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The esterase enzymes are a major component of insect detoxification systems and play a crucial role in hydrolyzing lots of xenobiotic compounds. Among insect, generalist herbivores can exhibit developed biochemical defences as a result of exposing to a wide range of plant chemical compounds. To overcome this ability, host plants may affect the level of hydrolases in herbivore insects feeding on. To examine this hypothesis, in the present study total esterase activity was investigated in a highly polyphagous whitefly,Bemisia tabaci,reared on six different varieties of cotton,Gossypium hirsutum. Results showed significant differences in esterase activity ofB. tabacifeeding on the host plant varieties. The highest esterase activities were detected in whiteflies feeding on Sk-Tb and Siokra varieties, whereas those whiteflies that feed on Hopicala variety exhibited the least esterase activities. Our findings highlight the important role of host plants in detoxification ability of herbivore insects. The importance of these findings in biology of insect pests and their applications in integrated pest management programmes ofB. tabacihave been discussed in detail. [ABSTRACT FROM PUBLISHER]

A field experiment was conducted on cotton crop to evaluate the effect of farm manure (FM) alone and in combination with the mineral fertilizers. FM was treated with the 1% application of effective microorganism prepared with molasses to enrich the status of FM as FM-Fermented. Cotton Varity Krishma was cultivated in field with treatments viz. control, FM @ 20Mg ha-1, FM-Fermented@ 20 Mg ha-1, ½ NPK+FM (20 Mg ha-1), ½ NPK+ FM-Fermented (20 Mg ha-1) and NPK (175-85-60 kg ha-1). The experiment was laid out according to randomized complete block design with four replications. At flowering stage fully expanded younger leaves were collocated and analysed for N, P and K contents. Growth and yield parameters of cotton like plant height, sympodial branches, no. of boll plant-1, seed cotton boll plant-1 and seed cotton yield kg ha-1 were recorded. Soil was analyzed after the harvest of crop for N, P, K and organic matter contents. Data were analysed statistically. The results of the experiment indicated that application of recommended dose of NPK produced higher seed cotton yield (2660 kg ha-1) and followed by ½ NPK+FM-Fermented (2523 kg ha-1) and differed significantly from other treatments. There was positive increase in the N, P and K concentration in cotton leaves and in soil due to the combined application of ½ NPK+FM-Fermented. [ABSTRACT FROM AUTHOR]

Fusarium wilt is a worldwide disease that affects cotton production. Molecular markers tightly linked to resistance genes can be used for marker-assisted and/or genomic selection. We performed both family-based linkage mapping and population-based association mapping (AM) to detect quantitative trait loci (QTLs) conferring resistance against Fusarium oxysporum f. sp. vasinfectum race 7 (FOV 7) in Upland cotton. To identify QTLs underlying FOV 7 resistance by linkage mapping, three Upland cotton cultivars/lines, Xuzhou 142, Yumian 21 and Shang 9901, were used to obtain the composite cross population, designated as Xuzhou 142/Yumian 21//Xuzhou 142/Shang 9901. A linkage map containing 185 simple sequence repeat loci and 40 linkage groups was constructed with an average distance of 7.5 cM between adjacent markers. Seven QTLs were detected by linkage mapping, explaining 2.9-6.6 % of the total phenotypic variance. We also performed marker-trait AM with the MLM model (Q + K) in a panel composed of 356 Upland cotton cultivars. In total, 27 loci were significantly associated with FOV 7 resistance at the α = 0.01 level (−log P ≥ 2), which were distributed on 16 chromosomes and explained 1.48-12.99 % of phenotypic variation. Three of the 7 QTLs identified by linkage mapping could be detected in AM. We identified the favorable allele for each of the 27 associated loci and investigated the number of favorable alleles in each accession. The results should increase our understanding of the genetic basis of FOV resistance and facilitate future resistance breeding in Upland cotton. [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]

Key message: We report the first complete set of alien addition lines of G. hirsutum . The characterized lines can be used to introduce valuable traits from G. australe into cultivated cotton. Abstract: Gossypium australe is a diploid wild cotton species (2 n = 26, GG) native to Australia that possesses valuable characteristics unavailable in the cultivated cotton gene pool, such as delayed pigment gland morphogenesis in the seed and resistances to pests and diseases. However, it is very difficult to directly transfer favorable traits into cultivated cotton through conventional gene recombination due to the absence of pairing and crossover between chromosomes of G. australe and Gossypium hirsutum (2 n = 52, AADD). To enhance the transfer of favorable genes from wild species into cultivated cotton, we developed a set of hirsutum- australe monosomic alien chromosome addition lines (MAAL) using a combination of morphological survey, microsatellite marker-assisted selection, and molecular cytogenetic analysis. The amphidiploid (2 n = 78, AADDGG) of G. australe and G. hirsutum was consecutively backcrossed with upland cotton to develop alien addition lines of individual G. australe chromosomes in G. hirsutum. From these backcross progeny, we generated the first complete set of chromosome addition lines in cotton; 11 of 13 lines are monosomic additions, and chromosomes 7G and 13G are multiple additions. MAALs of 1G and 11G were the first to be isolated. The chromosome addition lines can be employed as bridges for the transfer of desired genes from G. australe into G. hirsutum, as well as for gene assignment, isolation of chromosome-specific probes, flow sorting and microdissection of chromosome, development of chromosome-specific ''paints'' for fluorochrome-labeled DNA fragments, physical mapping, and selective isolation and mapping of cDNAs for a particular G. australe chromosome. [ABSTRACT FROM AUTHOR]

