Relationship of Seed Properties to Seed Coat Fragments for Mid-South Cotton Varieties

Abstract

Seed coat fragments (SCF) in cotton bales can cause processing problems for textile plants. . Previous research has shown that cotton cultivars differ considerably for the number and weight of SCF in lint. With the recent trend towards cultivars with smaller seed, there has been some concern that increased SCF levels could result from smaller seed that are more easily damaged or more likely to pass through ginning ribs. Therefore, the objective of this study was to analyze cultivar differences for SCF in lint and determine the relationship with other cultivar traits such as seed index, seed diameter, the distribution of seed diameter, or seed linter content. Sixty three cotton cultivars were planted in Stoneville, MS, in a randomized complete block design in 2004 as part of the Mississippi State Regional Cotton Variety Trial. The cotton was machine harvested and ginned with a typical sequence of gin machinery. Seed coat fragment content ranged from 9.4 to 29.1 SCF per gram of lint among cultivars. Seed index ranged from 7.1 to 10.7 grams per 100 seed, and mean seed diameter ranged from 4.5 to 5.2 mm. Cultivars differed significantly for seed diameter distribution. A polynomial relationship was found between SCF content and seed index with SCF initially increasing with seed index and leveling off or decreasing with larger seed index. A similar relationship was found between SCF content and seed diameter. No consistent relationship was found between SCF content and seed diameter distribution parameters. The results of this study showed no indication that cultivars with smaller seed, either overall or in the tails of the seed diameter distribution, were prone to higher SCF content.