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1.
Ying Yong Sheng Tai Xue Bao ; 30(9): 3137-3144, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31529889

RESUMO

The objective of this study was to evaluate the effects and underlying physiological mecha-nisms of partial root zone irrigation (PRI) and rational close planting, as well as their interaction on yield and water productivity (WP) of cotton and to explore new alternatives of water-saving irrigation in dry land areas. A factorial field experiment with irrigation mode (normal irrigation, partial root-zone irrigation and deficient irrigation) and plant population density (135000, 180000 and 225000 plants·hm-2) was conducted in the west of Inner Mongolia to examine their effects on cotton growth, yield, water productivity and related physiological characters. The results showed that the irrigation mode and plant density as well as their interaction significantly affected the biomass, yield, yield components and harvest index. Under normal irrigation, the biomass and the number of bolls per unit area increased with the increasing of plant density, but the harvest index and boll weight significantly reduced. The yield of high plant density was comparable to that of medium plant density, both of which were increased significantly compared with that of low plant density. The content of abscisic acid (ABA) significantly increased and that of auxin (IAA) significantly reduced in cotton leaves under partial root-zone irrigation, which significantly increased the harvest index by improving the partitioning of assimilates to reproductive organs under partial root-zone irrigation. The number of bolls per unit area increased and boll mass remained unchanged with the increasing of density under partial root-zone irrigation. The yield of high density increased by 6.7% and 11.5% compared with that of medium and low density under partial root zone irrigation. The pre-frost seed cotton increased by 22.5%, the amount of irrigation reduced by 30%, and water productivity increased by 49.3% under partial root zone irrigation compared with that under normal irrigation at high plant density. Plant density did not affect photosynthetic rate (Pn) of functional leaves, but irrigation mode significantly affected Pn. Deficient irrigation significantly reduced the Pn of the main-stem functional leaves, but the Pn under partial root-zone irrigation was comparable to that of normal irrigation. The jasmonate (JA) content and the expression level of plasma membrane intrinsic protein (PIP) gene were significantly increased in the hydrated root under partial root-zone irrigation compared with those under normal irrigation. The results suggested that the increased JA content, as a signal molecule, up-regulated the expression level of PIP gene in dehydrated root and increased water uptake capacity of roots and guaranteed water balance of leaves, and then contributed to a relatively high Pn. Partial root-zone irrigation combined with relatively high plant density (225000 plants·hm-2) is an important agronomic alternative for water saving in cotton plantation in the dry land areas.


Assuntos
Irrigação Agrícola/métodos , Gossypium/crescimento & desenvolvimento , Água , Biomassa , China , Fotossíntese
2.
Ecotoxicol Environ Saf ; 182: 109451, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31352213

RESUMO

Potassium (K) is an essential macronutrient for plant growth and development. However, in China, available K is relatively low in the soil, and with the extensive use of chemical fertilizer, K use efficiency is constantly reducing, and consequently increasing the potential risk of environmental pollution and economic loss. Therefore, it is essential to reduce the negative impact of over-fertilization on the environment to obtain optimal crop yield. Biochar as a soil amendment has been applied to improve soil fertility and increase crop yield. However, the effects of successive biochar application on cotton yield, agronomy efficiencies and potash fertilizer reduction are not well documented. Our results of a pot experiment showed that the application of 1% biochar to soil under different K levels significantly improved dry mass accumulation and K content of different plant parts, and increased the number of buds, bolls and effective branches of cotton. Particularly, plants treated with 150 mg/kg K2O and 1% biochar had the highest growth parameters. The most important characteristics including the harvest index, K fertilizer contribution index, partial factor productivity, agronomic efficiency and apparent recovery efficiency of K under C1 (1% biochar) were generally greater than those under C0 (without biochar). The 75 mg/kg K2O application was optimal to produce the highest yield with 1% biochar, demonstrating that biochar can increase cotton yield and therefore, reduces chemical K fertilizer application and alleviates agricultural environment risks of chemical fertilizer.