Improving yield is a major objective for cotton breeding schemes, and lint yield and its three component traits (boll number, boll weight and lint percentage) are complex traits controlled by multiple genes and various environments. Association mapping was performed to detect markers associated with these four traits using 651 simple sequence repeats (SSRs). A mixed linear model including epistasis and environmental interaction was used to screen the loci associated with these four yield traits by 323 accessions of Gossypium hirsutum L. evaluated in nine different environments. 251 significant loci were detected to be associated with lint yield and its three components, including 69 loci with individual effects and all involved in epistasis interactions. These significant loci explain ∼ 62.05% of the phenotypic variance (ranging from 49.06% ∼ 72.29% for these four traits). It was indicated by high contribution of environmental interaction to the phenotypic variance for lint yield and boll numbers, that genetic effects of SSR loci were susceptible to environment factors. Shared loci were also observed among these four traits, which may be used for simultaneous improvement in cotton breeding for yield traits. Furthermore, consistent and elite loci were screened with −Log10 (P-value) >8.0 based on predicted effects of loci detected in different environments. There was one locus and 6 pairs of epistasis for lint yield, 4 loci and 10 epistasis for boll number, 15 loci and 2 epistasis for boll weight, and 2 loci and 5 epistasis for lint percentage, respectively. These results provided insights into the genetic basis of lint yield and its components and may be useful for marker-assisted breeding to improve cotton production. [ABSTRACT FROM AUTHOR]

The dusky cotton bug, Oxycarenus laetus Kirby (Hemiptera: Lygaeidae), is a serious threat to cotton due to early cultivation of Bt cotton. These studies were carried out under laboratory and field conditions to estimate the feeding damage caused by O. laetus to seed weight, seed germination, and lint quality of cotton cultivar Bt-121 at 6 bug densities (0, 5, 10, 15, 20, and 25 adult pairs). The results revealed that seed germination and seed weight decreased, whereas percent reduction in seed germination and seed weight over control increased with increasing bug density. Bug density in the range of 5-25 pairs caused approximately 9.3%-40.7% reduction in seed germination and 7.5%-29.5% reduction in 100-seed weight over control in both laboratory and field trails. The color of lint changed from pure-white to white when bolls were exposed to 10 and 15 pairs of bugs, while it changed to light-yellow and slightly yellow when bolls were exposed to 20 and 25 pairs of bugs, respectively. Bug density had a high negative correlation with percent seed germination and 100-seed weight, while it had a high positive correlation with reduction in seed germination, reduction in 100-seed weight, and lint quality, under both laboratory and field conditions. Bug density explained more than 95% of total variability in seed germination, reduction in seed germination, 100-seed weight, and reduction in 100-seed weight under both laboratory and field conditions; it explained less than 95% (93.2%) of total variability in lint staining under field conditions. These results indicate that reductions in seed weight, seed germination, and lint quality depend upon bug density. Hence, appropriate control measures should be adopted to check consistent increases in the dusky cotton bug population to avoid seed germination and lint quality losses. [ABSTRACT FROM AUTHOR]

An experiment was conducted to determine efficacy of four neonicotinoids viz; nitenpyram 10SL, thiacloprid 480SC, imidacloprid 200SL, acetamaprid 20SL and four traditional insecticides such as profenofos 50EC, methidathion 40EC, bifenthrin 10EC, λ-cyhalothrin 2.5EC at their recommended field doses against sucking insect pests of cotton and their natural enemies on cotton variety Bt-121 at a farmers' field in Multan. The data on post spray number of insect per leaf was taken to find difference among treatments. The results showed that nitenpyram, thiacloprid and imidacloprid were safer to natural enemies and toxic for the sucking pests as compared to conventional insecticides. The range of percent survival of the green lacewings (42.5-87.5 and 37.5-57.5), lady bird beetle (50.0-60.0 and 26.6-46.6) and pirate bug (28.0-60.0 and 24.0-57.0) was in neonicotinoids and conventional insecticide treated plots, respectively. The use of neonicotinoids for compatibility into integrated pest management is discussed. [ABSTRACT FROM AUTHOR]

Allah Din One (A-One) has been bred through hybridization of a local commercial cotton variety FVH-53 and an exotic variety SL[sup -2]23 containing Cry1 Ac Gene MON-531 event. Croö was attempted during 2001 under green house conditions at Allah Din Research Centre, Bahaudin Zakariya University, Multan. The strain was bulked during early 2005 in F7th generation. All developmental work of A-One had been completed before promulgation of National Bio-Safety rules, 2005. After completion of all Micro, Varietals and Zonal Varietals trials, A-One was tested for two consecutive years 2010[sup -1]2 for various preliminary yield, disease, lint characters and confirmation of Bt Gene by Distinctneö, Uniformity and Stability test, Punjab Seed Corporation yield test and National Coordinated Bt. Trial (NCBT). On the bases of over all good performance, A-One was approved by Provincial Seed Council, Punjab and registered by FSC & RD, Islamabad for general cultivation in 2011[sup -1]2. The optimum sowing time of A-One is 1st May to 15th May and 1st week of March for early sowing. The development of A-One strengthened the much needed gene pool for Bt Cotton in the country. [ABSTRACT FROM AUTHOR]

The variation in Bt toxin was measured in three cotton genotypes (MNH-886, FH-142 and FH-Lalazar) at Agricultural Biotechnology Research Institute, AARI, Faisalabad, Cotton Research Station, Sahiwal, Cotton Research Station, Vehari, Pakistan during 2012. The varieties were measured in seed, 20 days old leaf, peduncle of 20 days old leaf, anther, stigma, pedicel, ovary, petals and& bracts, immature stem, mature stem, 15 days old boll, 30 days old boll, fully matured boll, main roots, secondary roots and all leaves from top to downwards position. Seed hasmaximumMaximum Bt toxin protein was measured in seed 14.9 (μg/g fresh weight) followed by leaves (5.18 μg/g) irrespective ofto location and genetic background. All the floral parts including anthers, stigma, pedicel, ovary and petals contained varying magnitude of Bt toxin. No Bt toxin was detected in mature stem, 15 days old boll, 30 days old boll, fully matured boll, main roots and secondary roots. FH-142 had maximum Cry1Ac protein followed by MNH-886 and FH-Lallazar. The expression of Bt toxin was higher at Sahiwal followed by Faisalabad and Vehari. The top most leaf of stem contained maximum amount of Bt toxin in all types of genotypes at all and locations. The Bt toxin gradually decreased in leaves from top to downwards and uptoup to 8th position leaf, it remaineds 2.28 μg/g on fresh weight basis which is sufficient for the control of lepidopteron insects. [ABSTRACT FROM AUTHOR]

