these regional RACE trial results can be found at https://varietytesting.tamu.edu/cotton/. By the time you are reading this in the new year, results from 2023 cotton variety testing will begin to be published at this link. I encourage growers to look at the previous year’s results to assist with variety decision-making for the upcoming year.

It seems the weather conditions in 2023 were very similar to the conditions experienced in 2022. Hot, dry weather prevailed across much of the state for a good portion of the growing season, and many of the variety trials in 2023 were impacted by drought. While results from 2023 may highlight varieties that performed better in drought conditions, I always encourage growers to look at results from previous years to gauge variety performance over multiple years and different weather conditions.

Lastly, there are many different trait packages available in commercial cotton varieties. Consider some of the most yield-limiting factors on your farm and weigh the benefits that certain traits may bring to the table. For example, if nematode pressure is a yield-limiting factor on your farm, there are now several nematode-resistant commercial varieties that may be a suitable variety for your operation. If bacterial blight is a yield-limiting factor, the first consideration of variety selection should be bacterial blight resistance. bmcknight@tamu.edu

MISSOURI | Bradley Wilson

Variety selection is one of the most important decisions to properly prepare for the upcoming growing season. Choosing varieties can be difficult due to the wide selection of choices available and various soil types they are planted into. Varieties can behave differently when planted into differing soil types; therefore, knowing the soil types in each field can help you narrow down selection of varieties that are known to perform in that environment.

Management style can also change variety behavior. Some cotton cultivars are inherently more aggressive than others. Knowing this varietal information can help you choose a cultivar based on your typical style of growth management and water scheduling during the season.

Pest management is also a key reason to evaluate cotton variety selection. If nematodes or diseases have been present in fields in previous years, it may pay off if we select tolerant or resistant varieties to plant in these environments.

The last issue to cover is planting in a short-season environment; therefore, choosing early to mid-maturing cultivars can protect us from late-season issues such as an early frost that can impact cotton yield and leaf grade of mature fiber.

The University of Missouri Cotton OVT data for 2023 can be found at https://moaes.missouri.edu/t-e-jake-fisher-delta-research-extension-and-education-center/ under the variety testing tab. Three locations were planted in 2023 including Portageville (Silt loam), Clarkton (Sandy loam) and Senath (Silt Loam). brwilson@missouri.edu

MISSISSIPPI | Brian Pieralisi

Variety selection is a difficult decision. It is just as important as it was last year, and possibly more important moving into 2024. Considering varietal placement for your region or agronomic practices, plus disease packages and herbicide technology, influences overall management for the entire season. Not to mention, improper variety placement can cost you up to 200 or more pounds of lint per acre.

By the time you read this, 2023 cotton variety performance data for both MSU small plot and on-farm trials will be posted to mississippi-crops.com. At this point, some of the newer varieties have had two or three years of performance history, which helps in making selection decisions. Mississippi State small plot variety trials have evaluated approximately 40 varieties for the past two years over nine locations, two regions and irrigation practices. I recommend selecting a similar environment in the small plot trials to where you are placing a variety and comparing these varieties to a similar environment in a large plot situation. Finding a variety with two or more years of performance data is also important in strengthening your decision. Two-year performance data is available for both Hill and Delta regions in the MSU small plot variety trial publication.

In 2023, our variety trials contained ThryvOn technology. This was our first year testing these varieties in our official variety trials. I suspect we will see more and more acres planted in new technologies. Again, pay attention to performance of these varieties in the Mississippi State cotton publications. Lastly, reniform nematode-tolerant varieties are an excellent way to minimize yield reductions in the presence of high nematode infestations. In Coahoma County, our nematode tolerant varieties produced 200-300 pounds more lint per acre than the top-performing, nontolerant varieties.

Happy New Year! bkp4@msstate.edu

ALABAMA | Steve M. Brown

Row spacing has generated attention in recent years. Because wide row patterns tend to sacrifice yields compared to standard rows, 72-inch, and probably 60-inch, solid-planted rows are too wide for peak production. Our research demonstrated equivalent yields with 48-inch, solid-planted rows compared to standard 36-inch rows at two south Alabama locations over three years, with some yearly variation.

Obviously, alternative row patterns must fit the overall farm operation. Akin to that is the ease of exploring different row configurations with existing equipment; hence, using a 36-inch row planter to evaluate 72-inch rows and a 30-inch planter for 60-inch comparisons.

Motives for wide row patterns include reduced seed costs, improved mid-season stress tolerance, reduced late-season hardlock and boll rot and lower picker costs. The first point assumes the same seeding rate down the row for both novel and standard-row widths. The last idea presumes a lower cost of picking since each pass will cover a slightly wider area. Admittedly, some of these benefits have not been thoroughly studied.

I don’t see anyone switching to 48-inch-row cotton, though I think it could work. There are other ways to move in that direction.

Compared to a standard 36-inch row planter, widening to 40-inch row spacing or using a 20-inch grain planter and voiding alternate rows can provide an 11% cost savings if the same down-the-row seeding rate is maintained. While solid 30-inch rows incur additional costs for planter, seed and picker, a 30-inch by 60-inch skip row pattern (two 30-inch rows with a 60-inch skip) provides an effective row width of 45-inches, and each is an “outside” row. Again, this latter system accommodates grain crop production with its narrower rows.

