Chemical defoliation is essential for mechanized harvesting of cotton (Gossypium hirsutum L.), yet the molecular mechanisms governing abscission zone (AZ) cell fate and cell-wall remodeling remain unresolved. Here, single-nucleus RNA sequencing (snRNA-seq) coupled with Monocle2 trajectory analysis delineates a pseudotemporal transition of protective-layer cells from C16_0 to C16_1, which coincides with AZ maturation. We identify the cell-wall glycoprotein GhSKS6 as a central hub in this differentiation process. CRISPR/Cas9-mediated knockout of GhSKS6 impairs AZ fracture-layer formation, delays leaf abscission, and downregulates genes associated with hemicellulose and xyloglucan remodeling. Subcellular localization and plasmolysis assays confirm the residency of GhSKS6 in the cell wall, while its overexpression in protoplasts accelerates cell wall regeneration. Moreover, the NAC transcription factor GhNAC47 directly binds to the GhSKS6 promoter to activate its expression, thereby modulating cotton leaf abscission. Our findings reveal a regulatory module involving GhNAC47 and GhSKS6 that coordinates protective-layer formation and cell-wall remodeling, offering precise molecular targets for breeding machine-harvested cotton cultivars.
Brassica napus yellow-seeded genotypes have higher seed oil content and quality than black-seeded types, but the mechanisms controlling seed coat color (SCC) remain unclear, partly due to limited gap-free references. We generated the telomere-to-telomere genome assembly of the black-seeded cultivar Zhongyou 821 using PacBio HiFi, ultralong ONT, and Hi-C sequencing. Using this reference, genome-wide association study (GWAS) of 504 accessions identified BnaWRKY44 as a major SCC candidate gene. CRISPR-Cas9 knockout of BnaWRKY44 lightened SCC, increased oil content and unsaturated fatty acids, and improved oil quality. Haplotype analysis defined the elite BnaWRKY44Hap4 allele and enabled development of a diagnostic CAPS marker for breeding. Transcriptomic, Y1H and dual-LUC assays showed that BnaWRKY44 directly binds and regulates the BnaVPT1 promoter. BnaVPT1 knockout confirmed its roles in SCC lightening and flavonoid biosynthesis. This work provides a T2T rapeseed resource and a BnaWRKY44-BnaVPT1 module for breeding high-oil, yellow-seeded rapeseed.
Arsenic (As) contamination poses a significant threat to crop production and food safety. In plants, arsenate [As(V)] is taken up into cells through phosphate transporters due to their chemical similarity, where it disrupts metabolic processes and causes oxidative stress. However, the precise role of phosphate transporters in As accumulation and tolerance remains unclear. Here, we investigated the function of BnPHT5;1b, a vacuolar phosphate influx transporter in Brassica napus. Double mutants of two BnPHT5;1b genes, BnA09.PHT5;1b and BnCn.PHT5;1b (hereafter referred to as BnPHT5;1b DM) exhibited enhanced tolerance to As(V) at the seedling stage, showing increased biomass, longer roots, and higher chlorophyll content under As stress. Transcriptome analysis revealed that both wild-type and mutant plants activated oxidative stress responses, but the BnPHT5;1b DM displayed stronger enrichment of antioxidant and detoxification pathways. Importantly, disruption of BnPHT5;1bs promoted root-to-shoot As translocation, with xylem sap As(III) and As(V) increased by 51.0% and 75.0%, respectively, and As concentrations in cotyledons, old leaves, and new leaves increased by 61.3%, 153.7%, and 129.7%, respectively. This was accompanied by 6.8-fold higher As accumulation in shoot cell walls, while seed As levels remained similar to or slightly lower than those of wild-type. These findings establish BnPHT5;1b as a key regulator of As transport and detoxification in B. napus. This study reveals a previously unrecognized strategy for enhancing arsenate tolerance while promoting root-to-shoot As translocation and shoot cell wall retention without increasing seed As accumulation, providing a potential genetic resource for phytoremediation of As-contaminated soils.
Phosphorus (P) is an essential macronutrient for the growth and yield of crops. However, there is limited understanding of the regulatory mechanisms of phosphate (Pi) homeostasis, and its impact on growth, development, and yield-related traits in Brassica napus. Here, we identified four NITROGEN LIMITATION ADAPTATION1 (BnaNLA1) genes in B. napus; their expression was predominant in roots and suppressed by Pi starvation-induced BnamiR827. All the BnaNLA1 proteins have similar sequences, subcellular localizations, and abilities to rescue the growth defects of the atnla1 mutant. One of the genes, BnaA09.NLA1, is expressed abundantly in roots, and also in old leaves, anthers, and pollen. Knocking out BnaNLA1 genes or overexpressing BnamiR827 resulted in increased concentrations of Pi in leaves and stamens and reduced pollen viability, thereby negatively impacting seed yield. Bimolecular fluorescence complementation (BiFC) and split-ubiquitin yeast two-hybrid (Y2H) analyses demonstrated that BnaA09.NLA1 interacted with seven Pi transporters highly expressed in roots and/or anthers (i.e. BnaPT8/10/11/27/35/37/42) to regulate Pi uptake and Pi allocation in anthers. Taken together, this study demonstrates that the BnamiR827-BnaA09.NLA1-BnaPHT1 module is involved in the regulation of Pi uptake and Pi allocation in floral organs, which is vital for the growth, pollen viability, and seed yield of B. napus.