Commercial cultivation of glandless cotton (cotton plants with reduced or no gossypol) will widen the utility of cotton seed beyond its present main use as ruminant animal feed, producing higher income for cotton growers in New Mexico and the Beltwide states as a whole. An Upland cultivar of glandless cotton (Acala GLS) developed for California conditions was evaluated in New Mexico and compared to conventional glanded Acala cultivars (Acala 1517-08 and Acala 1517- 99) developed in New Mexico. Four environments (two experimental stations and two commercial farm sites) were selected for testing. Planting was on one m row-spaced beds and irrigation was by furrows and/or sprinklers. A randomized complete block design was used at the research sites (Las Cruces and Artesia, NM), while paired comparisons were used for the commercial farm sites (Anthony and Garfield, NM). The Acala GLS cultivar generally had lower yields (about 12% lower at the research sites) compared to Acala 1517-08. At one of the commercial farm sites, Acala 1517-99 yielded over 50% more than Acala GLS. Fiber quality parameters of the cultivars were very good and within a similar range except for micronaire which was slightly better in the glandless cultivar at the research sites. Location, year and location x year effects were also significant on yield components. This study highlights the need for the development of more adaptable glandless cotton for the New Mexico environment and the need to study seasonal pest pressure for any emerging new insect pests. [ABSTRACT FROM AUTHOR]

Verticillium wilt (VW) of Upland cotton ( Gossypium hirsutum L.) is caused by the soil-borne fungal pathogen Verticillium dahlia Kleb. The availability of VW-resistant cultivars is vital for control of this economically important disease, but there is a paucity of Upland cotton breeding lines and cultivars with a high level of resistance to VW. In general, G. barbadense L. (source of Pima cotton) is more VW-resistant than Upland cotton. However, the transfer of VW resistance from G. barbadense to Upland cotton is challenging because of hybrid breakdown in the F2 and successive generations of interspecific populations. We conducted two replicated greenhouse studies (tests 1 and 2) to assess the heritability of VW resistance to a defoliating V. dahliae isolate and identify genetic markers associated with VW resistance in an Upland cotton recombinant inbred mapping population that has stable introgression from Pima cotton. Disease ratings at the seedling stage on several different days after the first inoculation (DAI) in test 1, as well as the percentages of infected and defoliated leaves at 2 DAI in test 2, were found to be low to moderately heritable, indicating the importance of a replicated progeny test in selection for VW resistance. With a newly constructed linkage map consisting of 882 simple sequence repeat, single nucleotide polymorphism, and resistance gene analog-amplified fragment length polymorphism marker loci, we identified a total of 21 quantitative trait loci (QTLs) on 11 chromosomes and two linkage groups associated with VW resistance at several different DAIs in greenhouse tests 1 and 2. The markers associated with the VW resistance QTLs will facilitate fine mapping and cloning of VW resistance genes and genomics-assisted breeding for VW-resistant cultivars. [ABSTRACT FROM AUTHOR]

Highlights: [•] Combined stress greatly enhanced lipid peroxidation in 84-S in contrast to M-503. [•] Heat stress did not have any additional effect on that of only drought in both cultivars. [•] Tolerant M-503 showed a higher increase in proline content under combined stress. [•] The sensitivity of 84-S may be related with a decreased activity of CAT and POX. [Copyright &y& Elsevier]

Cotton, referred as "The white gold" is an important commercial crop in India and stands third in the world by means of area of cultivation. Cotton plant regeneration from callus by somatic embryogenesis and its efficiency has been improved significantly in recent times. Our primary investigation was on regenerative studies and multiple shoot induction system focusing mainly on meristematic tissues like seedling cotyledonary nodal explants in RAH-9750 cotton cultivar. An attempt has been made to improve the rate of surveillance and growth of regenerated cotton seedlings by bio-inoculant (mainly AMF) treatment under greenhouse conditions. Out of a total seven pure cultures of AMF fungi, R1-R2 have shown maximum mycorrhizal colonization with RAH-9750 (R) and was identified as Glomus mosseae. This variety was also tested with three different bioinoculants i.e., Rhizobium sp. RHPU-7, Azospirillum sp. PPK-27, Bacillus sp. PU-1, apart from AMF R1-R2 in different combinations. The cotton seedlings have shown the best results in single, dual, triple and multiple combinations i.e R+R1-R2, R+R1-R2+Rhizobium, R+R1-R2+Rhizobium+Azospirillum and R+R1-R2+Rhizobium+Azospirillum+Bacillus respectively. The growth of cotton plants (RAH-9750) generated from meristematic tissue culture was found to be increasing significantly when compared with the normal seeds. Similar results were noticed when the same experiment was subjected to the different soil types of Mahabubnagar district. The investigation clearly infers that better yield of cotton RAH-9750 (R) could be achieved by treating the regenerated cotton seedlings with bioinoculants in different combination in various soil types of Mahabubnagar district. [ABSTRACT FROM AUTHOR]

In order to determine the mortality factors in egg and nymphal stages of whitefly, Bemisia (B.) tabaci (Genn.) (Aleyrodidae: Homoptera) on four Bt varieties (AK- 703, MG-6, Sitara-008, FH-114 and one non Bt variety (FH-901). Randomized complete block design was followed for the varieties grown/sown at Entomological Research Area, University of Agriculture, Faisalabad, Pakistan. Mortality factors included prédation, parasitism, dislodgement, in viability and unknown factors in egg and four nymphal stages. Results showed that 4th nymphal stage suffered maximum mortalities. Prédation and dislodgement were the most important parameters of mortalities in B. tabaci. The mortalities in different life stages and cotton varieties are discussed for use of bio-control agents for management of the whitefly. [ABSTRACT FROM AUTHOR]

