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Cotton (Gossypium sp.) is an important worldwide cash crop that provides a competitive renewable natural fiber supply for the demands of textile industry. The development of new textile technologies and the improvement of living standards increase the demands for both fiber quantity and fiber quality. '0-153' is an upland cotton cultivar with excellent fiber quality derived from Asiatic cotton sources, especially with regards to fiber strength. To identify quantitative trait loci (QTLs) for fiber strength in this line, a recombinant inbred line population consisting of 196 lines was developed from a cross between it and 'sGK9708'. A genetic linkage map consisting of 2393 loci was constructed using this recombinant inbred line population, with single nucleotide polymorphism (SNP) markers from the IntlCottonSNPConsortium_70k chip. Quantitative trait loci for fiber strength were detected across 11 environments using both single-environment and combined multipleenvironment models. A total of 63 QTLs controlling fiber strength were detected by the single-environment model. Sixteen QTLs were identified by the combined multipleenvironment model. These QTLs could make a contribution to the improvement of fiber quality via marker-assisted selection and provide useful information for QTL fine mapping and functional gene research activities as well. [ABSTRACT FROM AUTHOR]

Evaluating germplasm resources comprehensively and accurately is of great significance to their efficient utilization. To comprehensively characterize the genetic relationships among upland cotton (Gossypium hirsutum L.) varieties, the genetic diversity of 172 upland cotton varieties in China was assessed using 18 phenotype traits and 154 polymorphic simple sequence repeat molecular markers. According to the variation analysis of phenotype traits, the variation coefficient, which reflects the level of phenotypic genetic diversity, varied widely among traits. The analysis of marker polymorphism showed that the average allele number, gene diversity index, and polymorphism information content were 2.62, 0.3985 and 0.3343, respectively, indicating a relatively low level of genetic diversity. All varieties grouped into five clusters (I–V) based on phenotypic data. Among the five clusters, clusters III and IV further grouped into four (III-1, III-2, III-3, and III-4) and two subclusters (IV-1 and IV-2), respectively. Cluster I and subclusters III-1, III-3, III-4, and IV-1 displayed prominent values in some of the 18 traits. Then, all varieties grouped into nine clusters (A–I) based on molecular marker data. Clusters C, D, E, F, H, and I displayed prominent values in some of the 18 traits. Clustering based on phenotype traits and/or molecular markers was largely congruent with varietal pedigree information, but the clustering of varieties was independent of the varietal ecological sources. Results in this study suggest that varieties with prominent complementary traits in different phenotype- and/or marker- based clusters can be selected as parents in breeding. [ABSTRACT FROM AUTHOR]

We have previously shown genetic diversity in mature cotton (Gossypium hirsutum L.) pollen sensitivity to low humidity. In vitro studies showed reduced pollen germination and pollen tube growth under low humidity. The present study investigated the impact of pollen sensitivity to low humidity on the amount of outcrossing to neighboring plants. We utilized "red" and "green" pigmented cotton, in addition to gossypol glanded and glandless cotton cultivars, to study pollen movement in the field. Genetic diversity in outcrossing was observed among the six cultivars tested. Differences in outcrossing of 5 to 15% were observed under both irrigated and dryland production systems. Higher levels of outcrossing were observed within a row compared to outcrossing between rows. Cotton cultivars with mature pollen sensitive to low humidity exhibited reduced outcrossing compare to cultivars that were less sensitive to low humidity. These results suggest that cultivars with pollen sensitive to low humidity can be used to reduce natural outcrossing and subsequently adventitious presence in adjacent fields throughout the Southwest. [ABSTRACT FROM AUTHOR]

Stand establishment and early vigor are critical to the successful production of cotton (Gossypium hirsutum L.). Rapid early growth could provide significant advantages to young plants relative to diseases, insects, and weeds. The objectives of this research were to identify traits that contribute to differences in early growth, characterize genotypic variation in early vigor among modern cultivars and advanced breeding lines, and determine the effect of the seed production environment on early vigor. Early growth of 10 genotypes from private companies and 18 unreleased breeding lines was compared through measurements of leaf area and biomass under field conditions in 2 yr. A positive correlation of seed weight and rapid early growth was observed up to 32 d after planting (DAP). Cotyledon area was positively associated with shoot dry weight over the course of the first 52 DAP. Significant genotypic differences were observed for cotyledon and total leaf areas, and for cotyledon, first true leaf, total leaf, stem, and total shoot dry weights in both years within approximately the first 4 wk after planting. No correlation between lint yield and rapid early growth was found. For the first 17 (2009) and 32 (2008) DAP--but not after that--plants grown from seeds produced in distinct environments differed in early vigor. Overall, seeds from breeding lines produced more vigorous seedlings than did seeds of commercial genotypes. Although heritability of the examined traits has not been established, the broad range in values and significant genotypic variation suggest that breeding for enhanced early vigor should be possible without compromising yield. [ABSTRACT FROM AUTHOR]

