Variability of Cotton Yield and Quality

Abstract

Precision agriculture technologies offer an opportunity to vary production inputs within a field. Variable rate application offers the potential to increase production efficiency and minimize potential adverse environmental effects of agricultural chemicals. As an initial step in the development of precision agriculture technologies for cotton, studies are needed to document variability of cotton. The primary objective of this study was to document variability of yield and quality of irrigated cotton within and across three growing seasons. This study was conducted on a 5.3 ha irrigated field located at the Erskine Research Farm at Texas Tech University, Lubbock, TX. The crop was grown under a conventional tillage system with a 1.0 m row spacing. With the exception of sample collection, the field was managed traditionally with respect to production inputs. A grid system (57 points) was established on 30.5 m (approximately 0.1 ha) intervals. Production of fruiting 351 ORDER REPRINTS sites, fruit retention, lint yield, fiber length, strength, micronaire, and gross revenue were estimated for each grid point. Soil chemical and physical properties were also determined for each grid point. Highest variability was observed for lint yield and production of fruiting sites, and lowest variability was observed for lint quality parameters. Yield was correlated to production of fruiting sites each season. Nitrate concentrations were highly variable, and yield was negatively correlated to nitrogen (N) in 1997. This suggests that variable application of N may be a viable management option in the future. Yield was positively correlated to calcium (Ca), pH, and CEC in 1997. Yield variability was correlated across growing seasons. Gross revenues were quite variable, due primarily to yield variability.

Variability in Yield and Fiber Technological Properties of Cotton (Gossypium hirsutum L.)

“…In the study, 9 cotton breeding lines had higher values than the control variety 'GW-Teks' for this trait. Similar results were reported by Elms et al (2001) who observed average fiber length between 24-30 mm and the CVs for fiber length ranged from 2.3 to 4.2% in their studies. Fiber length is primarily determined by the variety, but is also influenced by temperature, water, nutrient stresses, and planting date (Elms et al, 2001;Davidonis et al, 2004).…”

“…Similar results were reported by Elms et al (2001) who observed average fiber length between 24-30 mm and the CVs for fiber length ranged from 2.3 to 4.2% in their studies. Fiber length is primarily determined by the variety, but is also influenced by temperature, water, nutrient stresses, and planting date (Elms et al, 2001;Davidonis et al, 2004). Contradictory results can result from the cultivars having different genetic backgrounds and from changes in environmental conditions.…”

“…Asif et al (2008) revealed higher coefficient of variability for fiber fineness and suggested that this character is highly influenced by non-genetic biotic and abiotic factors. Elms et al (2001) observed an average fiber micronaire between 4.5-5.1 and they reported that lower micronaire values were associated with immature fibers.…”

Effects of Deficit Drip Irrigation Ratios on Cotton (Gossypium hirsutum L.) Yield and Fibre Quality

“…These bolls tend to be less mature at harvest, and, therefore, have a lower value for micronaire under irrigation conditions (Davidonis et al. 1996, Elms et al. 2001, Pettigrew 2004).…”

Managing Spatial and Temporal Variability in Irrigated Agriculture Through Adaptive Control

“…For example, there is typically a ten fold wine grape yield variation across vineyards in any given year (Bramley & Hamilton, 2004). Spatial and temporal variability has also been reported in cotton (Elms et al, 2001;Meredith, 1996;and Wilkerson & Hart, 1996), corn (Chen et al, 2000;Krachenko et al, 2005;and Saddler et al, 2002), wheat (Ciha, 1984;Jin & Jiang, 2002;and Kelly et al, 2004), and vegetables (Barber & Raine, 2002).…”