Soil pH influence on cotton lint yield and quality

There have been conflicting results reported about the effect on cotton (Gossypium spp.) lint yield of altering planting and irrigation termination (IT) timing. The objectives of this study were to identify a planting window (PW), on a heat unit (HU) basis, and IT timing, as a function of crop growth stage, for optimum yield potential of Upland (G. hirsutum L.) and American Pima (G. babadense L.) cotton. Two PWs of Upland 'Deltapine 90' (DPL 90), Pima 'S-6', and IT treatments were included in field experiments for 11 site-years. Planting windows were defined as PW1 and PW2 for plantings prior to and following 600 HU accumulated after 1 January, respectively. Two IT treatments were imposed for each planting. Irrigation termination in the desert Southwest generally results in cessation of growth (crop termination). The first IT treatment (IT1), was imposed to ensure full development of bolls set up to cutout, and the second (IT2) was after two additional irrigations. From covariate analysis, there was no evidence of interaction between PW and IT, indicating that these treatments responded the same across the different environments for both cotton species. There were, however, differences in lint yields among treatments. For DPL 90, PW1 IT2 yielded 83 and 97 Ib/acre more than PW1 IT1 and PW2 IT2; and for Pima S-6, PW1 IT2 was 118 and 204 Ib/acre more than PW1 IT1 and PW2 IT2, respectively. Early planting is necessary for optimum yield potential of full-season cotton varieties; with the greatest yield coming from early planting and termination after the development of a second fruiting cycle (PW1 IT2). However, if a reduction in input costs and the avoidance of late-season insect pests are important considerations then cotton should be planted early (300 to 600 HU after 1 Jan) and terminated at the end of the first fruiting cycle (approximately 600 HU past cutout) to maintain the lint yield potential of full-season maturity types of Upland and Pima cotton.

Cotton acreage in the Coastal Plain of the Southeast has increased in recent years. The soils in this region are sandy and typically have a low retention capacity for sulfate S. A 3-yr (1993-1995) field test was conducted in south Alabama on a Lucy loamy sand (loamy, kaolinitic, thermic Arenic Kandiudults) to evaluate the response of cotton (Gossypium hirsutum L.) to the source, rate, and timing of S fertilizer applications. Sulfur was broadcast preplant as either ammonium sulfate, elemental S, potassium sulfate, potassium thiosulfate, or K-Mg-sulfate at rates of 0, 10, 20 and 40 lb S/acre. Additionally, ammonium sulfate was applied at first square to evaluate timing effects. Lint yields were increased each year and they peaked at a rate of approximately 20 lb S/acre on this Lucy Is soil. Averaged across sources, 20 lb S/acre increased lint yields by an average of 21% as compared with the no S check treatment. Lint yields were not affected by time of S application in 1993 or 1995, but a preplant application of S increased yield compared with S applied at first square in 1994. The response to time of S application was attributed to heavy rainfall that was received soon after the first square application of S. Sources of S did not affect lint yield in 1993 or 1995, but ammonium sulfate and K-Mg-sulfate produced slightly higher yields than those of other sources in 1994, an extremely wet growing season. Lint quality, as measured by high volume instrumentation (HVI), was not affected by any S treatment in 1993 or 1994. In 1995, fiber length increased with S rate, but the differences among sources were inconsistent. Results of this test suggest that cotton produced on sandy Coastal Plain soils that are low in S may require annual applications of 20 lb S/acre to ensure high yields. The S should be applied preplant, although delaying application to first square should not limit yields. For lint production, differences among commercial S fertilizer sources should be minimal.

The development of earlier maturing, cool temperature tolerant varieties of cotton (Gossypium hirsutum L.) has allowed cotton production to expand into regions with shorter, cooler growing seasons. The objective of this research was to evaluate the interactive effect of soil type, irrigation, and meteorological conditions on the water use and lint yield of cotton grown in four U.S. Great Plains soils. Cotton was grown in 2005 through 2007 in 48 weighing lysimeters which contained clay loam, silt loam, sandy loam, or fine sand at Bushland, TX, with irrigation beginning after emergence. The seasonal heat units (HU) from planting to harvest were 1010°C in 2005, 1075°C in 2006, and 985°C in 2007. From seedling to beginning boll development, reference evapotranspiration averaged 7.6 mm in 2005, 8.5 mm in 2006, and 6.7 mm in 2007. Lint yield was significantly related to open boll number at harvest in all soils and years. Averaged cotton lint yields for the 2005 and 2007 full and deficit irrigation treatments were significantly larger in the fine sand (160 g m−2) than in the other soils (126 g m−2). In 2006, cotton lint yield in the fine sand was significantly smaller (101 g m−2) than the average of the other soils (147 g m−2). Cotton lint yield increased in the silt loam soil and decreased in the fine sand as seasonal HU increased. Early season meteorological conditions which influenced square shedding and boll development may have affected lint yields interactively with soil texture and irrigation.