Genotype × environment interaction (G × E) plays a fundamental role in important agricultural traits such as grain yield or disease resistance. Therefore, modeling G × E is essential for the selection of high yielding and well-adapted varieties. The availability of new sources of genetic and environmental information (e.g., dense panels for molecular markers coupled with large numbers of environmental covariates [EC]) provides important opportunities for studying and exploiting G × E. However, incorporating highdimensional genetic and environmental data and accounting for potential interactions is not an easy task. Recently we developed a genomic model that incorporates molecular markers, EC, and the interactions between them using covariance functions. In this paper we demonstrate how the same approach can be applied in cases where genetic information is based on pedigrees instead of molecular markers. We evaluated the models using a collection of 7809 grain yield records obtained from 582 cotton lines evaluated in 2 yr (2011 and 2012) over nine locations. A total of 76 EC were available and used to model main and interaction effects. Estimates of variance components indicated that G × E explained a sizable proportion of the phenotypic variance, and two cross-validation analyses indicated that modeling G × E increases prediction accuracy by a considerable margin. To the best of our knowledge, this is the first study considering both pedigree and EC for the analysis of cotton yield. The models described here can be used for prediction of genetic merit and for selection for target environments. [ABSTRACT FROM AUTHOR]

One 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. [ABSTRACT FROM AUTHOR]

Extra-long staple (ELS) pima cotton (Gossypium barbadense L.) in the United States is identified by fibers with an upper half mean length (UHML) of at least 34.9 mm. Upland cotton (Gossypium hirsutum L.) traditionally has been referred to as short or medium staple cotton and in 2008 comprised approximately 95% of U.S. production, with pima comprising about 5%. Upland cotton is grown on the majority of acreage devoted to cotton because of its yield potential relative to pima, and its fiber has been adequate for most end uses. However, cotton breeders have long sought to develop upland cotton with the elite fiber quality of pima. Nine upland cotton germplasm lines exhibiting the ELS trait have been developed and released by Texas A&M AgriLife Research. These lines are characterized by improved UHML and fiber bundle strength, average yield, and low lint percent. Improving lint yield potential and lint percent while maintaining the ELS trait in this upland cotton germplasm pool will depend on an understanding of the impact of the ELS trait on yield components. The objective of this study was to evaluate the impact of the upland ELS trait on within-boll yield components when compared with two cultivars of upland cotton and one pima cotton cultivar. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium hirsutum L.) fiber color is influenced by biotic and abiotic factors as well as genetics. After boll opening, exposure to the elements modifies fiber color; fibers may become grayer (excessive moisture leading to biotic activity) and lose luster (lower reflectance). Excessive weathering will lead to poorer processing efficiency and lower dye uptake. Genetically whiter cotton fibers could result in reduced use of bleaching agents before dyeing, thus lowering production costs and providing a more environmentally-friendly product. Cotton cultivars TAM B182-33 ELS (Extra Long Staple) and Tamcot CAMD-E were crossed with 12 cultivars from China, 7 from northern Africa, 10 from southern Africa, and 7 from the United States and grown in a line x tester design at College Station, TX during 2010 and 2011. Seedcotton was harvested by hand on the day of maturity, deburred, and allowed to dry in limited light. Lint was separated into 2-g subsamples, and color measurements were taken using a Konica-Minolta CR-310 reflectance colorimeter. Absolute color measurements were obtained in the CIE L*a*b* color system. General and specific combining abilities for all the variables were determined. Genetic variation existed for all color parameters measured. The cultivars A 7215 (southern Africa), Tejas (United States), PAN 575 (northern Africa), Lintsing Sze Tze 4B (China), F 280 (northern Africa), and Nanging #12 (China) and their F1 progenies demonstrated superior whiteness. PAN 575 was the best general combiner for whiteness with the two testers in the study. [ABSTRACT FROM AUTHOR]