Episodes of drought stress in upland cotton (Gossypium hirsutum L.) can be detrimental to vegetative growth, yield characteristics, and fiber quality, depending on the specific growth stage drought occurs. Growth, yield, fiber quality, and boll distribution were compared among four cotton cultivars subjected to four growth-stage specific drought periods that were repeated in three studies over 2 yr in West Texas. Drought timings occurred at pinhead square, early bloom, and two periods of stress during peak bloom. Both years of the study were hot and dry, with minimal rainfall during the episodic drought treatments. Yield was not significantly different among cultivars, nor was there a significant cultivar X irrigation interaction related to cotton yield. However, there were differential effects on fiber quality among cultivars subjected to the different episodic drought timings. Drought stress during squaring resulted in significantly shorter plants with fewer nodes; however, yield was comparable to the highest yields among the other drought stress treatments, and fiber quality parameters were significantly improved compared to all other treatments except full irrigation. The early flowering growth stage was the most sensitive to drought stress and produced the lowest yields, the lowest fruit retention, and poor iber quality. Drought events at peak bloom resulted in similar yield losses to those at squaring, but poorer fiber quality. This information may be crucial for producers who either have competing demands for water resources or who want to maximize profits or resources after the occurrence of a drought episode. [ABSTRACT FROM AUTHOR]

Aims: Boron (B) is the most deficient micronutrient in cotton ( Gossypium hirsutum L.). It is generally accepted that B is immobile in cotton phloem, but some cultivars could remobilize the nutrient. In order to further understand B uptake and mobility in various cotton cultivars two experiments were conducted. Methods: In experiment-1, cotton cultivars were grown in B enriched or natural abundance nutrient solutions for 4 weeks and transferred to nutrient solutions ranging from deficient to sufficient in B. In experiment-2 B enriched boric acid was applied to cotton leaves and B mobilization was determined. Results: In deficient plants, B previously supplied to roots was remobilized from older to younger plant tissues, but the amount was insufficient to maintain growth. Boron deficiency symptoms appeared and progressed with time. Boron applied to leaves was taken up and remobilized within 24 h. Boron mobilization was higher to plant parts above the treated region. Conclusion: Boron uptake and mobilization was similar among cotton cultivars. Boron applied to cotton leaves shows a preferential translocation to younger tissues. Foliar sprays of B to cotton may be used to cope with a temporary deficiency, but to achieve full growth and development B must be available to cotton throughout the plant cycle. [ABSTRACT FROM AUTHOR]

Key message: Genetic diversity and population structure in the US Upland cotton was established and core sets of allelic richness were identified for developing association mapping populations in cotton. Abstract: Elite plant breeding programs could likely benefit from the unexploited standing genetic variation of obsolete cultivars without the yield drag typically associated with wild accessions. A set of 381 accessions comprising 378 Upland ( Gossypium hirsutum L.) and 3 G. barbadense L. accessions of the United States cotton belt were genotyped using 120 genome-wide SSR markers to establish the genetic diversity and population structure in tetraploid cotton. These accessions represent more than 100 years of Upland cotton breeding in the United States. Genetic diversity analysis identified a total of 546 alleles across 141 marker loci. Twenty-two percent of the alleles in Upland accessions were unique, specific to a single accession. Population structure analysis revealed extensive admixture and identified five subgroups corresponding to Southeastern, Midsouth, Southwest, and Western zones of cotton growing areas in the United States, with the three accessions of G. barbadense forming a separate cluster. Phylogenetic analysis supported the subgroups identified by STRUCTURE. Average genetic distance between G. hirsutum accessions was 0.195 indicating low levels of genetic diversity in Upland cotton germplasm pool. The results from both population structure and phylogenetic analysis were in agreement with pedigree information, although there were a few exceptions. Further, core sets of different sizes representing different levels of allelic richness in Upland cotton were identified. Establishment of genetic diversity, population structure, and identification of core sets from this study could be useful for genetic and genomic analysis and systematic utilization of the standing genetic variation in Upland cotton. [ABSTRACT FROM AUTHOR]

The new variety CIM-608 has been developed through interspecific hybridization i.e. 2 (Gossypium hirsutum × G. anomalum) × 3G. hirsutum. at Central Cotton Research Institute, Multan. The variety produced significantly higher yield in varietal trials compared with standard variety i.e. MNH-786. CIM-608 was also evaluated in varietal and Zonal Varietal Trials at farmers' fields and Govt. Farms. In varietal trials CIM-608 gave 33.7%, and 8.97% more yield over commercial varieties MNH-786 and CIM-554, respectively for seed cotton yield. While in Zonal varietal trial during 2010-11, CIM-608 gave 2828 Kg ha-1 yield of seed cotton as compared to standard variety CIM-554 (2600 Kg ha-1). In National Co-ordinated Varietal Trial (NCVT), CIM-608 dominated over most existing varieties/strains in two consecutive years i.e. 2010-11 and 2011-12 for seed cotton yield. This variety showed tolerance to Burewala Strain of cotton leaf curl virus (BSCuV). CIM-608 has combination of characters including CLCuV tolerance, earliness, and heat tolerance with good fibre characteristics. The presented variety of G. hirsutum L. will significantly contribute in the cotton industry of Pakistan. [ABSTRACT FROM AUTHOR]

In present study fifteen varieties of cotton (FH-114, Bt-121, SLH-336, Kirn, SLH Bt-6, Bt-666, CIM-595, FH-113, Bt- MK2, Bt-222, Bt-457, Bt-7, SLH-317 and Bt-986) were cultivated in research area of the Department of Plant Pathology University of Agriculture Faisalabad during 2012 to determine their genetic response against bacterial blight under randomized complete block design (RCBD). Results showed that none of variety showed immune response against disease while FH-114, Bt-121 and SLH-336 showed moderately resistance to bacterial blight with 15, 17 and 20% disease incidence respectively. While Kirn, SLH Bt-6, Bt-666, CIM-595, FH-113 and Bt-MK2 showed moderately susceptible behavior with (29-38%) disease incidence. The varieties SG-1, Bt-222, Bt-457, Bt-7, SLH-317 and Bt-986 showed highly susceptible response with (41-56%) disease incidence against the disease. [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]

Antimicrobial effect is derived from nanosilver particles (diameter between 1 and 100 nm) which are adhered to the fibers. The cotton materials showed antimicrobial effects by killing and/or suppressing growth of a broad spectrum of micro bes such as Esche richia coli, Staphylococcus aurues bacteria and Aspergillus nigera fungi depending on the surface structure of the cotton sample. The present investigation was carried out using the cotton variety Giza 86, to study the effect of nano-silver application on the cotton quality and antimicrobial resistance from raw to fabric. The results indicated that nano-silver application did not affect fiber ribbon width, single fiber linear density and fiber length parameters. While, nano- silver application increased micronaire reading , both of single fiber and bundle strength, yarn mechanical properties and fabric strength. In contrast, it decreased fiber reversals number, convolution number , convolution angle, both of single fiber and bundle elongation, fabric moisture regain and fabric air permeability. The effect of the nano application was reflected positively on the zones of growth inhibition of yarn cotton followed by fabric then raw cotton. Escherichia coli gave the highest diameter of the inhibition zone. On the contrary, Staphylococcus aurues gave the lowest zone. [ABSTRACT FROM AUTHOR]