Assuntos
Carvão Vegetal/química , Produção Agrícola/métodos , Fertilizantes/análise , Gossypium/crescimento & desenvolvimento , Potássio/análise , Solo/química , China , Minerais
3.
BMC Plant Biol ; 19(1): 312, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31307379

RESUMO

BACKGROUND: The WOX (WUSCHEL-RELATED HOMEOBOX) gene family encodes a class of transcription factors that are unique to green plants, where they are involved in regulating the development of plant tissues and organs by determining cell fate. Although the importance of the WOX gene is well known, there are few studies describing their functions in cotton. RESULTS: In this study, 32 WOX genes were found in Gossypium hirsutum. Phylogenetic analysis showed that WOX proteins of cotton can be divided into three clades: the ancient, intermediate, and WUS clades. The number of WOX proteins in the WUS clade was greater than the sum of the proteins in the other two clades. Our analysis revealed that 20 GhWOX genes are distributed on 16 cotton chromosomes and that duplication events are likely to have contributed to the expansion of the GhWOX family. All GhWOX genes have introns, and each GhWOX protein contains multiple motifs. RNA-seq data and real-time PCR showed that GhWOX13 gene subfamily is specifically expressed at a high level in cotton fibers. We also identified putative GA, NAA, and BR response elements in the promoter regions of the GhWOX13 genes and GhWOX13 transcripts were significantly induced by GA, NAA, and BR. CONCLUSIONS: Our data provides a useful resource for future studies on the functional roles of cotton WOX genes and shows that the GhWOX13 genes may influence cotton fiber development. Our results also provide an approach for identifying and characterizing WOX protein genes in other species.


Assuntos
Fibra de Algodão , Genes de Plantas , Gossypium/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Gossypium/crescimento & desenvolvimento , Proteínas de Homeodomínio/genética , Filogenia , Reguladores de Crescimento de Planta/fisiologia , Proteínas de Plantas/genética
4.
BMC Plant Biol ; 19(1): 220, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138186

RESUMO

BACKGROUND: Brassinosteroids (BRs) play crucial roles in drought tolerance, but the underlying molecular mechanisms remain unclear in the important oilseed and fiber crop, cotton (Gossypium hirsutum L.). RESULTS: To elucidate how BRs mediate drought tolerance in cotton, a cotton brassinosteroid (BR)-deficient mutant, pag1 (pagoda1), was employed for analysis. Importantly, the pag1 mutant showed increased sensitivity to drought stress, with shorter primary roots and fewer lateral roots. The number of stomata was significantly increased in the mutant, and the stomata aperture was much wider than that of the control plants. These mutant plants therefore showed an increased water loss rate. Furthermore, the abscisic acid (ABA) content, photosynthetic efficiency and starch content of the mutant were significantly lower than those of the wild type. The overall performance of the mutant plants was worse than that of the wild-type control under both normal and drought conditions. Moreover, Proteomic analysis revealed reduced levels of stress-related proteins in pag1 plants. CONCLUSIONS: These results suggest that BRs may modulate the drought tolerance of cotton by regulating much genes that related to drought stress and multiple organ responses to drought, including root growth, stomata development, the stomata aperture and photosynthesis. This study provides an important basis for understanding drought resistance regulated by BRs and cultivating drought-resistant cotton lines.


Assuntos
Brassinosteroides/metabolismo , Secas , Gossypium/fisiologia , Gossypium/genética , Gossypium/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteômica
5.
BMC Genomics ; 20(1): 421, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138116

RESUMO

BACKGROUND: Cotton is the most essential textile crop worldwide, and phytohormones are critical for cotton fiber development. One example is the role of auxin in fiber initiation, but we know little molecular basis. MicroRNAs (miRNAs) have a significant function in cotton development; nevertheless their role in fiber initiation remains unclear. Here, exogenous IAA was applied to cotton plant before anthesis. Utilizing small RNA sequencing, the mechanism underlying miRNA-mediated regulation of fiber initiation under exogenous IAA treatment was investigated. RESULTS: With exogenous IAA application, the endogenous IAA and GA contents of IAA treated (IT) ovules were higher than control (CK) ovules at the fiber initiation stage, while endogenous ABA content was lower in IT than CK. Using scanning electron microscopy, we found the fiber number and size were significantly promoted in IT at 0 DPA. Fiber quality analysis showed that fiber length, uniformity, strength, elongation, and micronaire of IT were higher than CK, though not statistically significant, while lint percent was significantly higher in IT. We generated six small RNA libraries using - 3, 0, and 3 DPA ovules of IT and CK, and identified 58 known miRNAs and 83 novel miRNAs together with the target genes. The differential expressed miRNAs number between IT and CK at - 3, 0, 3 DPA was 34, 16 and 24, respectively. Gene ontology and KEGG pathway enrichment analyses for the target genes of the miRNAs expressed in a differential manner showed that they were significantly enriched in 30 terms and 8 pathways. QRT-PCR for those identified miRNAs and the target genes related to phytohormones and fiber development was performed, and results suggested a potential role of these miRNAs in fiber initiation. CONCLUSIONS: The exogenous IAA application affected the relative phytohormone contents in ovule and promoted fiber initiation in cotton. Identification and profiling of miRNAs and their targets at the fiber initiation stage provided insights for miRNAs' regulation function of fiber initiation. These findings not only shed light on the regulatory network of fiber growth but also offer clues for cotton fiber amelioration strategies in cotton.