Increased U.S. export of cotton and global competition necessitates that plant breeders continue to improve fiber properties of upland cotton, Gossypium hirsutum (L.). TAM B182-33 ELS (Extra-Long Staple) (Smith, et al., 2009) germplasm line of upland cotton, and 'Tamcot CAMD-E' (Bird, 1979), a short-staple obsolete cultivar, were crossed with 12 cultivars from China, seven from northern Africa, 10 from southern Africa, and seven from the United States. Parents and 72 F1s were grown in College Station, TX, in a Line × Tester design during the summers of 2010 and 2011. Mature, unopened bolls were hand harvested, deburred and allowed to dry in limited light. Maturity ratio (MR) and ribbon width (RbWth) were determined on a Cottonscope at the Fiber and Biopolymer Research Institute (FBRI) in Lubbock, TX on the 38 parents and F1s, and general and specific combining abilities were determined. Genetic variation existed for MR and RbWth among the distinct germplasm pools utilized in this study. 'Allen 333-61 CB 4027' (northern Africa), 'Phytogen 72' (United States), 'UK 64' (southern Africa) and 'Lintsing Sze Tze 4B' (China) and their F1 progenies from crosses with TAM B182-33 ELS and Tamcot CAMD-E had enhanced maturity characteristics, particularly high MR values, indicating that their fibers are more mature than that from some of the other cultivars. Data suggest that MR could be improved through breeding and use of the Cottonscope. [ABSTRACT FROM AUTHOR]

Texas A&M AgriLife Research released several upland cotton (Gossypium hirsutum L.) germplasm lines that exhibit near extra long and extra long staple (ELS) upper half mean length (UHML) fibers, similar to those produced by pima cotton (Gossypium barbadense L.) and significantly longer than those of upland cultivars currently grown in the United States. While present-day global marketing systems do not reward the production of such upland cotton fibers, future competitiveness of upland cotton may depend on availability of such variability. Thirty-six improved upland cotton cultivar accessions from the USDA-ARS Cotton Collection were crossed to two testers to determine if any contained alleles for additional improvement in fiber length or strength parameters of germplasm developed by Texas A&M AgriLife Research. 'Tamcot CAMD-E' was chosen as a standard fiber quality tester and TAM B182-33 ELS was the elite fiber quality tester. The lines, testers, and F1s were grown in Tecoman, Colima, Mexico, and at College Station, TX, in 2010 and at College Station only in 2011. Fiber data were subjected to line × tester analysis. Funtua FT-5 from northern Africa and Stoneville 474 from the United States may harbor additional UHML and length uniformity alleles for improving TAM B182-33 ELS. Phytogen 72 (United States) and BJA 592 (northern Africa) may contain additional alleles to improve fiber bundle strength. [ABSTRACT FROM AUTHOR]

Verticillium wilt (VW) is one of the important damaging cotton (Gossypium hirsutum L.) diseases worldwide. The use of resistant cultivars has long been considered as the most practical and effective means of controlling VW. The upland cotton cultivar Prema has high VW resistance and is useful for breeding new cultivars resistant to VW. To tag the resistance quantitative trait loci (QTL) in this cultivar, a population of 180 recombinant inbred lines was developed via single seed decent from a cross between the resistant Prema and the susceptible cultivar 86-1. Verticillium wilt resistance trials were conducted in the artificial disease nursery inoculated with mixed isolates and greenhouse individually with VW defoliating isolates V991 and VD8 over a 2-yr period. Based on composite interval mapping analysis of the 2010 and 2011 data sets of adjusted disease reaction in the artificial disease nursery, seven resistant QTL were detected. Among them, one major VW-resistant QTL, which explained 62.83% of the phenotypic variation on the average with logarithm of the odds scores ranging from 23.37 to 26.73, was detected consistently and anchored on chromosome (chr.) D9. Greenhouse experiments revealed the existence of five significant QTL on chr. A9, D3, D11, and D9. Our results showed that qVW-D9-1 is a major broad-spectrum VW resistance QTL. Identification of this QTL will facilitate the marker-assisted selection of VW resistance in cotton breeding. [ABSTRACT FROM AUTHOR]

