Have you recently found yourself thumbing through fiber quality data wondering, ‘how do they generate this data, and what does it all mean, again?’  In the last 2021 Cotton Focus Video Series entry, I give a brief walk-through of the University of Tennessee MicroGin and highlight a publication from last year by Steve Brown and Tyler Sandlin (Auburn University) covering explaining the process of fiber development and fiber quality.  I also highlight results from a recent MidSouth Cotton Specialists’ effort which re-evaluated the role of variety selection, the environment and management on realized fiber quality.   

Over the years, I’ve noticed a large range in the level of understanding of fiber development, the classification process, and what role our decisions make on realized fiber quality.  While some within the industry can determine leaf, staple and color from the turn-row in a split second, others may not understand why their cotton ‘high-miked’.   There have been several publications over the years that I’ve found to be particularly efficient and effective in explaining fiber quality.  The Classification of Cotton, developed by Cotton Incorporated, is one of those publications; the publication does an excellent job of describing the history and process of classification and touches on the role of environment and variety on each parameter.  The old Physiology Today Series, as you might expect, tackled the subject several times.  Another excellent document that I highly recommend reviewing was published last year: How to Think about Fiber Quality,  by Steve Brown and Tyler Sandlin, does an excellent job of explaining fiber development from the production side- specifically how our decisions of management or variety selection might impact fiber quality parameters.

For those that have been in the industry for many years, you’ve probably noted substantial shifts in Midsouth fiber quality.  During the 2015 and 2016 seasons, The Midsouth Cotton Specialists’ Working Group compiled data across all large strip trials and analyzed the data to determine the role of environment and cultivar on realized fiber quality.  This exercise has been completed several times within several different regions, but it had been quite some time since an analysis had been completed within the Midsouth.  You can access our complete refereed journal article here, but let me summarize the most important points- I believe they will help you understand why every variety selection discussion I have with a grower tends to move quickly towards fiber quality.

First, as you might expect, the environment drove yield; if the weather is terrible, it doesn’t matter which variety we planted- yield suffered.  On the flip-side, if the environment was favorable, yields were good- and the role of cultivar only resulted in a small swing in lint yields.  A caveat here- keep in mind the analysis included widely planted, adaptable, high-yielding varieties- the role of variety in determining yield would have been greater if we had included varieties that consistently fall outside of the top-performing statistical group.  Basically, if you are selecting varieties out of the top-statistical group, yield differences within that group are often small.

In contrast, realized micronaire and fiber length were evenly split between environment and variety; regardless of environment, a large portion of micronaire and fiber length was determined by the variety we planted; specifically, variety determined 42.6% of micronaire and 49.6% of length.  Most other fiber quality parameters are largely driven by environment, with the exception of strength- almost 20% of realized strength was determined by the variety planted.

To quote our conclusions, ‘The relatively minor role of cultivar in determining lint yield and the substantial role of cultivar in determining micronaire and length suggest that producers within the Mid-South should begin to place more value on fiber quality data when selecting among high-yielding cultivars.‘

Again, thanks for joining us for the 2021 Cotton Focus Video Series.  We will have  a quiz next week for those interested in receiving points. Best of luck in the coming weeks, and look forward to seeing you in the field.