Assuntos
Gossypium/genética , Ácidos Indolacéticos/farmacologia , MicroRNAs/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Perfilação da Expressão Gênica , Genes de Plantas , Gossypium/efeitos dos fármacos , Gossypium/crescimento & desenvolvimento , Gossypium/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Óvulo Vegetal/efeitos dos fármacos , Óvulo Vegetal/genética , Óvulo Vegetal/crescimento & desenvolvimento , Óvulo Vegetal/ultraestrutura , Reguladores de Crescimento de Planta/metabolismo , Análise de Sequência de RNA
6.
Plant Biol (Stuttg) ; 21(5): 911-919, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31077623

RESUMO

The dormancy of seeds of upland cotton can be broken during dry after-ripening, but the mechanism of its dormancy release remains unclear. Freshly harvested cotton seeds were subjected to after-ripening for 180 days. Cotton seeds from different days of after-ripening (DAR) were sampled for dynamic physiological determination and germination tests. The intact seeds and isolated embryos were germinated to assess effects of the seed coat on embryo germination. Content of H2 O2 and phytohormones and activities of antioxidant enzymes and glucose-6-phosphate dehydrogenase were measured during after-ripening and germination. Germination of intact seeds increased from 7% upon harvest to 96% at 30 DAR, while embryo germination improved from an initial rate of 82% to 100% after 14 DAR. Based on T50 (time when 50% of seeds germinate) and germination index, the intact seed and isolated embryo needed 30 and 21 DAR, respectively, to acquire relatively stable germination. The content of H2 O2 increased during after-ripening and continued to increase within the first few hours of imbibition, along with a decrease in abscisic acid (ABA) content. A noticeable increase was observed in gibberellic acid content during germination when ABA content decreased to a lower level. Coat removal treatment accelerated embryo absorption of water, which further improved the accumulation of H2 O2 and changed peroxidase content during germination. For cotton seed, the alleviation of coat-imposed dormancy required 30 days of after-ripening, accompanied by rapid dormancy release (within 21 DAR) in naked embryos. H2 O2 acted as a core link between the response to environmental changes and induction of other physiological changes for breaking seed dormancy.


Assuntos
Germinação , Gossypium/fisiologia , Dormência de Plantas , Sementes/fisiologia , Antioxidantes/metabolismo , Germinação/fisiologia , Glucosefosfato Desidrogenase/metabolismo , Gossypium/crescimento & desenvolvimento , Peróxido de Hidrogênio/metabolismo , Dormência de Plantas/fisiologia
7.
BMC Genomics ; 20(1): 402, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31117950

RESUMO

BACKGROUND: Cotton (Gossypium spp.) is the most important natural fiber crop worldwide, and cottonseed oil is its most important byproduct. Phospholipid: diacylglycerol acyltransferase (PDAT) is important in TAG biosynthesis, as it catalyzes the transfer of a fatty acyl moiety from the sn-2 position of a phospholipid to the sn-3 position of sn-1, 2-diacylglyerol to form triacylglycerol (TAG) and a lysophospholipid. However, little is known about the genes encoding PDATs involved in cottonseed oil biosynthesis. RESULTS: A comprehensive genome-wide analysis of G. hirsutum, G. barbadense, G. arboreum, and G. raimondii herein identified 12, 11, 6 and 6 PDATs, respectively. These genes were divided into 3 subfamilies, and a PDAT-like subfamily was identified in comparison with dicotyledonous Arabidopsis. All GhPDATs contained one or two LCAT domains at the C-terminus, while most GhPDATs contained a preserved single transmembrane region at the N-terminus. A chromosomal distribution analysis showed that the 12 GhPDAT genes in G. hirsutum were distributed in 10 chromosomes. However, none of the GhPDATs was co-localized with quantitative trait loci (QTL) for cottonseed oil content, suggesting that their sequence variations are not genetically associated with the natural variation in cottonseed oil content. Most GhPDATs were expressed during the cottonseed oil accumulation stage. Ectopic expression of GhPDAT1d increased Arabidopsis seed oil content. CONCLUSIONS: Our comprehensive genome-wide analysis of the cotton PDAT gene family provides a foundation for further studies into the use of PDAT genes to increase cottonseed oil content through biotechnology.