With the objective of investigating the basis of phosphorus (P) utilization efficiency (PUE), physiological and morphological traits, two P-efficient and two P-inefficient rapeseed (Brassica napus L.) cultivars were compared at the seedling stage. P-efficient cultivars showed root morphological adaptation, high P uptake activity, and greater phospholipid degradation under low P stress. Improving root morphological adaptation and reducing lipid-P allocation could allow increasing PUE in rapeseed seedlings.
Chemical defoliation stands as the ultimate tool in enabling the mechanical harvest of cotton, offering economic and environmental advantages. However, the underlying molecular mechanism that triggers leaf abscission through defoliant remains unsolved. In this study, we meticulously constructed a transcriptomic atlas through single-nucleus mRNA sequencing (snRNA-seq) of the abscission zone (AZ) from cotton petiole. We identified two newly-formed cell types, abscission cells and protection layer cells in cotton petiole AZ after defoliant treatment. GhRLF1 (RAPID LEAF FALLING 1), as one of the members of the cytokinin oxidase/dehydrogenase (CKX) gene family, was further characterized as a key marker gene unique to the abscission cells following defoliant treatment. Overexpression of GhRLF1 resulted in reduced cytokinin accumulation and accelerated leaf abscission. Conversely, CRISPR/Cas9-mediated loss of GhRLF1 function appeared to delay this process. Its interacting regulators, GhWRKY70, acting as "Pioneer" activator, and GhMYB108, acting as "Successor" activator, orchestrate a sequential modulation of GhWRKY70/GhMYB108-GhRLF1-CTK (cytokinin) within the AZ to regulate cotton leaf abscission. GhRLF1 not only regulates leaf abscission but also reduces cotton yield. Consequently, transgenic lines that exhibit rapid leaf falling and require less defoliant but show unaffected cotton yield were developed for mechanical harvesting. This was achieved using a defoliant-induced petiole-specific promoter, proPER21, to drive GhRLF1 (proPER21::RLF1). This pioneering biotechnology offers a new strategy for the chemical defoliation of machine-harvested cotton, ensuring stable production and reducing leaf debris in harvested cotton, thereby enhancing environmental sustainability.
BACKGROUND:Cotton is a major world cash crop and an important source of natural fiber, oil, and protein. Drought stress is becoming a restrictive factor affecting cotton production. To facilitate the development of drought-tolerant cotton varieties, it is necessary to study the molecular mechanism of drought stress response by exploring key drought-resistant genes and related regulatory factors.RESULTS:In this study, two cotton varieties, ZY007 (drought-sensitive) and ZY168 (drought-tolerant), showing obvious phenotypic differences under drought stress, were selected. A total of 25,898 drought-induced genes were identified, exhibiting significant enrichment in pathways related to plant stress responses. Under drought induction, At subgenome expression bias was observed at the whole-genome level, which may be due to stronger inhibition of Dt subgenome expression. A gene co-expression module that was significantly associated with drought resistance was identified. About 90% of topologically associating domain (TAD) boundaries were stable, and 6613 TAD variation events were identified between the two varieties under drought. We identified 92 genes in ZY007 and 98 in ZY168 related to chromatin 3D structural variation and induced by drought stress. These genes are closely linked to the cotton response to drought stress through canonical hormone-responsive pathways, modulation of kinase and phosphatase activities, facilitation of calcium ion transport, and other related molecular mechanisms.CONCLUSIONS:These results lay a foundation for elucidating the molecular mechanism of the cotton drought response and provide important regulatory locus and gene resources for the future molecular breeding of drought-resistant cotton varieties.
Global water scarcity and extreme weather intensify drought stress, significantly reducing cotton yield and quality worldwide. Drought treatments are conducted using a population of chromosome segment substitution lines generated from E22 (G. hirsutum) and 3-79 (G. barbadense) as parental lines either show superior yields or fiber quality under both control and drought conditions. Fourteen datasets, covering 4 yields and 4 quality traits, are compiled and assessed for drought resistance using the drought resistance coefficient (DRC) and membership function value of drought resistance (MFVD). Genome-wide association studies, linkage analysis, and bulked segregant analysis are combined to analyze the DR-related QTL. A total of 121 significant QTL are identified by DRC and MFVD of the 8 traits. CRISPR/Cas9 and virus-induced gene silencing techniques verified DRR1 and DRT1 as pivotal genes in regulating drought resistant of cotton, with hap3-79 exhibiting greater drought resistance than hapE22 concerning DRR1 and DRT1. Moreover, 14 markers with superior yield and fiber quality are selected for drought treatment. This study offers valuable insights into yield and fiber quality variations between G. hirsutum and G. barbadense amid drought, providing crucial theoretical and technological backing for developing cotton varieties resilient to drought, with high yield and superior fiber quality.