The populations of the spider mites Tetranychus urticae Koch (different stages), and their natural enemies i.e. predacious mites (families, Stigmaeidae, Tydeidae and Phytoseiidae) and the true spiders (families Saltisidae, Philrodomidae, Miturigidae, Thomisidae, Lycosidae and Araneidae) were studied in Beni Suef governorate during the cotton cultivated seasons, 2010 and 2011.The population differed according to the different sampling dates on the different cotton varities, Giza 80, 90 × ost, Dandra, Giza 83, Giza 89, Giza 90 and Giza 91 varities.The cotton (Giza 90 variety) was the most susceptible to the spider mite infestation in the two seasons, as, it harboured 96.625 and 83.5 mite individuals, per leaf in the seasons 2010 and 2011,respectively. The statistical analysis of obtained data indicated that the least significant differences for different varities were 39.559 and 19.779 in case of season effect. Also, Giza 80 and Giza 83 varities harboured more predacious mites during 2010 (6.5) individuals for each, while each of Giza 80 and Giza 90 harboured during 2011, 6 predacious mites. The average collected numbers of the spiders was 12.25 individuals on Dandra variety during 2010 while on Giza 83 variety during 2011 season was 8.25 individuals. The study indicated that there was generally positive correlation between the two spotted spider mite and their associated natural enemies. [ABSTRACT FROM AUTHOR]

This investigation was carried out to evaluate heterosis, combining ability, gene action and heritability of yield component traits for three commercial cotton varieties G90, G85 and G92 as female and three genotypes as male (G83× "G75×5844"), (G77×G70) and (G89×PimaS6) using line × tester analysis. Results indicated that mean squares due to all 15 genotypes including parent s and crosses were highly significant for all studied traits indicating the presence of sufficient genetic variability in this population. It was also found that parents vs. crosses mean squares as e×pressed to average heterosis over all crosses were highly significant for lint percentage and seed inde×. The mean performance of parents and their F1's hybrids gave a wide range of variation for all studied traits . Heterotic values over the mid - and the better - parent varied between positive or negative significance and highly significant for most of the studied traits. The estimates of variance due to SCA were positive and higher in magnitude than the variance of GCA for all studied traits indicating that the non - additive genetic effect played a major role in the genetic e×pression of these traits. While, additive effects had a minor role in the inheritance of these traits indicating that the hybridization program would be effective in improving yield and its components traits. Comparing the GCA effects of individual parent revealed that G83×(G75×5844) was the best combiner for all studied traits. Dominance estimates were higher than the additive estimates for all studied traits indicating more importance for dominant gene effect in the inheritance of these traits. Estimates of heritability in both broad and narrow senses for yield and its components showed high heritability values in broad sense were detected for all traits under investigation . [ABSTRACT FROM AUTHOR]

In the present study, an attempt has been made to investigate the bio-bleaching preparation of Egyptian cotton fibers. Bleaching of the fibers was performed with hydrogen peroxide,which was enzymatically produced by glucose oxidase during oxidation of D-glucose. The results obtained were compared with the conventional processing method. Promising results have been reported by Glucose Oxidase enzyme (Gox) that converts glucose to hydrogen peroxide and gluconic acid used for bleaching purpose. The gluconic acid produced is a good chelator and can be used as a sequestering agent for metal ions. This is so-called Indirect Enzymatic Bleaching Process and the whiteness degree obtained was acceptable compared with conventional chemical method. The mechanical properties such as tensile strength and elongation of cotton fibers showed no major influence using Gox compared with the conventional method. [ABSTRACT FROM AUTHOR]

Upland cotton ( Gossypium hirsutum L.) hybrids display commercially useful levels of heterosis for lint yield. Cotton lint yield is primarily a multiplicative product of boll number and lint per boll, both of which can be further dissected into sub-components. Relationships among the yield components are complex where they further interact with the environment. To identify different yield components of hybrid cotton lint yield and their relationship with environment, three cotton varieties, DP51, STV474 and LA887 and, their respective hybrids were evaluated for lint yield components across five environments. Heterosis was observed for lint yield as well as yield components. The relationship between heterosis and mean environmental yield was negative for two hybrid combinations, whereas one hybrid showed increased heterosis from low to high yielding environments. Boll number was the major yield component contributing to lint yield. However, yield components contributing to the change in heterosis from low to high yielding environments were different for the three hybrids. The change in lint yield heterosis across environments was correlated with lint per boll and lint per seed for DP51 × STV474 and LA887 × DP51. Whereas, bolls number and boll retention were the main yield components contributing to higher lint yield heterosis of STV474 × LA887 in low yielding environments. Results also reveal effects of parental entries on lint yield as well as relationship of heterosis and environment. [ABSTRACT FROM AUTHOR]

Cotton is a high-value per acre crop that is produced as a raw material for the textile industry. With the development of new technologies in the textile industry, much attention has been paid to fiber quality in conjunction with yield. The introgression cultivar “Acala Prema” is extensively planted in the Carolina/USA for its good fiber qualities, high yields and tolerance to Verticillium wilt. To conduct QTL mapping for fiber quality and yield in Acala-Prema, we developed a population of 180 recombinant inbred lines (RILs) from a single seed derived from a cross between this line and Chinese cultivar 86-1. We examined the yield performance of the RILs in five Chinese environments and fiber qualities in seven Chinese environments. A genetic linkage map comprising 279 loci was constructed using this RIL population, chiefly with SSR markers, and QTLs were repeatedly identified across diverse environments using the composite interval mapping method. A total of 86 nonredundant QTLs for yield and its components and fiber qualities were independently detected in five or seven environments; Prema alleles were responsible for the increase in trait values for 46 QTLs, while 86-1 was responsible for 40 QTLs. Notably, we detected the stable fiber strength QTL qFS- D3- 1, which explained 4.51–17.55 % of PV, with LOD scores ranging from 2.83 to 7.09, and the fiber length qFL- D11- 1, which explained 10.02–25.34 % of the PV. Eighteen environment epistatic QTLs were also detected. The QTLs detected in this study provide new information for improving fiber quality and may be especially valuable for marker-assisted selection. [ABSTRACT FROM AUTHOR]