Cotton (Gossypium hirsutum L.) is an important crop in drought‐prone central Texas. Foliar potassium (K) application and skip‐row planting have the potential to improve productivity of rainfed cotton in this region. The objective of this study was to quantify the effects of skip‐row planting and foliar K on cotton lint yield, biomass, nutrient uptake, and lint quality in rainfed cotton from 2017 to 2020. Foliar K was applied at 0, 20, and 40 kg ha−1. Row arrangement treatments consisted of two planting geometries: 2 × 1 skip row and standard full row. Cotton yield was not affected by foliar K in all years or by row spacing in 2017, 2019, or 2020. In 2018 alone, there was greater lint yield from skip row (530 kg ha−1) compared to full row (423 kg ha−1). The skip‐row treatment resulted in significantly lower vegetative biomass and vegetative K uptake, but improved fiber quality. While foliar K application did not impact lint yield, total biomass and vegetative nitrogen and phosphorus uptake were increased with foliar K. There were year‐to‐year differences in seed and vegetative biomass, nutrient uptake, and lint quality, likely driven by differences in rainfall, with 2018 being unusually dry. Weather variation had more impact on cotton productivity than either treatment. However, given that the skip‐row treatment increased quality and yield in the driest year while not affecting yield in wetter years makes it a viable option for cotton producers looking to reduce costs and increase profits in drought‐prone regions.

Cotton lint yield variability in a heterogeneous soil at a landscape scale

Modern cotton (Gossypium hirsutum L.) cultivars with herbicide resistance have rejuvenated an interest in narrow row cotton production, primarily because of the reduction of weed control problems encountered in the past with narrow row systems. While the primary goal of narrow row cotton is to reduce production costs, an agronomic and physiological evaluation of this cropping system is also needed. The objectives of this study were to determine the feasibility of using modern cotton cultivars in narrow rows (30 cm) for cotton production in the Gonabad and to assess the effect of these various systems on cotton growth, lint yield, and fiber quality. Plant height, sympodia and total bolls per plant were reduced in cotton grown in narrow row spacing. In most cases, cotton grown in narrow rows had lint yields equal to or higher than those attained in the 70 cm spacing. modern cultivars in narrow row cotton production did not improve lint yield. No conclusions could be made regarding the impact of plant stature on lint yield. Row spacing had little impact on fiber quality narrow row cotton appeared to be a viable agronomic cotton production practice for the Gonabad compared with conventionally - grown cotton based upon lint yield and fiber quality.

This study aimed to simulate the spatiotemporal variation in cotton (Gossypium hirsutum L.) growth and lint yield using a remote sensing-integrated crop model (RSCM) for cotton. The developed modeling scheme incorporated proximal sensing data and satellite imagery. We formulated this model and evaluated its accuracy using field datasets obtained in Lamesa in 1999, Halfway in 2002 and 2004, and Lubbock in 2003–2005 in the Texas High Plains in the USA. We found that RSCM cotton could reproduce the cotton leaf area index and lint yield across different locations and irrigation systems with a statistically significant degree of accuracy. RSCM cotton was also used to simulate cotton lint yield for the field circles in Halfway. The RSCM system could accurately reproduce the spatiotemporal variations in cotton lint yield when integrated with satellite images. From the results of this study, we predict that the proposed crop-modeling approach will be applicable for the practical monitoring of cotton growth and productivity by farmers. Furthermore, a user can operate the modeling system with minimal input data, owing to the integration of proximal and remote sensing information.

