Genotype × environment interaction and multi-trait stability of cotton lint yield and fiber quality across irrigated and rainfed environments

Cotton fiber quality and textile yarn quality can be affected by ginning processes and cotton cultivars. The overall goals of this study were to utilize a microgin to evaluate the effect of seed cotton cleaner and lint cleaner on fiber and yarn quality, and to benchmark FiberMax 1740 and Phyto Gen 370 against Deltapine 555 grown in Georgia. Six cleaning treatments in a microgin were arranged by varying seed cotton cleaners (stick machine, cylinder cleaner, and Trashmaster) and one saw-type lint cleaner. Cotton fiber quality and cotton trash content were measured via High Volume Instrument (HVI), Advanced Fiber Information System (AFIS), and Shirley trash analyzer. Ring yarn quality was measured in terms of spinning efficiency, tensile strength and elongation, hairiness, defects, and waste. Fiber quality measured by HVI showed significant differences between the six cleaning treatments in both trash content and fiber length properties. Specifically, the saw-type lint cleaner was more effective in reducing trash content but was more likely to create short fiber content than the seed cotton cleaner. Deltapine 555 demonstrated lower upper half mean length and lower length uniformity than FiberMax 1740. A similar pattern was observed in AFIS data, although cleaning treatments only showed impact on total trash count, visible foreign matter, and neps. The three cotton cultivars exhibited significant differences in cotton length properties. Deltapine 555 had the highest short fiber content (by weight) and lowest length uniformity among the three cultivars. Results from Shirley analyzer revealed that the cleaning treatments without the saw-type lint cleaner had both higher visible and invisible trash content. As for the ring yarn quality, cotton lint with less cleaning processes exhibited lower defects, lower hairiness (irregular CV), but more waste than that with more cleaning processes. Given the waste can be cleaned during the carding process and easily manageable, the less ginning options could be beneficial to spinning process. Among the three cultivars, Phyto Gen 370 generated the highest quality yarn suggesting that Deltapine 555 can be replaced by other cultivars with improved yarn quality. This study sheds light on the effect of cleaning and cotton cultivar on lint fiber quality and the spinning performance of the fiber. The information could be useful to improve the profitability for cotton growers, ginners, and spinners alike.

Cotton fiber quality is important to the producer because reduced quality results in a significant monetary penalty. Therefore, to maximize profitability, the producer must also attempt to control the quality of the crop while maximizing yield. The tools of precision agriculture appear to be well suited to this task. The objective of this research was to measure the natural variability present in cotton fiber yield and quality parameters. Cotton, variety LA 887, was grown in a producer's field in Florence SC for two consecutive years. Soil (0–20 cm) and fiber samples (1 m row) were collected from a regular grid (120 * 40 m, 7.5-m interval). Soil properties determined included soil moisture, soil texture, organic matter, pH, Ca, Mg, K, P, and Na. Fiber quality was estimated by several methods, including the high volume instrumentation (HVI) method and the advanced fiber information system (AFIS). The HVI method is used by USDA-AMS to class and price cotton and the AFIS system is used primarily by cotton researchers. All fiber and soils data were analyzed by both conventional statistics (univariate and correlation) and geostatistical techniques (variogram analysis and kriging). Soils data was found to be non-normally distributed and spatially correlated. Fiber yield was normally distributed and spatially correlated and fiber quality varied in both its distribution and spatial correlation. Soil pH, soil phosphorus and soil organic matter were correlated with fiber yield and a number of fiber properties, including micronafis, immature fiber fraction (IFF), fine fiber fraction (FFF), cross-sectional area (An) and micronaire. Kriged maps of soil properties provided useful indicators of fiber yield and quality variation.

Cotton (Gossypium hirsutum L., variety latifolium Hutch) is produced by more than 60 countries and, despite the quality and multiplicity of its seeds use it is grown mainly for the production of fibers. The quality of the fiber can differ between different production environments, being a key factor in determining the price and quality of cotton destined for textile products. These differences in quality are mainly associated with cultivars and meteorological conditions, which influence the indicative parameters of fiber quality. The knowledge of the factors that condition the quality of the cotton fiber is important for the definition of the regions with potential for the production of superior quality fibers. Thus, as a way to subsidize the production of better quality cotton fibers, this work aimed to identify and classify the factors that interfere with the quality of the cotton fiber. Data from meteorological variables and cotton fiber quality indices of 32 Brazilian cultivars were submitted to Pearson's correlation and cluster analyses. These analyses were performed considering three phases of the cotton cycle: total cycle; last 100 days of the cycle; and last 50 days of the cycle. Finally, the results of correlation and clustering analysis were compared. In general, considering the total cotton cycle, it was possible to obtain better statistical correlations between the meteorological variables and the quality of the cotton fiber.

