Understanding Cotton Product Ratings

Deltapine® branded cotton products use a general product rating scale that ranges from 1-9, where 1 is excellent and 9 is poor. Other characteristics like fiber quality ratings or seed size are based on quantitative data. Product ratings are relative and can be used to make comparisons between Deltapine® branded products only, as comparisons to competitor products may be inaccurate since ratings between companies may not be the same.

Plant Characteristic Ratings

Plant characteristic ratings, including adaptation and agronomic characteristics, are based on internal testing during product advancement, as well as knowledge of the background of related products used during breeding. These ratings provide essential information to growers for on-farm positioning.

Maturity. A relative measure of the time it takes from planting for the cotton product to reach maturity. The second two numbers in the Deltapine upland variety cotton naming system indicate maturity based on the following scale: early (10-19), early-mid (20-29), mid (30-39), mid-full (40-49), and full (50-59). This is an estimate and actual maturity can vary based on environmental conditions and geographic location. Deltapine pima cotton varieties have relative maturity descriptions, but do not use the numbering system described for Deltapine® upland varieties.

Plant height. Rated as short (S), medium-short (MS), medium-medium short (MMS), medium (M), medium-tall (MT), medium tall-tall (MTT) and tall (T). This can vary with environmental conditions.

Leaf type. Rated as hairy (H), light hairy (LH), semi smooth (SS), and smooth (S). Leaf type can help reduce pest pressure and increase harvest efficiency.

Seed size. A measure of the number of cotton seeds per pound.

Storm resistance. Helps to describe how tight or loose the cotton fibers are in the boll. Rated on a scale of 1-9, with 1 having a tight, stripper-like boll, and 9 having a loose boll.

Fiber Quality Ratings

Fiber quality ratings are based on internal testing during product development and include high volume instrument (HVI) testing to determine average fiber quality values for each cotton product.

Lint percentage (%). This is the average percentage of lint taken from the total weight of seed cotton.

Staple (32nds). This is the average length of the cotton fibers and is measured in 32nds of an inch. To help maximize fiber length, proper management and ideal growing conditions are necessary during fiber elongation.

Micronaire. This is measured by the resistance of airflow through a 2.34 grams fiber sample that is compressed to a specific volume. This is an indication of average cotton fineness and maturity. Environmental conditions can be a strong factor in determining micronaire.

Strength (g/tex). Strength is measured as grams per tex, which is the force required to break a bundle of fibers one tex unit in size. A tex unit is equal to the weight in grams of 1000 meters of fiber. This value is an indication of the average strength of the cotton fibers: 31 or higher (very strong), 29-30 (strong), 26-28 (average), 24-25 (intermediate), 23 and below (weak).¹

Length uniformity (%). This measures the evenness and strength of the cotton fibers as a percentage. It is the ratio between the average length and the average length of the longest 50% of the fibers. The uniformity index indicates values above 85 as very high, 83-85 (high), 80-82 (intermediate), 77-79 (low), and below 77 (very low).

Disease Ratings

Disease ratings are more difficult to generate because it can be difficult to simulate disease presence with consistent severity across multiple locations for comparable evaluations. Plant breeders artificially inoculate products with disease pathogens for evaluation. However, if conditions are not favorable for disease development each year, the incidence of disease may not be adequate for evaluation. Therefore, ratings for specific diseases are not always available for all products. Each disease listed has a slightly different disease rating scale.

The product’s level of tolerance to diseases of concern is rated, when possible, either on a 1-9 scale with 1 as excellent and 9 as poor, or based on susceptibility which includes susceptible (S), moderately susceptible (MS), moderately tolerant (MT), tolerant (T), partially resistant (PT), resistant (R). Ratings used are based on the disease of concern.

Plant description ratings

Nodes of first fruiting brance (NFFB). This value indicates the average number of nodes on the mainstem until the first fruiting branch develops.

Number of fruiting nodes. This is an average number of fruiting nodes per plant. This number can vary between growing environments and management.

Deltapine agronomists provide cotton product recommendations based on local conditions. To help find the variety for your field, use the Seed Finder to compare multiple products and include your selections in a Seed List for easy reference. Local seed guides can provide additional information for your area.

Sources

¹ Classification of upland cotton. Cotton Incorporated. https://www.cottoninc.com/cotton-production/quality/classification-of-cotton/classification-of-upland-cotton/.
Web sources verified 06/10/22. 1410_31450