Assuntos
Diacilglicerol O-Aciltransferase/genética , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Família Multigênica , Fosfolipídeos/análise , Óleos Vegetais/análise , Proteínas de Plantas/genética , Diacilglicerol O-Aciltransferase/metabolismo , Evolução Molecular , Gossypium/crescimento & desenvolvimento , Gossypium/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Sementes/química
8.
Ying Yong Sheng Tai Xue Bao ; 30(4): 1218-1226, 2019 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-30994282

RESUMO

A long-term field experiment was conducted to investigate the effects of continuous cotton production years (0 as control, 5, 10, 15 and 20 years) and straw return on soil organic carbon (SOC) structure and stability by using Fourier transform infrared spectroscopy (FTIR) in Manas River valley of Xinjiang. The results showed that the relative peak intensity of polysaccharide and aromatics decreased with increasing continuous cropping years, whereas the aliphatic and alcoholic phenols relative peak intensity and the CH/C=C increased. The content of soil particulate organic carbon (POC) increased significantly in the 5-yr of cotton production farmland and then decreased with the increases of continuous cropping years. POC content was 5.11 times higher in 5-yr than that of the control. The content of mineral-bound organic carbon (MOC) was the highest in 10-yr farmland, being 1.84 times higher than that of the control. The highest value of the ratio of POC and MOC content (ω(POC)/ω(MOC)) was observed in 5-yr farmland. Together, long-term continuous cotton production with straw return led to SOC structure aliphatic and soil mineral binding increased the protection of organic matter, thus increasing the stability of soil organic matter.


Assuntos
Agricultura/métodos , Carbono , Fertilizantes , Gossypium/crescimento & desenvolvimento , Minerais , Solo , Espectroscopia de Infravermelho com Transformada de Fourier
9.
BMC Plant Biol ; 19(1): 138, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975072

RESUMO

BACKGROUND: Gossypium hirsutum L. is grown worldwide and is the largest source of natural fiber crop. We focus on exploring the favorable alleles (FAs) for upland cotton varieties improvement, and further understanding the history of accessions selection and acumination of favorable allele during breeding. RESULTS: The genetic basis of phenotypic variation has been studied. But the accumulation of favorable alleles in cotton breeding history in unknown, and potential favorable alleles to enhance key agronomic traits in the future cotton varieties have not yet been identified. Therefore, 419 upland cotton accessions were screened, representing a diversity of phenotypic variations of 7362 G. hirsutum, and 15 major traits were investigated in 6 environments. These accessions were categorized into 3 periods (early, medium, and modern) according to breeding history. All accessions were divided into two major groups using 299 polymorphic microsatellite markers: G1 (high fiber yield and quality, late maturity) and G2 (low fiber yield and quality, early maturity). The proportion of G1 genotype gradually increased from early to modern breeding periods. Furthermore, 21 markers (71 alleles) were significantly associated (-log P > 4) with 15 agronomic traits in multiple environments. Seventeen alleles were identified as FAs; these alleles accumulated more in the modern period than in other periods, consistent with their phenotypic variation trends in breeding history. Our results demonstrate that the favorable alleles accumulated through breeding effects, especially for common favorable alleles. However, the potential elite accessions could be rapidly screened by rare favorable alleles. CONCLUSION: In our study, genetic variation and genome-wide associations for 419 upland cotton accessions were analyzed. Two favorable allele types were identified during three breeding periods, providing important information for yield/quality improvement of upland cotton germplasm.


Assuntos
Alelos , Variação Genética , Gossypium/genética , Agricultura , Estudo de Associação Genômica Ampla , Genótipo , Gossypium/crescimento & desenvolvimento , Fenótipo , Melhoramento Vegetal
10.
Mol Genet Genomics ; 294(3): 789-810, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30887144