Nitrogen fertilizer sources and tillage effects on cotton growth, yield, and fiber quality in a coastal plain soil

Estimating cotton fiber quality early in the season, or its field variability, is impractical due to limitations in current methods, and it has not been widely explored. Similarly, few studies have tried estimating the parameters contributing to in-season cotton yield using UAV-based sensors. Thus, this study aims to explore the potential of using UAV-based multispectral images to estimate important in-season parameters, such as intercepted photosynthetically active radiation (IPAR), cotton height, the number of mainstem nodes, leaf area index (LAI), and end-of-the-season yield and cotton fiber quality parameters. Research trials were carried out in 2018 and 2020 in two experimental fields. In both years, a randomized complete block design was used with three cotton cultivars (2018), three plant growth regulators (2020), and three different irrigation levels to promote variability (both years). Cotton growth parameters were collected throughout the season on the same dates as UAV flights. Yield and fiber quality data were collected during harvest. The VI-based models used in this study were mostly sensitive to differences in cotton growth and final yield but less sensitive in detecting variation in cotton fiber quality indicators, such as length, strength, and micronaire, early in the season. The best performing regression model among the three fiber quality indicators was achieved in 2020, using a combination of four VIs, which explained 68% of the micronaire variability at 71 DAP. Results from this study also showed that multispectral-based VIs can be applied as early as the squaring stage at around 44 DAP to estimate most cotton growth indicators and final lint yield. Multiple linear regression validation models for height using NDVI, GNDVI, and RDVI obtained an R2 of 0.62, and for LAI using MSR and NDVI an R2 of 0.60. For lint yield, the best regression model combined four VIs and explained 66% of the yield variability. The ability to capture the variability in important growth and yield parameters early in the season can provide useful insights on potential crop performance and aid in in-season decisions.

Cotton (Gossypium hirsutum L.) is the world’s leading fiber crop, grown or processed in many countries, providing a major contribution to their economies. Yield is economically most important to a producer which drives cultivar development and adoption; however, fiber quality is the primary focus for spinning mills. Cotton fiber quality must improve to remain competitive with synthetics due to increased demands for lightweight casual garments which require longer, stronger, and finer fibers. Improved cotton yields and fiber quality have continued to be realized through science-based plant breeding, particularly in countries and production systems with suitable climate and appropriate management inputs to maximize those improvements. The most significant challenge for cotton breeders has been to combine high yield with improved fiber quality, due to negative associations between yield and quality attributes in G. hirsutum. This chapter highlights practices to enable simultaneous improvement of yield and fiber quality during conventional breeding. There are adequate genetic resources available for innovative cotton breeders to make more progress, but new tools being offered by modern molecular technologies will achieve those gains more efficiently. Advances in fiber quality science have been made in cotton biotechnology – by improving our understanding of fiber development phases that contribute to fiber quality through gene discovery, genome mapping, and identification of linked molecular markers. Novel biotechnology traits have the potential to improve fiber yield and quality by altering the developmental phase associated with fibers per seed, fiber length, strength, and fineness. Biotechnology tools to facilitate improved conventional breeding through marker-assisted selection are also under development, particularly high-throughput techniques based on single nucleotide polymorphisms derived from next-generation sequencing. There are clearly great opportunities for better integration of conventional breeding and molecular biology, and as new GM traits are developed, a future challenge will be to combine multiple GM traits into elite cultivars. This could be assisted by the judicious use of molecular markers to herald a new age in cotton improvement. Cotton is one of the pioneer crops for the introduction of genetically modified (GM) insect and herbicide resistance, with about 80 % of global cotton being GM by 2012. That experience of research and deployment of these first-generation GM traits provides the foundation for development and exploitation of GM novel fiber property traits in the future.