Exploring the elite alleles and germplasm accessions related to fiber quality traits will accelerate the breeding of cotton for fiber quality improvement. In this study, 99 Gossypium hirsutum L. accessions with diverse origins were used to perform association analysis of fiber quality traits using 97 polymorphic microsatellite marker primer pairs. A total of 107 significant marker-trait associations were detected for three fiber quality traits under three different environments, with 70 detected in two or three environments and 37 detected in only one environment. Among the 70 significant marker-trait associations, 52.86% were reported previously, implying that these are stable loci for target traits. Furthermore, we detected a large number of elite alleles associated simultaneously with two or three traits. These elite alleles were mainly from accessions collected in China, introduced to China from the United States, or rare alleles with a frequency of less than 5%. No one cultivar contained more than half of the elite alleles, but 10 accessions were collected from China and the two introduced from the United States did contain more than half of these alleles. Therefore, there is great potential for mining elite alleles from germplasm accessions for use in fiber quality improvement in modern cotton breeding. [ABSTRACT FROM AUTHOR]

Correlation of the qualitative traits like flower shape, boll colour and boll shape was analysed with the yield and fibre quality traits. Ten varieties were crossed. Parents along with hybrids were sown in field in the research area of Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad. Studies revealed that tubular flower shape showed negative association with green boll colour and ovate boll shape. Green boll colour had negative correlation with ovate boll shape. The qualitative traits like flower shape, boll shape and boll colour also act as markers for selection of polygenic traits like fibre quality and boll characteristics. Dark green boll colour showed positive association with plant height, number of bolls per plant, boll weight, number of locales and fibre strength. Green boll colour negatively correlated with tubular flower shape. Round boll shape had positive correlation with number of sympodial branches and boll weight. Ovate boll shape had negative association with fibre fineness and fibre strength. Tubular flower shape had negative association with plant height, number of sympodial branches, number of monopodial branches, number of bolls per plant, boll weight, and number of locules, GOT%, fibre fineness and fibre strength. Bell shape of flower had positive association with staple length. The association of quality with yield contributing traits may be helpful in future for the development of varieties. [ABSTRACT FROM AUTHOR]

Legacy of seed cotton yield and other quantitative traits is highly persuaded by environmental aspects, therefore, phenotypic response of a genotype is ascertained by genetic and environmental factors upon it, although occurrence of a third effect, of no less importance i.e. genotype-by-environment interaction (GEI). Studies were conducted in 2010 and 2011 evaluating G × E interactions and correlation in upland cotton using randomized complete block design at the University of Agriculture, Peshawar, Pakistan. The GEI was characterized using eight upland cotton cultivars viz., SLH-284, CIM-446, CIM-473, CIM-496, CIM-499, CIM-506, CIM-544 and CIM-707. Significant (p≤0.01) mean squares for genotypes, environments and G × E interactions revealed genetic variability among cotton genotypes as well as environments inconsistency. The contribution to the total sums of squares, regardless of trait, revealed that genotypes and genotype × environment play principal role followed by environments, while replications (experimental error) share was minimal. The environment accounts for 61.86%, 26.99% and 18.64% of total variation for bolls plant-1, seed cotton yield and sympodia plant-1, respectively, considering the larger effects of environment in combination with genotypes on plant growth and morphology. Seed cotton yield has significant (p≤0.01) positive correlation with boll number, and positive with morphological traits. Based on two-year studies, CIM-496 exhibited the best performance followed by CIM-554 and SLH-284 for improvement in seed cotton and lint yields. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop an improved model for describing the accumulation of aboveground cotton biomass. The model input was RTEP, which was the normalized product of thermal effectiveness and photosynthetically active radiation. The model was calibrated using data from field plots with five N rates and two cotton cultivars. Model validation was conducted using data from three independent cotton fields. Eight nonlinear functions described cotton growth well (R>0.0.894, SD<0.05). The parameters of the functions were then compared and the results indicated that the Richards function best fit the nonlinear relationships in a biologically meaningful way. The equation was as follows: relative aboveground biomass accumulation (RAGBA) = 1.024/(1+e6.646-10.115RTEP)1/1417 (r = 0.981, s = 0.043). Validation results indicated that the root mean square error was 0.659 t hm-2, the relative error was 5.337%, the coefficient of concordance was 0.988, and the coefficient of determination was 0.961. The second derivative of the optimized model showed that in cotton, the process of aboveground biomass accumulation could be divided into three phrases using two inflection points. When the accumulation rate of the aboveground biomass of cotton was at its maximum, the relative product of thermal effectiveness and PAR was 0.622, the maximum rate of the aboveground biomass accumulation was 2.299, and the aboveground biomass accumulation was 0.549. In conclusion, our study indicates that the product of thermal effectiveness and PAR is a valuable parameter for estimating aboveground biomass accumulation in cotton. [ABSTRACT FROM AUTHOR]

For better understanding of the adhesive properties of different fractions of cottonseed protein, cottonseed meals from both glanded and glandless cotton varieties were separated into several fractions. Each meal was sequentially extracted with water and 1 M NaCl solution, or with phosphate buffer and NaCl solution. Adhesives were prepared from the recovered fractions and hot-pressed onto maple veneer strips and tested for their properties. The adhesive strength of the water- and buffer-washed solid fractions (i.e., the un-extractable residues of the meals) from the glanded seed ranged from 1.32 to 1.62 MPa and were unchanged or increased compared with the adhesive strength of the original meal that varied from 0.98 and 1.49 MPa. Soaking the wood specimens bonded at 80 °C revealed that the water resistance of these water- and buffer-washed adhesives was significantly improved in that they exhibited no delamination during soaking compared with the meal adhesive that showed some delamination (20-30 % of the samples). Furthermore, the water resistance of these fractions with wet shear strength around 1.5 MPa was comparable to that of cottonseed protein isolate (>90 % protein) when the joints were bonded at 100 °C. The preparations from glandless cottonseed meals showed similar adhesive performances. Additional extraction of the meals with NaCl solution reduced adhesive performance. The results suggest that water- or buffer-washed cottonseed meal fractions can be used as wood adhesives and would be less costly to prepare than cottonseed protein isolates. [ABSTRACT FROM AUTHOR]