RESUMO

Upland cotton (Gossypium hirsutum L.) race stocks may possess desirable traits for the genetic improvement of cotton. Quantitative trait locus (QTL) analysis can assist in uncovering new alleles from unadapted race stocks. In this study, three sets of chromosome segment introgression lines (ILs) were developed from three backcrosses (BC3) between three race stocks, G. hirsutum races latifolium accs. TX-34 and TX-48 and punctatum acc. TX-114, as donor parents and Texas Marker-1 (TM-1) as the recurrent parent. Based on a total of 452 polymorphic simple sequence repeat (SSR) markers in BC3F2 genotyping, 149, 150 and 184 ILs were obtained from TM-1 × TX-34, TM-1 × TX-48 and TM-1 × TX-114, respectively. The average introgressed chromosomal segment length was 12.7 cM, and the total genetic distance was 3268 cM covering approximately 73.4% of the Upland cotton genome. The BC3F2, BC3F2:3 and BC3F2:4 progeny, which produced the ILs, were evaluated for yield and fibre quality traits. A total of 128 QTLs were detected, each of which explained 1.6-13.0% of the phenotypic variation. Thirty-five common QTLs related to eight traits were detected. Six QTL clusters were found on five chromosomes. Thirty-eight QTLs were previously unreported, and they may be footprints of cotton domestication. Domestication or artificial selection by humans successfully eliminated most unfavourable QTLs (21/38); however, some favourable QTLs (17/38) are not present in modern cultivars, demonstrating the importance of race stocks for improving cotton cultivars. The 26 elite ILs developed could be used to improve the yield and fibre quality components simultaneously. These results provide information on desirable QTLs for cotton improvement.


Assuntos
Fibra de Algodão/normas , Genes de Plantas/genética , Gossypium/genética , Locos de Características Quantitativas/genética , Biomassa , Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Cruzamentos Genéticos , Domesticação , Genoma de Planta/genética , Gossypium/classificação , Gossypium/crescimento & desenvolvimento , Melhoramento Vegetal/métodos , Seleção Genética
11.
Environ Sci Pollut Res Int ; 26(14): 14259-14265, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30864027

RESUMO

Cotton crops generate millions of tons of lignocellulosic waste in Brazil that could be used in energy generation; however, the main destination of this raw material is soil incorporation. The aim of this work was to perform an energetic characterization and evaluation of briquettes produced from different agricultural waste of naturally colored cotton for power generation. The cultivars Brasil Sementes (BRS) Jade and Topazio were studied, with white cotton (BRS 286) as standard for comparison purposes. Two different parts of each species, stalk and cotton shell, were analyzed by bulk density, proximate analysis, higher heating value, cellulose, hemicellulose, protein, fat and lignin content, thermogravimetric analysis, and briquette mechanical strength. The results of the energetic characterization indicated a higher energetic potential of the colored species when compared with the white cotton, especially because of the volatile matter content, fixed carbon, and higher heating value. The briquette mechanical strength was higher in the samples formulated by a mixture of stalk and shell. Finally, it was concluded that the waste from colored cotton cultivars, Jade and Topazio, is capable to generate briquettes with good mechanical and physico-chemical characteristics, especially those formed by the mixture of stalk and shell.


Assuntos
Fontes Geradoras de Energia , Gossypium/química , Resíduos/análise , Biomassa , Brasil , Celulose/análise , Gossypium/crescimento & desenvolvimento , Calefação , Lignina/análise , Proteínas de Plantas/análise
12.
J Basic Microbiol ; 59(6): 632-644, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30900762

RESUMO

Microbial biofilms are gaining importance in agriculture, due to their multifaceted agronomic benefits and resilience to environmental fluctuations. This study focuses on comparing the influence of single inoculation-Azotobacter chroococcum (Az) or Trichoderma viride (Tv) and their biofilm (Tv-Az), on soil and plant metabolic activities in wheat and cotton grown under Phytotron conditions. Tv-Az proved superior to all the other treatments in terms of better colonisation, plant growth attributes and 10-40% enhanced availability of macronutrients and micronutrients in the soil, over control. Confocal and scanning electron microscopy showed that the cells attached to the root tips initially, followed by their proliferation along the surface of the roots. Soil polysaccharides, proteins and dehydrogenase activity showed several fold enhancement in Tv-Az biofilm inoculated samples. Time course studies revealed that the population of Az and Tv in the rhizoplane and rhizosphere was significantly higher with a 0.14-0.31 log colony-forming unit (CFU) increase in the biofilm-inoculated treatment in both crops. Enhancement in soil biological activities was facilitated by the improved colonisation of the biofilm, due to the synergistic association between Tv and Az. This demonstrates the utility of Tv-Az biofilm as a multifunctional plant growth promoting and soil fertility enhancing option in agriculture.