A few farms in north Alabama employ the row configurations mentioned above. I’m familiar with one that plants the 30-inch by 60-inch skip row pattern at two seeds per foot, a population of about 23,000 seeds per acre. They extended the tool bar slightly to center the outside picker heads 18.3 feet apart as opposed to 15 or 16.7 feet for 36-inch or 40-inch rows, respectively. They consistently pick excellent cotton. cottonbrown@auburn.edu

GEORGIA | Camp Hand

When it’s time to start thinking about variety selection in cotton, many will say “don’t put all your eggs in one basket.” As someone with laying hens, this saying doesn’t make much sense to me. However, when it comes to variety selection, I think it is very fitting.

As variety trial results are pouring in from county agents, this saying gains greater meaning. One of the varieties that performed extremely well in Georgia the past three to four years was a little more hit or miss in 2023. Meanwhile, the varieties that have been in the second-highest-yielding group (or lower) have risen to the top. This is the first year since I started that we have had a great August/September, and we had minimal boll rot, which I think has contributed to what we are seeing this year. However, this is a prime example of why we always recommend spreading your risk by planting multiple varieties.

Of course, variety trial data from universities, independent consultants and industry are plentiful. The two resources we provide at the University of Georgia are the on-farm variety trial program and the OVTs. The on-farm variety trial program in 2023 evaluated 10 varieties across nearly 25 locations throughout our state, giving us a great idea of how these varieties performed across a variety of production environments. Results for the on-farm program can be found at ugacotton.com. The OVTs are small plot variety trials evaluating 50+ varieties in seven locations, which gives us a better idea of the genetic potential of a lot of varieties. Results for the OVTs can be found at swvt.uga.edu.

We are looking forward to seeing everyone at winter production meetings. Your county agent should have distributed meeting dates, and they can also be found at ugacotton.com. As always, if you ever need anything don’t hesitate to reach out. Your local UGA county Extension agents and specialists are here to help! camphand@uga.edu

NORTH CAROLINA | Guy Collins

Naturally, variety selection will be on growers’ minds during the winter months.  Variety performance will be covered in depth during our winter county meetings in February. County meeting dates, times and locations can be found in the NCSU Cotton Portal, under “Events,” or directly at https://cotton.ces.ncsu.edu/events/.

In the meantime, growers can observe variety performance data for both the North Carolina On-Farm Cotton Variety Evaluation Program and NCSU Official Variety Trials (OVT) through the NCSU Cotton Variety Performance Calculator, which can be found on the NCSU Cotton Portal, under “Calculators and Decision Aids,” or directly at https://trials.ces.ncsu.edu/cotton/select_trials/. This calculator allows users to customize how they want to observe variety performance data, over years, locations, etc. 

Last year’s experiences are the freshest on growers’ minds, and rightfully so. Likewise, the conditions our crop experienced certainly influenced variety performance and should be considered. However, observing multi-year data is very important when determining which varieties are the most consistent performers year-in, year-out. Growers tend to observe variety performance data from trials located near their farm, under the assumption that the general climate and soils are most similar to their own farm. This is understandable; however, over the past several years, we have frequently observed that variety data statewide and from dissimilar regions, soils or climates is actually more applicable to growers versus observing only local data when it comes to determining the best performing varieties.

Given that few of our acres are irrigated, yields are often wildly variable from year to year, strongly dependent on environmental conditions within a particular year (rainfall during the summer months, fall weather) and unpredictable. The best way to determine the most consistent performers across wildly variable environments is to observe variety performance in as many replicated trials as possible, even from dissimilar soils or rainfall amounts, or from distant areas of the state.

There was a lot of chatter last year about ThryvOn technology, given that we experienced enormous thrips pressure in the spring, cool weather resulting in abnormally slow growth and now, acephate-resistance in places. I think the data is clear from my entomology counterparts that ThryvOn is effective technology in this regard and certainly should be considered moving forward. Due to regulatory hurdles, 2023 was the first year that ThryvOn could be entered into OVT, so we will know soon how these varieties perform against our other top-performing varieties over the last couple of years.

Regardless, when considering which varieties to plant, growers should remember thrips pressure varies from year to year, and it has been quite a while since we’ve experienced the pressure that occurred in the spring of 2023. Thrips resistance to acephate is new to us, but there will likely be some more affordable foliar options in 2024. Additionally, the extra cost of technology should be weighed against performance and consistency of these new varieties. guy_collins@ncsu.edu

TENNESSEE | Tyson Raper

The 2024 season will likely see another massive shift in varieties planted; chances are, better than half of our acreage will be planted to new varieties. Our seed companies generally do a very good job advancing lines that do not flop, but I would encourage you to be careful moving too many acres into varieties with very little supporting data. Instead, try to keep a good, even mix between brand new varieties, varieties that have shown potential and the tried-and-true varieties; that strategy will be the best way to minimize risk.

When selecting brand new varieties, it is often helpful to broaden the window of testing data you evaluate to include adjacent states, or even regions. Our weather patterns are fairly consistent across multi-county production regions within a given year, so we typically recommend looking at multi-year data to select varieties best suited to your area. With brand new varieties, multi-year data is often not available. Looking through data in adjacent states or regions can serve as a proxy for multi-year data to help you understand how those brand-new varieties will perform if weather conditions vary. traper@utk.edu