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February 10, 2020 - Interpretation of the 2019 UGA Variety Trials from the eyes of your East GA PhytoGen CDS

In this month's blog I breakdown the 2019 UGA Variety Trial results more visually to demonstrate variety fit

As wintery weather traveled through many parts of North Georgia during the first parts of February, it has still remained relatively warm in South Georgia. Many images of white flies still lingering and extremely infested roots by root-knot nematodes are not uncommonly shared. If a very late cold front doesn't clean up, a variety such as PhytoGen® brand PHY 500 W3FE may really work in 2020, simply from its smooth leaf and root-knot nemadode protection package. We will have to wait and see what Mother Nature lends us for the start of #Plant2020. 

For those of you who have been reading along as I have tried to establish my "blog prescence," you may have noticed I have never really gotten very personal in any of my articles. You may have been wondering if these were simply robotically generated. This month I wanted to do something more personal and invite you a little further into my world. I hope to share many stories with you as I continue to 'Thrive with PhytoGen,' but this month I will share some background before I came to the team. 

There's a lot leading up to how I ended up working at a university research farm in Jackson, Tennessee, prior to joining the PhytoGen team, but that's for another time. While most student workers come to the farm to pick up a hoe for the summers as 18- to 20-year-old kids, I started looking for a full-time opportunity as a 22 year old. I gave that job my all, trying to find ways to stand out.

Working for an Extension cotton specialist, I was always so excited to finally enter the last test weight and see the final summary. By watching my mentor I quickly learned there is more to just looking at that list of averages, seeing who placed where. Being a visual learner interested in mapping AND an agronomist, I started making "heat maps," color-coding the data, to give a consistency to a visual. 

But what if we can do more? What if we could take the data we have and smooth it across similar environments to get greater visual ideas of variety fit? We know that the top 3 or 4 in the trial are the performers of major consideration, and if we map it out, it lets us see very quickly if a variety performs well across the board. We can tell if it rises to the top because it was really strong in certain areas while weaker in others. I told you I'd get somewhere with this, welcome to this month's blog.

First, I mapped out all counties in Georgia with more than 1000 acres reported. I then joined all the 2019 UGA On-Farm Variety Trial and OVT data to its respective county. From here, I built a macro that would average my data parameter of interest across neighboring counties. This allows locations that did not have trials to utilize neighboring county data and make a prediction on what the averages may have looked like. It also helps to more precisely estimate yield potential amongst neighboring counties with trials. From here I am able to generate a statewide average and maximum yield prediction map. While accuracy from counties with fewer neighbors or trials in the area decreases, there is still a lot we could do with this map, such as overlay annual rainfall, majority soil type, humidity, average temperature, etc. 




But we need to make a decision on a variety, and feel confident in that selection. We want to find something that has consistently high yield and fits a wide variety of environments, such that whatever situation Mother Nature places us in, we have an opportunity to perform well. From the stand point of first auxin tolerant varieties, there is no question DP 1646 has been the leader. This is firmly supported by its strong grasp on the market across the Cotton Belt. While it continues to excel, there is a new kid on the block in PhytoGen brand PHY 400 W3FE. 

Over the past few years in my university position I recommended a lot of the top competitor variety and have toyed with it just about every way imaginable to maximize yield and return. Even so, I was still extremely excited to join the PhytoGen team, 1) from respect of their people, 2) the potential of the breeding traits platform, but 3) because of the difference I was seeing in the experimental lines I was repeatedly traveling over in an open cab plot sprayer. Now I am not making claim to have seen a lot of historical varieties in my short time, but I don't think I have ever seen a plant like PHY 400 W3FE. After a year in on-farm testing, the difference is showing. It has won the majority of the states along the Mississippi Delta and goes blow-for-blow with DP 1646 just about everywhere else. 

Below you will see the yield fit results I plotted for the two included PhytoGen varieties, as well as DP 1646, and the next highest market share leader, NG 5711. Here is how I calculate my definition of "yield fit." First, I find the maximum yield from each individual trial, as this should be in the realm of the best yield possible for that environment. I then find what percentage each variety is within that trial of the maximum yield weighed. I define this as my measure of "yield potential." This normalizes a variety's potential across different growing conditions by looking at a percentage instead of a weight difference. I then want to see how strong a variety was in that area, was it a tight race amongst all, or just at the top. I define this as my "horsepower" measure, calculated by finding the percent of trial average, or variety yield divided by trial average yield. I then calculate my yield-fit index by averaging my yield potential and horsepower measures. The higher yield fit (darker green), the more times it was at the top of a county trial or was much stronger than the trial average. In other words, the better fit it would be for that area. The lower the yield fit (darker red), it's likely there is a better option for that area. 



So what do I see when looking at the 2019 UGA On-Farm Variety results? First, I see that no one variety is the perfect match for every county. I see a lot of opportunity for an early-mid maturing product to perform well in trials north of I-16. Across the board I see PHY 500 W3FE holding consistent to ST 5471 and DP 1840 on overall fit, with its strength in high yield environments. But the biggest difference are in DP 1646 and PHY 400 W3FE. Not only greater varietal fits, but near perfect consistency across south Georgia. 

While I cannot deny the competitor's abilities, it's 2020 -- the new decade, the world of 3-gene bollworm-protection. PhytoGen has a product that provides what we are looking for in consisently high yield potential in a wide range of environments with this technology. There certainly is reason to try PHY 400 W3FE in 2020. If RKN and bacterial blight resistance with Widestrike 3 isn't enough, let the yield stability be the reason. 

If you have further interest in this type of mapping or particular images, don't hesitate to reach out. I will also be discussing in a little more detail at upcoming grower meetings. A few of these you will find in the announcement below. Hope to see you there!

For more information about cotton production practices in your area, contact your state Extension cotton specialist. As always, your PhytoGen cotton development specialist also is available to discuss agronomic options.

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COTTON DEVELOPMENT SPECIALIST:

SHAWN BUTLER, PH.D.

Shawn Butler is the PhytoGen cotton development specialist for central and eastern Georgia. A native of Jackson, Tennessee, Shawn holds a doctorate in agronomy and crop science and a master’s degree in crop pathology, both from the University of Tennessee, specializing in application technology, precision agriculture and remote sensing. He enjoys helping cotton producers find applied solutions and implementing technology to overcome agronomic challenges. When Shawn isn’t scouting fields and visiting with growers, he enjoys following sports, playing golf, boating, and projects around the yard and home.
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