During meiosis in microsporogenesis in spermatophytes and in sporogenesis in bryophytes and ferns, regular rearrangement of cytoplasmic organelles (chondriokinesis) occurs. In the present paper, the course of chondriokinesis has been analysed in several representatives of the family Malvaceae (Gossypium arboreum, Alcea rosea and Lavatera thuringiaca). It was revealed that cell organelles in all the species analysed aggregated around the nucleus at the end of prophase I, and next they surrounded two nuclei in telophase I. This position persisted not only until the end of meiosis, but also in post-meiotic cells after formation of microspore sporoderm on mononuclear pollen grains. Currently, this type of cell organelle aggregation has not been reported from other plant groups, and it seems to be characteristic of the representatives of the family Malvaceae only. The role of this type of cell organelle rearrangement still requires elucidation. The current theories are concerned with dividing cells, whereas the cell organelle aggregation described in the present work was observed in post-meiotic cells as well, i.e. in mononuclear pollen grains [ABSTRACT FROM AUTHOR]

Highlights: [•] Found novel cotton germplasm of host plant resistance to silverleaf whitefly. [•] Okra leaf traits reduced adult preference. [•] Glabrous leaf traits which reduced oviposition preference. [•] Alternative traits (biochemical) in G. arboreum reduced immature development and/or survival. [•] These traits could be candidates for developing whitefly-resistant upland cotton cultivars. [Copyright &y& Elsevier]

Small hairs on leaves and stems also known as trichomes are biologically an important insect resistant trait in cotton. Variations in form, function and distribution of hairs within a species have been exploited for developing insect resistant cotton cultivars. The DNA marker for the velvet hairiness trait was identified by RAPD technique using bulked segregant analysis. A cross of velvet hairy (densely hairy) and sparsely hairy genotypes was made and segregating F2 generation was developed for DNA marker studies. Out of the 320 RAPD primers used, 36 showed polymorphism between the parents. The primer, GLG-6975 showed tight linkage with velvet hairy trait in the F2 population. This RAPD marker may be used in molecular breeding of cotton for insect resistance. [ABSTRACT FROM AUTHOR]

Abstract: Agricultural crops experience diverse mechanical stimuli, which may affect their growth and development. This study was conducted to investigate the effects of mechanical stresses caused by hanging labels from the flower petioles (HLFP) on plant shape and cotton yields in four cotton varieties: CCRI 41, DP 99B, CCRC 21, and BAI 1. HLFP significantly reduced plant height by between 7.8% and 36.5% in all four lines and also significantly reduced the number of fruiting positions per plant in the CCRI 41, DP 99B and CCRC 21 lines. However, the number of fruiting positions in BAI 1 was unaffected. HLFP also significantly reduced the boll weight for all four cultivars and the seed cotton yields for CCRI 41, DP 99B and BAI 1. Conversely, it significantly increased the seed cotton yield for CCRC 21 by 11.2%. HLFP treatment did not significantly affect the boll count in the fruiting branches of the 1st and 2nd layers in any variety, but did significantly reduce those on the 3rd and 4th fruiting branch layers for CCRI 41 and DP 99B. Similar trends were observed for the number of bolls per FP. In general, HLFP reduced plant height and boll weight. However, the lines responded differently to HLFP treatment in terms of their total numbers of fruiting positions, boll numbers, seed cotton yields, etc. Our results also suggested that HFLP responses might be delayed for some agronomy traits of some cotton genotypes, and that hanging labels from early-opening flowers might influence the properties related with those that opened later on. [ABSTRACT FROM AUTHOR]

Linkage disequilibrium based association mapping is a powerful tool for dissecting the genetic basis underlying complex traits. In this study, an association mapping panel consisting of 356 representative Upland cotton cultivars was constructed, evaluated in three environments and genotyped using 381 SSRs to detect molecular markers associated with lint yield and its components. The results showed that abundant phenotypic and moderate genetic diversities existed within this germplasm panel. The population could be divided into two subpopulations, and weak relatedness was detected between pair-wise accessions. LD decayed to the background (r2 = 0.1182, P≤0.01), r2 = 0.1 and r2 = 0.2 level within 12–13 cM, 17–18 cM and 3–4 cM, respectively, providing the potential for association mapping of agronomically important traits in Chinese Upland cotton. A total of 55 marker-trait associations were detected between 26 SSRs and seven lint yield traits, based on a mixed linear model (MLM) and Bonferroni correction (P≤0.05/145, −log10P≥3.46). Of which 41 could be detected in more than one environment and 17 markers were simultaneously associated with two or more traits. Many associations were consistent with QTLs identified by linkage mapping in previous reports. Phenotypic values of alleles of each loci in 41 stably detected associations were compared, and 23 favorable alleles were identified. Population frequency of each favorable allele in historically released cultivar groups was also evaluated. The QTLs detected in this study will be helpful in further understanding the genetic basis of lint yield and its components, and the favorable alleles may facilitate future high-yield breeding by genomic selection in Upland cotton. [ABSTRACT FROM AUTHOR]

Expression of Bt gene in cotton is affected by various environmental factors. The objective of the current study was the detection and quantification of Bt endo-toxins in local Pakistani cotton genotypes in various plants under different salt stress levels in various plant parts. Detection of Bt gene type was performed by immune strip analysis while, quantification of Bt toxin was carried out by commercially available ELISA kits. Ten transgenic cotton genotypes of local origin were assessed for the detection of Cry1Ac, Cry1F and Cry2Ab genes. Immunostrip analysis for all Bt cotton genotypes revealed the presence of only Cry1Ac gene. PCR result confirmed the presence of only Mon531 (non-patented) event of 346 base pair amplicon size and ruled out the presence of any other patented event in Pakistani Bt cotton varieties. The toxin value show highly significant differences under different salt stress levels. Bt toxin values were inversely affected by the increase in salinity levels. Bt toxin values tend to decrease after 90 days of sowing in all treatments. Moreover, higher values on fresh weight basis were noted in leaf tissues followed by square tissues. [ABSTRACT FROM AUTHOR]