Assuntos
Azotobacter/fisiologia , Biofilmes/crescimento & desenvolvimento , Gossypium/crescimento & desenvolvimento , Nutrientes/análise , Solo/química , Trichoderma/fisiologia , Triticum/crescimento & desenvolvimento , Inoculantes Agrícolas/crescimento & desenvolvimento , Inoculantes Agrícolas/fisiologia , Disponibilidade Biológica , Gossypium/microbiologia , Nutrientes/farmacocinética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Rizosfera , Microbiologia do Solo , Triticum/microbiologia
13.
Gene ; 709: 36-47, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30898717

RESUMO

Cotton fiber initiation is the first step in fiber development, and it determines the yield. Here, genome-wide transcriptome profiling of Gossypium arboreum was performed to determine the molecular basis of cotton fiber initiation. A comparison of the transcriptomes of fiber-bearing ovules at -0.5, 0, 0.5, 1, 1.5, 2, 2.5 and 3 d post-anthesis detected 12,049 differentially expressed genes that mainly participated in ribosome, carbon metabolism and amino acid biosynthesis pathways. Genes encoding alcohol dehydrogenase 1 and hydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyl transferase, involving in fatty acid degradation and flavonoid biosynthesis, were enriched. Furthermore, 1049 differentially expressed transcription factors were identified. Among these, 17 were trihelix family transcription factors, which play important roles in plant development and responses to biotic and abiotic stresses. In total, 52 full-length trihelix genes, named as GaGTs, were identified in G. arboreum and located in 12 of the 13 cotton chromosomes. Transcriptomic data and a quantitative real-time PCR analysis indicated that several GaGTs were significantly induced during fiber initiation in G. arboreum. Thus, the genome-wide comprehensive analysis of gene expression in G. arboreum fiber initiation will serve as a useful resource for unraveling the functions of specific genes. The phylogenetic relationships and expression analyses of the G. arboreum trihelix genes established a solid foundation for future comprehensive functional analyses of the GaGTs.


Assuntos
Fibra de Algodão , Gossypium/crescimento & desenvolvimento , Gossypium/genética , Sequências Hélice-Alça-Hélice , Fatores de Transcrição/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Genoma de Planta , Estudo de Associação Genômica Ampla , Sequências Hélice-Alça-Hélice/genética , Família Multigênica , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Fatores de Transcrição/química
14.
J Insect Sci ; 19(1)2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30753608

RESUMO

Thermal environments of the arid western United States are often harsh compared with the ranges of temperatures favorable for development and survival of crop insect pests. In cotton [Gossypium spp. (Malvales: Malvaceae)], new irrigation practices such as deficit irrigation may impact populations of pest and beneficial arthropods by temporarily altering temperature profiles within the plant canopy. Most information regarding the temperature-dependent development and survival of an important cotton pest, the western tarnished plant bug (Lygus hesperus Knight), is derived from constant temperature studies. We examined the development and survival of L. hesperus nymphs under constant (±0.2°C) and variable (±8°C) temperature regimes at daily mean temperatures of 15, 22, and 29°C. Under the low temperature (15°C), stadium lengths and duration of the nymphal stage were shorter when temperatures were variable compared with a constant temperature. No differences in development times were observed between regimes at the medium temperature (22°C). Except for the first stadium, development times under the high variable temperature regime were longer compared with the high constant regime (29°C). Nymph survival was unaffected by temperature regime except at the lowest temperature, where daily thermal fluctuations substantially improved survival compared with the constant conditions. These results suggest that temporarily increased crop canopy temperatures caused by altered irrigation schemes are unlikely to substantially reduce the growth of L. hesperus populations. However, enhanced nymphal development and survival under low variable temperatures likely contribute to the survival of overwintering L. hesperus in the absence of acute, low-temperature mortality.


Assuntos
Temperatura Baixa , Heterópteros/crescimento & desenvolvimento , Temperatura Alta , Animais , Gossypium/crescimento & desenvolvimento , Longevidade , Ninfa/crescimento & desenvolvimento
15.
J Insect Sci ; 19(1)2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30794727

RESUMO

Stink bugs (Hemiptera: Pentatomidae) are economic pests in fruit, vegetable, grain, and row crops worldwide. Pyramid traps baited with lures of stink bug aggregation pheromones capture these pests in the field, but stink bugs can congregate on plants near traps. Our specific objective was to examine the area of arrestment of stink bugs based on their density on cotton at different distances from pheromone-baited traps. We used lures of the aggregation pheromone of Euschistus spp., methyl (2E,4Z)-2,4-decadienoate (MDD), and Plautia stali Scott, methyl [2E,4E,6Z]-2,4,6-decatrienoate (MDT). Overall, Euschistus servus (Say), Euschistus tristigmus (Say), Chinavia hilaris (Say), and Nezara viridula (L.) were the main stink bug species on cotton. Over the 3-yr study, adult stink bug density was significantly higher on the row of cotton immediately adjacent to a pheromone-baited trap than on the second and third row from the trap. Stink bug density was significantly lower on the seventh cotton row beyond the trap in 2015, on the fourth, eighth, and 16th rows in 2017, and on the fourth and eighth rows in 2018 compared to the two or three rows nearest the trap. These results indicate that adult stink bugs congregated mainly on the three cotton rows (2.73 m in width) nearest a trap. Management strategies utilizing pheromone-baited traps for stink bug control, such as trap cropping in combination with traps, should take into consideration this area of arrestment.