Cotton (Gossypium hirsutum L.) growers are motivated to reduce seeding rates due to increased technology fees associated with improved transgenic cotton cultivars. Advances in planting machinery have improved precision of seed metering and seed placement in recent years. A two-year study was conducted to evaluate the effect of seeding rate, planter downforce, and cultivar on crop emergence and lint yield in cotton planted as singulated and hill-drop (two seed hill-1) configuration. Study treatments consisted of two seeding rates (71,660 and 107,490 seed ha-1), two to three planter downforces (0, 445 and 890 N in 2017; 0 and 890 N in 2018) and two cotton cultivars (representing a large-seeded and small-seeded cultivar, 9,259 - 10,582 and 11,244 - 14,330 seed kg-1, respectively) arranged in a strip-split plot design in both seeding configurations. Crop emergence and lint yield in the middle two rows (four-row plots) were measured to evaluate treatment effects among seeding configurations. Results showed that seeding rate and cultivar did not affect (p>0.05) crop emergence and lint yield in both singulated and hill-drop cotton. Crop emergence varied between the two years due to differences in field tillage conditions. Planter downforce affected crop emergence in singulated cotton but not in hill-drop cotton during both years. Field tillage conditions also influenced downforce effect on crop emergence. Selection of an optimal planter downforce had more significant effect (p<0.05) on singulated cotton than hill-dropped cotton. Results showed that large-seeded cultivars can be utilized to attain a high crop emergence early in the season which can help in minimizing production risks associated with poor stand establishment. High seed and technology fees incurred by growers can be effectively reduced by planting lower seeding rates - given an adequate stand establishment is attained using appropriate planter setup including downforce and cultivar selection.

Optimizing soil health through soil amendments is a promising strategy for enhancing rainwater efficiency for stabilizing crop production. Biochar, obtained by torrefaction of sugarcane bagasse, a byproduct from sugar mills, has a high potential for its use as a soil amendment, which can boost crop yields, but needs further field trials for its adoption in farming systems. A field study was conducted during 2019–2021 at Stoneville, Mississippi, to assess rainfed cotton (Gossypium hirsutum L.) production under four biochar levels (0, 10, 20, and 40 t ha−1) on Dundee silt loam soil. The effects of biochar on cotton growth and lint yield and quality were examined. Biochar levels had no significant impact on cotton lint and seed yield for the first two years. Still, in the third year, a significant increase in lint yield by 13 and 21.7% was recorded at 20 and 40 t ha−1 biochar levels, respectively. In the third year, lint yields were 1523, 1586, 1721, and 1854 kg ha−1 at 0, 10, 20 and 40 t ha−1 biochar levels, respectively. Similarly, cotton seed yield increased by 10.8% and 13.4% in 20 and 40 t ha−1 biochar plots. This study demonstrated that successive biochar applications at 20 or 40 t ha−1 can enhance cotton lint and seed yields under rainfed conditions. These improved yields with biochar did not produce increased net returns due to the increased production costs. Many lint quality parameters were unaffected except for micronaire, fiber strength and fiber length. However, potential long-term benefits of enhanced cotton production from biochar application beyond the length of the study merit further investigation. Additionally, biochar application is more relevant when accrued carbon credits through carbon sequestration outweigh the increased production costs due to biochar application.

65 years of cotton lint yield progress in the USA: Uncovering key influential yield components

There has been limited introduction of new cover crop species into cotton (Gossypium hirsutum L.) production within the last 30 years. Mounting evidence shows that traditional cover cropping species may be detrimental to cotton production, either by depleting soil fertility with crop removal, immobilizing minerals from high carbon residue, or excessive quantity of residue remaining at planting. The objective of this study was to determine the effects of growing a novel cover crop species, carinata (Brassica carinata A. Braun), as a winter annual cover crop for cotton rotation in the southeastern Coastal Plain. Over a 2‐year period, carinata, winter wheat (Triticum aestivum L.), and fallow covers were maintained over winter months, then rotated into cotton. Each year, seedcotton and lint yields were collected, along with subsamples for ginning and subsequent fiber quality analyses. Additionally, end‐of‐season plant mapping was conducted on plants from 1 m of row per plot to determine cover crop effects on boll formation, retention, and distribution, as well as canopy architecture. Results indicated that seedcotton and lint yield of cotton following carinata was greater than cotton following winter wheat, and lint yields of cotton following wheat were lower than cotton after fallow. Fiber quality was largely unaffected by preceding cover crop. End‐of‐season plant mapping indicated that cotton grown after carinata had more position 2 bolls, which correlated to greater lint yields. These results indicate that carinata can potentially serve as a new, more effective cover crop than winter wheat for cotton rotations in Coastal Plain soils.