The United States produces approximately 18 million 218-kg bales of cotton (Gossypium spp.) annually. The global market places value on longer fibers, mandating that breeders develop cultivars to meet this demand. Mutation has not been used extensively in upland cotton breeding for improving fiber quality traits. The objective of this study was to determine if treating cotton seeds of a genotype that produces longer fibers than most U.S. upland cotton cultivars with ethyl methanesulfonate (EMS) could result in mutant lines with exceptional fiber quality. TAM 94L-25 (94L-25) (Smith, 2003) (PI 631440) seeds were treated in 2001 with EMS at three times the least dosage to kill 50% of the seeds (LD50). Thirty mutation (M) lines of 94L-25, derived as M3:4 progeny rows, 94L-25 M0, and two check cultivars, FM 832 (Constable et al., 2001) (Plant Variety Protection [PVP] 9800258 or PI 603955) and PSC 355 (PI 612974), were grown in a randomized complete block design with four replications at College Station, TX (CS), and Weslaco, TX (W), in 2008 and 2009. High volume instrument (HVI) fiber properties were determined from hand harvested boll samples. Four M lines exceeded the lint yield of the M0 parent during both years. Fourteen M lines produced longer fibers than the M0 parent and both commercial checks while several M lines exhibited improved strength in 2008 but not in 2009. Treatment of 94L-25 with the chemical mutagenic agent EMS was successful in producing selectable variation for yield and fiber traits simultaneously. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium spp.) fibers are produced primarily by G. hirsutum L, upland, and G barbadense L, pima, or Extra Long Staple (ELS). Two ELS upland lines, developed by Texas AgriLife Research, along with 'FiberMax 832LU (FM 832) and 'DPL Pima HTO' (Pima HTO), were grown in a randomized complete block design at College Station, TX, during 2007 and 2008. Subplots of spindle-harvested seedcotton were ginned on a saw gin or roller gin with appropriate lint cleaning. High-volume instrument (HVI) and Advanced Fiber Information System (AFIS) fiber parameters were determined. Combed 50-Ne (English yarn count) and 80-Ne yarns were produced. Upland ELS lines exhibited longer (p < 0.01) fibers than FM 832, but only TAM B182-33 ELS produced fibers longer or equal (p < 0.01) to Pima HTO. Upland ELS lines produced stronger 50-Ne ring-spun yarns than FM 832 but not Pima HTO, which also produced stronger 80-Ne ring-spun yarn than the upland ELS lines. While roller ginning resulted in significantly higher micronaire, longer upper half mean length, more uniform fiber lengths, and longer upper-quartile length than saw ginning among these genotypes, yarn parameters reported were not affected. All genotypes responded the same to ginning platform, suggesting that further development of the upland ELS trait will not dictate a change in ginning equipment for upland cotton. The upland ELS trait contributes to significantly improved upland yarn quality. [ABSTRACT FROM AUTHOR]

A plant-based thermal optimum approach to irrigation scheduling provides potential benefits in that water applications are scheduled on the basis of plant response to water status. Such irrigation systems require a defined thermal optimum for the crop and while such optimum values have been identified for cotton (Gossypium hirsutum L.) cultivars in the United States, there is no information of this type for cultivars common in Australian production. This paper outlines a threefold approach to determining the optimum temperature (Topt) of the commercial Australian cotton cultivar Sicot 70BRF in an Australian production system. It combines the use of a laboratorybased fluorescence assay, field-based net C assimilation rate (A) and stomatal conductance to water vapor (gs), and canopy temperature (Tc)-yield relations. The fluorescence assay showed a Topt between 28 and 30°C while leaf gas exchange rates peaked at a leaf temperature (TI) of 29°C. The Tc-yield relations peaked at 26°C, with yield reductions observed when Tc > 28°C. We conclude the Topt of the Australian upland cotton cultivar Sicot 70BRF to be 28 ± 2°C. This Topt will provide valuable information for use in thermal optimum irrigation scheduling systems. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to identify how planting date and irrigation regime impact cottonseed composition. The study reveals that the impact of early planting on the distribution of fatty acid was the same to the impact found under dryland conditions. It shows that irrigation and early planting provide potential for improved seed and fiber yield, but with changed seed composition.