In general, the quality of fruits depends on local conditions experienced by the fruit during its development. In cotton, fruit quality, and more specifically the quality of the fibre in the fruit, depends on interactions between fruit position in the plant architecture, temperature and agronomic practices, such as sowing time, mulching with plastic film and topping of the plant's main stem and branches. To quantify this response of cotton fibre quality to environment and management, we developed a simulation model of cotton growth and development, CottonXL. Simulation of cotton fibre quality (strength, length and micronaire) was implemented at the level of each individual fruit, in relation to thermal time (represented by physiological age of the fruit) and prevailing temperature during development of each fruit. Field experiments were conducted in China in 2007 to determine model parameters, and independent data on cotton fibre quality in three cotton producing regions in China were used for model validation. Simulated values for fibre quality closely corresponded to experimental data. Scenario studies simulating a range of management practices predicted that delaying topping times can significantly decrease fibre quality, while sowing date and film mulching had no significant effect. We conclude that CottonXL may be used to explore options for optimizing cotton fibre quality by matching cotton management to the environment, taking into account responses at the level of individual fruits. The model may be used at plant, crop and regional levels to address climate and land-use change scenarios.

Excessive weathering may diminish cotton (Gossypium hirsutum L.) lint yield and fiber quality to the extent that economic losses occur for the producer. Our objective was to determine the effects of systematic delayed harvest on cotton lint yield, fiber quality, and profitability. Experiments were conducted from 1998 to 2000 at the Coastal Plain Experiment Station, Tifton, GA, on a Tifton loamy sand (fine‐loamy, kaolinitic, thermic Plinthic Kandiudults). The treatments consisted of a standard harvest‐aid combination applied at weekly intervals over a 13‐wk period beginning at first open boll. Harvest aids were applied to each plot according to its week after first open boll designation and machine harvested 2 wk thereafter. After ginning, fiber quality was determined on lint samples from each plot. High volume instrument (HVI) fiber length uniformity was greatest in 1999 and 2000 when harvest aids were applied between 58 and 88% open boll, while the advanced fiber information system (AFIS) fiber length by number coefficient of variation and short fiber content by number were lowest when harvest aids were applied from 40.1 to 46.8% open boll. The HVI upper half mean fiber length and the AFIS mean fiber length by number were greatest when harvest aids were applied between 39.1 and 56.7% open boll. In 1999 and 2000 lint yield and adjusted gross income were greatest when harvest aids were applied from 76.5 to 89.0% open boll. Results from this study indicate optimum fiber quality is established earlier during boll opening than lint yield and profitability.

Fiber yield and quality in cotton under drought: Effects and management

Cotton irrigation in the Texas High Plains (THP) is often dictated by the well capacity and not by the water needs of the crop. The source of irrigation-water is the Ogallala aquifer and in many areas of the THP, the water table has declined to well capacities that deliver 1.3 to >7.6 mm/d. There is plenty of information on cotton responses to irrigation frequency and amount; however, information on when to terminate irrigation and its effect on cotton lint yield and fiber quality is scarce. Our objective was to evaluate over a 4-year period three irrigation termination thermal times corresponding to cumulative daily heat units (∑HU) of 890 °C, 1000 °C and 1110 °C from crop emergence, and three levels of irrigation (2.5, 5.1 and 7.6 mm/d) on cotton lint yield and fiber quality. Irrigation was applied with a sprinkler system on a 3-day frequency in Lubbock, TX. Results showed that on average the 7.6 mm/d level produced the most cotton lint yield regardless of the irrigation termination thermal time. Terminating cotton at 1000- °C ∑HU resulted in water savings of 25 to 50 mm for the 2.5 and 5.1 mm/d levels without significantly affecting lint yield. For the 7.6 mm/d and terminating at 890- °C ∑HU resulted in water savings of 100 to 115 mm. Average fiber length statistically increased with termination thermal time and level. This effect was most significant in years with the least rain and warmer air temperature. Micronaire increased with the termination thermal time in years with >500 mm of rain. Average fiber length uniformity and fiber strength were minimally affected by termination thermal time. As irrigation level increased, the average micronaire decreased, and fiber strength increased for the 5.1 and 7.6 mm/d irrigation. We concluded that in the THP for well capacities that deliver 2.5 - 5.1 mm/d irrigation can be terminated when the ∑HU reaches about 1000 °C from emergence without impacting cotton lint yield.