Interest in short‐season cotton production is increasing because of late‐season insect problems and, in the West, because of the expense of irrigation. Diverse cultivars of Upland cotton (Gossypium hirsutum L.) and American Pima cotton (G. barbadense L.) were compared at Phoenix, Arizona to evaluate short‐season production using several planting dates in 3 years and three dates of final irrigation in one of the years. The soil was a fine‐loamy, mixed (calcareous), hyperthermic, Anthropic Torrifluvents. Lint yield of Upland cotton was not reduced when planted as late as 7 May, except when irrigation was terminated in mid‐August. In contrast, lint yields of Pima cottons were reduced with each later planting date, except for the earliest planting and latest irrigation and harvest. Plant populations in 2 years had no interaction with planting dates for lint yield. The dates of seedling emergence and dates of early flowering occurred about the same time for Upland and Pima cotton in most plantings and therefore could not account for the differences between species in yield response to dates of planting and final irrigation. The rate of flowering, once started, was much slower for Pima cotton than Upland cotton. ‘Pima S‐5’ reached peak flowering an average of 18 days later than ‘Deltapine 61’ (DPL 61). Weekly lint production far DPL 61 was 4.5 times that for Pima S‐5 in August, twice that of Pima S‐5 in September, but only three‐fifths that of Pima S‐5 in October. Pima strain ‘79–106’ was intermediate between DPL 61 and Pima S‐5 in earliness of lint production. We conclude that Pima cotton requires early planting and nearly full‐season production for highest yield. Early planting is not as critical for Upland cotton, unless early crop termination is planned.

ABSTRACTOne option available to cotton (Gosspyium hirsutum L.) producers for control of glyphosate [N‐(phosphonomethyl)glycine]–resistant (GR) weeds is the use of glufosinate [(2RS)‐2‐amino‐4‐[hydroxy(methyl)phosphinoyl]butyric acid] (Liberty 280SL, 24.5% [w/v] glufosinate‐ammonium salt) in glufosinate‐tolerant, transgenic cotton cultivars. A field experiment conducted in 2011 and 2012 in Florence, SC, examined the effects of glufosinate on the growth, lint yield, and fiber quality of WideStrike and Liberty‐Link cotton cultivars. Five WideStrike cultivars and three Liberty‐Link cultivars were sprayed topically at the 1‐ to 3‐leaf stage and the 7‐ to 9‐leaf stage with glufosinate at 0.59 kg ha−1. Glufosinate‐ and weed‐free plots were maintained as controls for each cultivar. Reduced plant health and increased leaf injury were observed in both Liberty‐Link and WideStrike cultivars following glufosinate applications, but sprayed WideStrike cultivars displayed as much as 11% greater leaf injury than sprayed Liberty‐Link cultivars. No differences in lint yield were found between sprayed WideStrike or Liberty‐Link cultivars and their respective controls. However, averaged across all cultivars, lint yield of cotton sprayed with glufosinate was 105 kg ha−1 greater than unsprayed cotton. Yield increases of sprayed cotton appeared to be related to increased boll production at the first fruiting position and between nodes 11 and 15. Glufosinate had no effect on any fiber property evaluated. Cotton producers planting WideStrike or Liberty‐Link cotton cultivars and using glufosinate at labeled rates can adequately control GR weeds without negatively affecting lint yield or fiber quality. Cotton producers may also possibly experience slight lint yield increases as a result of glufosinate application in WideStrike and Liberty‐Link cotton cultivars.

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.

Conservation management practices such as no-tillage and cover crops can decrease soil’s susceptibility to wind erosion, but adoption of these practices has been limited on the Texas High Plains (THP) where producers are concerned with cover crop water usage. The objective of this study was to evaluate the impact of no-tillage and cover crops on cotton (Gossypium hirsutum L.) lint yield and soil water content in a deficit irrigated cropping system. Soil water was observed bi-weekly in long-term, continuous cotton systems established in 1998 that included (1) conventional tillage, winter fallow, (2) no-tillage with rye (Secale cereale L.) cover, and (3) no-tillage with mixed species cover located in Lamesa, TX, USA. Results include observations from 2018–2020 (years 21–23 of the study period). The adoption of conservation practices did not significantly reduce cotton lint yield compared to conventionally tilled, winter fallow cotton. Soil water was initially depleted with cover crops but was greater throughout the growing season following cover crop termination. Throughout the soil profile, water depletion and recharge were more dynamic with conservation practices compared to the conventionally tilled control. There were no differences in cotton water use efficiency between treatments. Results from this study indicate cover crop water usage is likely not the cause of cotton lint yield decline in this deficit irrigated semi-arid production system.