One of the most significant, long-term public U.S. Upland cotton (Gossypium hirsutum L.) germplasm enhancement programs is known as the Pee Dee germplasm program. The unique, genetic foundation of the Pee Dee germplasm was created using germplasm from Upland, Sea Island (Gossypium barbadense L.), and primitive diploid cottons. Since the program's inception in 1935, the Pee Dee germplasm program has released >80 improved germplasm lines and cultivars. In this study, the agronomic and fiber quality performance of Pee Dee germplasm was evaluated across southeastern U.S. environments to estimate genetic improvement within the Pee Dee germplasm program. Results suggest that the Pee Dee germplasm enhancement program has (i) maintained usable genetic variation and (ii) maintained high fiber quality potential while concomitantly improving agronomic performance. Although the results highlight the need to continue improving lint percent, lint yield, and bolls m2, there is also evidence to suggest that Pee Dee germplasm can continue being utilized to develop the next generation of high-fiber-quality and high-yielding cotton cultivars. [ABSTRACT FROM AUTHOR]

The cultivated Gossypium spp. (cotton) represents the single most important, natural fiber crop in the world. In addition to its fiber, the oil and protein portion of the cottonseed also represents significant economic value. To protect the worldwide economic value of cotton fiber and cotton byproducts, coordinated efforts to collect and maintain cotton genetic resources have increased over the last 100 yr. The classified genetic resources of cotton are extensive and include five tetraploid species in the primary gene pool, 20 diploid species in the secondary gene pool, and 25 diploid species in the tertiary gene pool. This report provides information on the status and contents of eight major cotton germplasm collections present across the world. Based on the findings of this report, a number of classified Gossypium species are not maintained in these collections, and several are underrepresented and vulnerable to extinction. This report presents several critical challenges and opportunities facing international efforts to enhance and preserve the world's Gossypium genetic resources. Multinational communication and collaboration are essential to protect, secure, and evaluate the global cotton germplasm resources. Without global, collaborative efforts, the rarest and most unique cotton germplasm resources are vulnerable to extinction. [ABSTRACT FROM AUTHOR]

Normal planting of full-season cotton (Gossypium hirsutum L.) (NPF) in saline fields of the Yellow River vaHey, China, is currently faced with poor stand establishment, late maturity, and increasing cost of inputs. Our objective was to determine if late planting of short-season cotton (LPS) may alleviate these problems. In the first experiment, the effects of cultivar, planting date, seeding rate, and their interactions on stand establishment and seedling Na+ and malondialdehyde concentrations were studied. We also compared varietal effects, input costs, and gross economic returns under NPF and LPS. Late planting improved stand establishment due to increased temperature and reduced Na+ and malondialdehyde concentrations in cotton tissues. The LPS at 21 kg seeds ha-1 (LPSM) and NPF at 30 kg seeds ha-1 (NPFH) yielded better than other treatment combinations. Varietal effects on lint yield were not significant. The output value of both systems was comparable; however, the net revenue from LPSM was 32% greater than that from NPFH due to lower material cost and labor inputs. Late planting of short-season cotton is a promising option for cotton production in saline areas of the Yellow River delta and probably in other cotton-growing areas with similar ecologies. [ABSTRACT FROM AUTHOR]

Glyphosate [N-(phosphonomethyl)glycine] herbicide can be topically applied twice at rates as high as 0.84 kg a.e. (acid-equivalent) ha[sup -1] to glyphosate-resistant cotton (Gossypium hirsutum L.) cultivars until the fourth true leaf stage, with the requirement of at least 10 d and two nodes of growth between applications. But, such cultivars are not reproductively resistant to glyphosate applied topically or imprecisely directed after the four-leaf stage because glyphosate can curtail pollen development and ovule fertilization, which potentially reduces yield. Extending glyphosate resistance past the four-leaf stage would provide growers with additional weed management options. Our objective was to test under field conditions glyphosate resistance of cotton germplasm transformed with gene constructs previously shown to impart extended glyphosate resistance in the greenhouse. Four or six transgenic cotton lines containing one of several constructs conferring extended glyphosate resistance, plus the current glyphosate-resistant control ('Coker 312'-1445), were tested at nine U.S. locations in 2001. Within locations, treatment designs consisted of cross-classified arrangements of transgenic lines and glyphosate rates [0, 1.68, and 2.52 kg a.e. ha[sup -1]]. Treated plots received glyphosate over-the-top of cotton at four growth stages (3-, 6-, 10-, and 14-leaf crop stages). Compared with Coker 312-1445, extended glyphosate resistance was expressed as higher yields when glyphosate was applied topically at the four growth stages. Mature plant mapping confirmed extended glyphosate resistance of the new transgenic cotton through similar fruit distribution and weight with or without glyphosate treatment. The capability to apply glyphosate topically to cotton later in crop development will facilitate weed management and could reduce dependence on directed herbicides. [ABSTRACT FROM AUTHOR]

