Plant Density Modifications of Cotton Within‐Boll Yield Components

Abstract

One approach to improving cotton (Gossypium hirsutum L.) yield and quality is to identify crop management practices that may exploit the most basic (i.e., within-boll) yield components. One of the parameters that may influence within-boll yield components is plant density. Thus, the objectives of this investigation were to determine how yield components in cotton are altered through plant density management. Two cotton cultivars were overseeded and hand thinned to 3.6, 9.0, 12.6, and 21.5 plants m 22 in 2001 and 2002. Before machine harvest, plants from 6 m of one row were removed from each plot and hand harvested by fruiting position. After hand harvest, seed cotton from each fruiting position was ginned separately. Boll number, lint mass, seed number, seed mass, seed surface area, and fiber properties were determined for each fruiting position. These data were then used for yield component calculations. Lint mass boll 21 , individual seed mass, and seed number boll 21 decreased as plant density increased while total seed surface area m 22 of land area increased, which resulted in increased lint yield m 22 of land area. Lint mass cm 22 of seed surface area and fiber number seed 21 did not consistently respond to plant density. These results indicate that plant density management may influence total seed surface area per unit land area. Most within-boll yield components, however, appear to be controlled more by cultivar than crop management.Craig W. Bednarz, Texas Tech Univ. and the Texas Agricultural Experiment Station,

Effects of Irrigation, Cultivar, and Plant Density on Cotton Within‐Boll Fiber Quality

“…Similar results were found by Bednarz and Nichols (2005) at the fi eld level (i.e., when plots were machine harvested, blending seed cotton across fruiting positions, and ginned together), and by Bednarz et al (2006) at the canopy level.…”

“…Th e interaction occurred only in the year of abundant rainfall when the irrigation eff ects were probably diminished. Bednarz and Nichols (2005) observed fi ber maturity ratio reduction with increased plant density at the fi eld level (i.e., when plots were machine harvested, blending seed cotton across fruiting positions, and ginned together) and Bednarz et al (2006) showed a similar eff ect at the canopy level.…”

“…Bednarz and Nichols (2005) also showed that, at the fi eld level (i.e., when plots were machine harvested, blending seed cotton across fruiting positions, and ginned together), mean fi ber length and UQL did not diff er among plant densities. Additionally, Bednarz et al (2006) showed that, at the canopy level (i.e., when plots were hand harvested, segregating seed cotton across fruiting positions, and ginned separately), the lower plant densities resulted in longer mean fi ber lengths and greater UQL in only one of the studied environments.…”

“…Bednarz et al (2006) reported lower fi ber quality resulted from increased plant density. Rain distribution and irrigation strategies (Balkom et al, 2006;Lascano and Hicks, 1999), and cultivars (Bradow and Davidonis, 2000) could also aff ect cotton fi ber quality.…”

Leaf gas exchange, source–sink relationship, and growth response of cotton to the interactive effects of nitrogen rate and planting density

“…Better light interception, efficient leaf area development, and reduced weed competitiveness by early canopy closure are observed by (Wright et al 2011). Increase in planting density results in seed cotton yield by increasing number of bolls plant -1 and 100-boll weight; however, some reports contradicted that with an increase in plant density resulted in decreasing boll weight and number of bolls plant -1 (Sawan et al 1993;Bednarz et al 2006), but per hectare seed cotton yield increased due to more number of plants ha -1 (Dong et al 2006a, b). Relative water contents (RWC) explain turgidity of cells; however, reduction in turgidity results in reduced leaf water contents and declined water use efficiency (González and González-Vilar 2001).…”