Assuntos
Quimiotaxia , Decanoatos/farmacologia , Heterópteros/fisiologia , Feromônios/farmacologia , Animais , Gossypium/crescimento & desenvolvimento , Controle de Insetos , Densidade Demográfica
16.
PLoS One ; 14(2): e0205083, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30811435

RESUMO

This paper demonstrates the application of aerial multispectral images in cotton plant phenotyping. Four phenotypic traits (plant height, canopy cover, vegetation index, and flower) were measured from multispectral images captured by a multispectral camera on an unmanned aerial system. Data were collected on eight different days from two fields. Ortho-mosaic and digital elevation models (DEM) were constructed from the raw images using the structure from motion (SfM) algorithm. A data processing pipeline was developed to calculate plant height using the ortho-mosaic and DEM. Six ground calibration targets (GCTs) were used to correct the error of the calculated plant height caused by the georeferencing error of the DEM. Plant heights were measured manually to validate the heights predicted from the imaging method. The error in estimation of the maximum height of each plot ranged from -40.4 to 13.5 cm among six datasets, all of which showed strong linear relationships with the manual measurement (R2 > 0.89). Plot canopy was separated from the soil based on the DEM and normalized differential vegetation index (NDVI). Canopy cover and mean canopy NDVI were calculated to show canopy growth over time and the correlation between the two indices was investigated. The spectral responses of the ground, leaves, cotton flower, and ground shade were analyzed and detection of cotton flowers was satisfactory using a support vector machine (SVM). This study demonstrated the potential of using aerial multispectral images for high throughput phenotyping of important cotton phenotypic traits in the field.


Assuntos
Aeronaves , Produção Agrícola , Gossypium , Tecnologia de Sensoriamento Remoto , Análise Espectral , Produção Agrícola/métodos , Flores , Mapeamento Geográfico , Gossypium/anatomia & histologia , Gossypium/crescimento & desenvolvimento , Fenótipo , Folhas de Planta , Distribuição Aleatória , Tecnologia de Sensoriamento Remoto/instrumentação , Tecnologia de Sensoriamento Remoto/métodos , Análise Espectral/métodos , Máquina de Vetores de Suporte
17.
Mol Genet Genomics ; 294(2): 469-478, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30604069

RESUMO

Anthocyanins are a class of pigments ubiquitously distributed in plants and play roles in adoption to several stresses. The red plant gene (R1) promotes light-induced anthocyanin accumulation and red/purple pigmentation in cotton. Using 11 markers developed via genome resequencing, the R1 gene was located in an interval of approximately 136 kb containing three annotated genes. Among them, a PAP1 homolog, GhPAP1D (Gohir.D07G082100) displayed differential transcript level in the red- and green-plant leaves. GhPAP1D encoded a R2R3-MYB transcription factor and its over-expression resulted in increased anthocyanin accumulation in transgenic tobaccos and cottons. Dual luciferase assay indicated that GhPAP1D activated the promoters of several cotton anthocyanin structural genes in tobacco leaves. Importantly, we found that the GhPAP1D-overexpressing cotton leaves had increased resistance to both bollworm and spite mite. Our data demonstrated that GhPAP1D was the controlling gene of the red plant phenotype in cotton, and as the major anthocyanin regulator, this gene was potential to create transgenic cottons with resistance to a broad spectrum of herbivores.


Assuntos
Antocianinas/genética , Resistência à Doença/genética , Gossypium/genética , Folhas de Planta/genética , Animais , Antocianinas/metabolismo , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Gossypium/crescimento & desenvolvimento , Helmintos/genética , Controle Biológico de Vetores , Pigmentação/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/parasitologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/parasitologia , Regiões Promotoras Genéticas , Tetranychidae/genética , Tetranychidae/patogenicidade
18.
Environ Sci Pollut Res Int ; 26(5): 4987-4996, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30604361