Compares the cotton cultivars, Tamcot and Stoneville 213 to study the plants' photosynthate partitioning patterns. Samples of reproductive growth of the cultivars; Percentage of photosynthate distribution after one year of growing conditions.

Assesses the development of nematode resistance in cotton cultivars by measuring the production of the nematode species, Meloidogyne incognita and Rotylenchulus reniformis. Monitoring of plant growth and fruiting; Nematode reproduction and root galling; Types of cotton cultivars examined; Cultivars manifesting unprecedented level of resistance.

Examines cotton genotypes varying in canopy characteristics in 76-centimeter and 102-centimeter rows. Genotype and insolation interception study in 1991; Effect of row spacing x genotype interaction on lint yield and fiber properties; Effect of mepiquat chloride on PPFD interception of varying genotypes.

Examines the variation in vitamin E content among currently available upland cotton genotypes. Tocopherol content in the seed coat of cotton cultivars; Difference in the levels of alpha- and delta-tocopoherol among cultivars.

The article provides an overview of the registration of MD 15 upland cotton germplasm, which was developed by the U.S. Agriculture Department-Agricultural Research Service and was released in 2005. The variety was derived from FiberMax 832 and MD 51ne Okra. Its characteristics include enhanced fiber quality characterized by high fiber strength and low short fiber content. It may be useful to breeders as a source of high yield potential and fiber quality. Details on yield and agronomic traits, breeding conditions and method, maintenance, and growth habits are presented.

This article presents information about the newly registered two breeding germplasm lines of cotton, Gossypium hirsutum, which are designated as Arkot 9101 and Arkot 9108. The Registration numbers and PI numbers of these two germplasm lines, respectively, are GP-799, P1 638507 and GP-800, P1 638508. These two were released in 2004 by the Arkansas Agricultural Experiment Station. Arkot 9101 and Arkot 9108 were developed using the generalized procedures outlined by the authors. Both lines were derived from crosses made in 1991 with a common parent, the breeding line 8110-27 from which Arkot 8110 was developed by direct selection. The breeding line 8110-27 was derived from a cross of Tamcot SP21S and Pee Dee 6520. The second parents of Arkot 9101 and Arkot 9108 were H1330 and MD32ne, respectively. The two strains were included in 29 replicated field tests at four Arkansas Agricultural Research Station sites in the Mississippi River Delta and compared with ST474 in 1998 to 2000 and PSC 355 in 2001 to 2003. Arkot 9101 and Arkot 9108, reportedly, display good host plant resistance traits.

Reports on the development of MISCOT 8806 cotton by the Mississippi Agricultural and Forestry Experiment Station and release in February 2002. Primary fiber quality advantage of MISCOT 8806; Plant description.

This article reports that the Agricultural Research Service of the U.S. Department of Agriculture and the Mississippi Agricultural and Forestry Experiment Station have released 21 day length-neutral (DN) flowering cotton germplasm lines in 2004. The botanical name of DN flowering cotton is Gossypium hirsutum. The registration numbers for these germplasm lines range from GP-801 through GP-821. A table containing the gerrnplasm release designation, registration number, and P1 number of each line are given here. The procedure for developing the DN flowering germplasm has been outlined by botanist J.C. McCartyand his colleagues in 1979. Each primitive race accession was crossed as male to the day length-neutral donor parent "Deltapine 16" and subsequently, F2 progenies with the DN flowering habit were selected. These progenies were then backcrossed four times to their respective primitive parent and selected for DN flowering habit in the F2 generation following each backcross. Fiber data analyses revealed that most of the DN lines produced short fibers and low percentage fiber elongation.

Features the U.S. registration of the cultivar 'Tamcot Pyramid' cotton, Gossypium hirsutum. Research leading to the development of Tamcot Pyramid; Developers of the cultivar; Characteristics of the cotton cultivar; Results of irrigated trials; Resistance to pests and diseases.