Potassium (K) deficiency is a common yield‐limiting factor in cotton ( Gossypium hirsutum L.) production, requiring effective management to minimize yield losses and maintain fiber quality. We evaluated how K availability influences cotton lint yield and fiber quality. Ten fertilizer‐K rate (0–187 kg K ha −1 ) trials were conducted on silt loam soils with soil‐test K (STK) ranging from very low to above optimum during the 2023 and 2024 growing seasons. Cotton was planted in raised beds and furrow‐irrigated, and lint yield, turnout, and fiber quality (i.e., fiber length, micronaire, uniformity, strength, and elongation) were measured at maturity. Cotton lint yield was positively affected by fertilizer‐K rates ( p ≤ 0.10) at STK ≤ 114 mg K kg −1 . Yields were maximized at responsive sites with applications of 56 kg K ha −1 in long‐term trials and 37, 75, or 112 kg K ha −1 in single‐site‐year trials, showing yield increases of 20%, 53%, 47%, and 70% compared to the no‐K control, respectively. Lint turnout and fiber quality were affected by K availability. Overall, at yield‐maximizing fertilizer‐K rates, lint turnout was 2.4% greater across cultivars in relation to the control. Similarly, fiber elongation increased by 0.35%. At sites with Very Low STK, as little as 37 kg K ha −1 increased lint uniformity and strength up to 0.67% and 1.84 g tex −1 . Micronaire increased on average by 0.50, with greatest values occurring with 112 kg K ha −1 application. These findings suggest adequate K management is key to maximizing both cotton yield potential and fiber quality.

Effects of planting dates and shading on carbohydrate content, yield, and fiber quality in cotton with respect to fruiting positions

Yield-enhancing compounds are among the many inputs used in cotton (Gossypium hirsutum L.) production systems across the United States Cotton Belt. Some of these products, however, have not been adequately tested in field settings and their impact on cotton yield and quality is unknown. Messenger, marketed by the Eden Bioscience Corporation (Bothell, WA), is a new product containing a protein that may stimulate the hypersensitive response of higher plants, resulting in increased yields. The objective of our investigation was to determine if Messenger applications would result in enhanced cotton crop maturity, lint yield or fiber quality. Messenger studies were conducted in Colquitt, Grady, and Tift Counties in South Georgia and at the University of Georgia Coastal Plain Experiment Station (UGA-CPES) in Tifton in 2000. Plot size at each location ranged from 1.2 ha (Grady County) to 0.01 ha (UGA-CPES). Messenger was applied as a foliar treatment at several stages of crop development at each location with either a John Deere (Moline, IL) high clearance sprayer or a CO2 backpack sprayer. Mid- and late-season plant maps at each location revealed no significant differences in crop maturity among the treatments. Lint yields in Colquitt, Grady, and Tift Counties and the UGA-CPES averaged 1159, 941, 1292, and 1654 kg ha− 1, respectively with no significant treatment differences within a location. Likewise, Messenger did not significantly affect fiber properties at any location. *Mention of a trademark, proprietary product, or vendor does not constitute a guarantee or warranty of the product by the University of Georgia, the U.S. Department of Agriculture, or other cooperating agencies and does not imply its approval to the exclusion of other products or vendors that may also be suitable. Messenger, Eden, and Eden Bioscience are registered trademarks of the Eden Bioscience Corporation.

Optimal row spacing configuration to improve cotton yield or quality is regulated by plant density and irrigation rate

We previously reported on the strong symbiosis of AMF species (Rhizophagus irregularis CD1) with the cotton (Gossypium hirsutum L.) which is grown worldwide. In current study, it was thus investigated in farmland to determine the biological control effect of AMF on phosphorus acquisition and related gene expression regulation, plant growth and development, and a series of agronomic traits associated with yield and fiber quality in cotton. When AMF and cotton were symbiotic, the expression of the specific phosphate transporter family genes and P concentration in the cotton biomass were significantly enhanced. The photosynthesis, growth, boll number per plant and the maturity of the fiber were increased through the symbiosis between cotton and AMF. Statistical analysis showed a highly significant increase in yield for inoculated plots compared with that from the non inoculated controls, with an increase percentage of 28.54%. These findings clearly demonstrate here the benefits of AMF-based inoculation on phosphorus acquisition, growth, seed cotton yield and fiber quality in cotton. Further improvement of these beneficial inoculants on crops will help increase farmers’ income all over the world both now and in the future.