RESUMO

Honeybee (Apis mellifera L.) provides not only bee products of immense value but also render invaluable free service as cross-pollination and propagation of several cultivated and wild species, thereby, maintaining biological diversity. Bee larvae and adults might be killed or suffer various sublethal effects when placed in contact with pollen and nectar contaminated with insecticides. The present work was conducted to investigate the toxicity of seven insecticides on laboratory using oral toxicity test and their side effects on A. mellifera in cotton fields. Results indicated that lambda-cyhalothrin was the most toxic-tested pesticide, recording the lowest LC50 and LC90 values at all tested periods and the lowest LT50 and LT90 at all tested concentrations, followed by abamectin, spinosad, chlorpyrifos, and emamectin benzoate. On the other side, dipel and pyridalyl recording the highest LC50 and LC90 at all tested periods and the highest LT50 and LT90 at all tested concentrations. As for the application of pesticides in cotton fields, the tested pesticides significantly increased the number of dead workers in comparison with control. The tested pesticides significantly decreased bee foraging activities, i.e., number of foraging workers, number of worker collecting nectar, number of worker gathering pollen grains, area of broad workers, and honey bee yields. Dipel and pyridalyl were the most safety pesticides on honey bee workers in laboratory and field, so it could be introduced as a component in IPM programs of cotton pests.


Assuntos
Abelhas/efeitos dos fármacos , Inseticidas/toxicidade , Polinização/efeitos dos fármacos , Animais , Abelhas/crescimento & desenvolvimento , Comportamento Animal/efeitos dos fármacos , Gossypium/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Pólen/química , Análise de Sobrevida , Testes de Toxicidade
19.
Int J Mol Sci ; 20(2)2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30654456

RESUMO

Cyclophilins (CYPs) are a member of the immunophilin superfamily (in addition to FKBPs and parvulins) and play a significant role in peptidyl-prolyl cis-trans isomerase (PPIase) activity. Previous studies have shown that CYPs have important functions in plants, but no genome-wide analysis of the cotton CYP gene family has been reported, and the specific biological function of this gene is still elusive. Based on the release of the cotton genome sequence, we identified 75, 78, 40 and 38 CYP gene sequences from G. barbadense, G. hirsutum, G. arboreum, and G. raimondii, respectively; 221 CYP genes were unequally located on chromosomes. Phylogenetic analysis showed that 231 CYP genes clustered into three major groups and eight subgroups. Collinearity analysis showed that segmental duplications played a significant role in the expansion of CYP members in cotton. There were light-responsiveness, abiotic-stress and hormone-response elements upstream of most of the CYPs. In addition, the motif composition analysis revealed that 49 cyclophilin proteins had extra domains, including TPR (tetratricopeptide repeat), coiled coil, U-box, RRM (RNA recognition motif), WD40 (RNA recognition motif) and zinc finger domains, along with the cyclophilin-like domain (CLD). The expression patterns based on qRT-PCR showed that six CYP expression levels showed greater differences between Xinhai21 (long fibres, G. barbadense) and Ashmon (short fibres, G. barbadense) at 10 and 20 days postanthesis (DPA). These results signified that CYP genes are involved in the elongation stage of cotton fibre development. This study provides a valuable resource for further investigations of CYP gene functions and molecular mechanisms in cotton.


Assuntos
Fibra de Algodão , Ciclofilinas/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Gossypium/crescimento & desenvolvimento , Gossypium/genética , Família Multigênica , Proteínas de Plantas/genética , Cromossomos de Plantas/genética , Genes de Plantas , Filogenia , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Especificidade da Espécie
20.
Fungal Biol ; 123(1): 42-50, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30654956

RESUMO

The large-scale long-term plantation of cotton in the Xinjiang region has been accompanied by a regular and wide outbreak of soil-borne fungal diseases such as verticillium wilt, which significantly damaged the local cotton industry. High-throughput sequencing data showed that the cotton field cultivation management measures pose a significant influence upon the original ecological soil fungal community structure. During long-term continuous cropping of cotton, a new soil fungal community structure emerges after several repeated adjustments over five years. The number of verticillium wilt pathogens in the soil increased rapidly with prolonged continuous cropping time, reaching a maximum at around the 10th y; moreover, the abundance of the verticillium wilt pathogen only serves as one of numerous essential factors for disease occurrence. The fungal community structure and the abundance of verticillium wilt pathogens in local cotton fields are gradually formed under joint effects of year-long continuous cropping and supporting cultivation management measures.


Assuntos
Agricultura/métodos , Gossypium/crescimento & desenvolvimento , Micobioma , Rizosfera , Microbiologia do Solo , Doenças das Plantas/microbiologia , Verticillium/isolamento & purificação
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