Although genotypic and environmental contributions to yield and fiber quality have been studied extensively in cotton for decades, the near-constant release of commercially available genotypes necessitates re-evaluation for specific cotton production regions. Consequently, lint yield, lint percent, fiber length, fiber strength, fiber micronaire, and uniformity index were evaluated for seven commercially available cotton cultivars across 33 yield environments in on-farm trials throughout Georgia. The following were quantified: the percentage of variability in each response variable accounted for by genotype and environment, trait stability for each cultivar across all yield environments, and genotypic and environmental correlations between all parameters of interest. Environment was the dominant factor governing lint yield (96.1% environment, 1.2% genotype), fiber length (80.6% environment, 5.1% genotype), strength (47% environment, 27.7% genotype), micronaire (63.8% environment, 9.9% genotype), and uniformity (69.8% environment, 6.5% genotype). In contrast, lint percentage was impacted more by genotype (51.5%) than by environment (38.8%). 'PHY 565 WRF' was identified as the most stable cultivar across all yield environments for all agronomic and fiber quality traits examined. Environmental correlations showed that fiber length, strength, and uniformity were all positively correlated with yield. These findings suggest that any improvements in the yield environment brought about through improved production practices or favorable environmental conditions will be conducive to improving fiber quality in cotton. [ABSTRACT FROM AUTHOR]

Highlights: [•] Biomass, diameter, volume and area significantly inhibited in all cultivars at 1000μM Cd. [•] Subcellular changes were found in nucleus, vacuoles, mitochondria and chloroplast. [•] Ultrastructural alterations were greater in BR001 followed by GK30 and Coker 312. [•] Greater incline in SOD activity occurred in leaves of BR001 and GK30 at 1000μM Cd. [•] POD activity in roots of BR001 and Coker 312 was greater at all Cd levels. [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]

During the past 9 yr, a new race of Fusarium (Fusarium oxysporum f. sp. vasinfectum [FOV Race 4]) has increasingly impacted cotton (Gossypium spp.) in the San Joaquin Valley of California. To assess the vulnerability of upland cotton (G. hirsutumL.) in California to FOV disease, elite upland germplasm lines from 13 U. S. public breeding programs across the Cotton Belt and commercial cultivars were evaluated for disease resistance to FOV Races 1 and 4. Ten independent replicated field trials were conducted: three in 2008, four in 2010, and three in 2011. Significant differences (P ≤ 0.05) were observed for disease severity index of leaves, vascular root staining, and plant survival values among the elite germplasm lines in all 3 yr for the levels of resistance--response to FOV Races 1 and 4. Also, significant interactions among germplasm lines, FOV races (1 and 4), and evaluation sites indicated that germplasm lines differed in mechanisms of plant-defense response for the two FOV races. Selected lines from programs in the states of Alabama, Arkansas, Louisiana, and Mississippi showed at least a moderate level of tolerance to both FOV races; however, several of these lines produced weak and coarse fibers. Based on these evaluations, many of the entries in public breeders' current elite upland germplasm pools may be more susceptible than expected to some FOV races, and sources of acceptable levels of resistance may be limited when tested under infestation levels that resulted in only 5 to 35% plant survival in susceptible check cultivars. [ABSTRACT FROM AUTHOR]

Five cultivars of cotton i.e., 'IR4-NIBGE', 'IR5-NIBGE', 'Bt-121', 'Sitara-10M' and 'Sitara-11M' were screened for resistance against insect pest complex and Cotton Leaf Curl Virus (CLCuV) incidence in the research area of Cotton Research Station, Multan. The result depicted that the most resistant variety against jassids was 'IR4-NIBGE' and 'Sitara- 11M' whereas 'IR4-NIBGE' showed the maximum resistance against whitefly infestation. The least susceptible variety to the infestation of thrips was 'Sitara-10M'. The most susceptible variety to the prevalence of Red Cotton Bug (RCB) was 'IR4- NIBGE'. The genotype 'Bt-121' showed the attack of spotted bollworm. The high population of Dusky Cotton Bug (DCB) was observed on 'Bt-121' throughout the season. The incidence of virus percentage increased with the passage of time; however, the variety 'IR5-NIBGE' exhibited maximum level of tolerance. Variety 'Bt-121' gave the maximum yield i.e., 1852 kg per acre followed by 'IR5-NIBGE', 'Sitara-11M', 'Sitara-10M, 1584, 1503, 1466 kg per acre respectively. Our results suggest that IR4-NIBGE and Sitara -11M are comparatively tolerant to jassids and whitefly which are the yield losing pest. So IR4-NIBGE and Sitara -11M varieties can be included in IPM programme for the management of these voracious pests. [ABSTRACT FROM AUTHOR]

Abstract: A highly sensitive and selective differential pulse voltammetric (DPV) method based on the oxidation of caffeic acid in a glassy carbon electrode is presented for determination of total phenolic acids (TPAs). Under optimized conditions (0.2M phosphate buffer, pH 3, 50mV pulse amplitude, 50mVs−1 scan rate), the oxidation peak current (Ipa) of caffeic acid is linear (Ipa(A)=−4.15×10−8 +0.97 [Caffeic acid]) to caffeic acid concentration in the range from 1.0×10−7 to 1.0×10−6 M, with a correlation coefficient of 0.9985. The detection and quantitation limits obtained were 6.8×10−8 M and 1.0×10−7 M, respectively. The repeatability and intermediate precision of DPV method were acceptable (Relative Standard Deviation (RSD) <10%). The absence of the matrix effect on the determination of TPAs by DPV method was attested by F-test and t-test (95% confidence level). The method was successfully applied to the determination of TPAs in five cotton cultivars, with recoveries of 94–104% (RSD <2%). [Copyright &y& Elsevier]