Vacuolar Pi transporters (VPTs) have recently been identified as important regulators of cellular Pi status in Arabidopsis thaliana and Oryza sativa. In the oil crop Brassica napus, BnA09PHT5;1a and BnC09PHT5;1a are two homologs of AtPHT5;1, the vacuolar Pi influx transporter in Arabidopsis. Here, we show that Pi deficiency induces the transcription of both homologs of PHT5;1a genes in B. napus leaves. Brassica PHT5;1a double mutants (DM) had smaller shoots and higher cellular Pi concentrations than wild-type (WT, Westar 10), suggesting the potential role of BnPHT5;1a in modulating cellular Pi status in B. napus. A proteomic analysis was performed to estimate the role of BnPHT5;1a in Pi fluctuation. Results show that Pi deprivation disturbs the abundance of proteins in the physiological processes involved in carbohydrate metabolism, response to stimulus and stress in B. napus, while disruption of BnPHT5;1a genes may exacerbate these processes. Besides, the processes of cell redox homeostasis, lipid metabolic and proton transmembrane transport are supposed to be unbalanced in BnPHT5;1a DM under the -Pi condition. Noteworthy, disruption of BnPHT5;1a genes severely alters the abundance of proteins related to ATP biosynthesis, and proton/inorganic cation transmembrane under normal Pi condition, which might contribute to B. napus growth limitations. Additionally, seven new protein markers of Pi homeostasis are identified in B. napus. Taken together, this study characterizes the important regulatory role of BnPHT5;1a genes as vacuolar Pi influx transporters in Pi homeostasis in B. napus.
Edible oils with high unsaturated fatty acids, particularly oleic acid, are beneficial to human health. Cotton is one of the top five oil crops in the world, but the mechanism of high-quality oil synthesis and regulatory networks in cotton are largely unclear. Here, we identified Leafy cotyledon1-like 1 (GhL1L1), a NF-YB subfamily gene that is specifically expressed during somatic embryogenesis and seed maturation in cotton. Overexpression of GhL1L1 regulates the contents of unsaturated fatty acids in cotton, especially in the seeds, which is associated with altered expression of the cotton fatty acid biosynthesis-related genes. GhL1L1 synergistically enhanced the expression of GhFAD2-1A by binding to the G-box in its promoter, leading to an increase in the content of linoleic acid. Furthermore, this activation could be enhanced by GhNF-YC2 and GhNF-YA1 by form a transcriptional complex. Collectively, these results contribute to provide new insights into the molecular mechanism of oil biosynthesis in cotton and can facilitate genetic manipulation of cotton varieties with enhanced oil content.
Phosphorus (P) is an indispensable macronutrient serving a variety of functions in plants. Inositol pyrophosphates (PP-InsPs) nutrient messengers play vital roles in the signaling of P status and plant growth and development. In this review, we summarize (1) the biosynthetic pathway of PP-InsPs and their regulation by plant P status, (2) the effects of PP-InsPs on the function of the SPX domain-containing proteins in signaling plant P status, (3) the effects of inositol pyrophosphates on auxin signaling through TIR1 and on jasmonate signaling through COI1, and (4) the potential crosstalk between P status signaling and phytohormone signaling in plants mediated by inositol pyrophosphates. It is concluded that the interactions between inositol pyrophosphates and their binding proteins are central to plant P status and developmental responses to different P supply.
[目的]研究不同甘蓝型油菜品种对土壤磷分布异质性的响应规律及其差异,为减磷增效提供理论依据.[方法]以中双 11 号(ZS11)和圣光 168(SG168)两个甘蓝型油菜品种为试验材料,于 2019-2020 年在湖北武汉开展根箱分根试验(供试土壤速效磷含量为 2.75 mg/kg),在湖北武穴两个速效磷含量不同的田块(高磷肥力和低磷肥力田块土壤速效磷含量分别为 17.63 和 8.65 mg/kg)开展磷肥条施试验.试验设置不施磷(0P/0P)、局部供磷(1P/0P)和均匀供磷(1P/1P)3 个处理,于成熟期测定株高、分枝数、角果数、千粒重、产量、干物质积累、籽粒磷积累量和磷肥偏生产力等性状.[结果]不施磷(0P/0P)处理,SG168的株高、分枝数、角果数、产量、各部位干物质积累量和籽粒磷积累量均高于ZS11.相同供磷处理,根箱试验和田间试验SG168 的株高、分枝数、产量和磷肥偏生产力均高于ZS11.与 1P/1P处理相比,1P/0P处理两个甘蓝型油菜品种的磷肥偏生产力均提高,并且高磷田块的提升幅度大于低磷田块.田间试验低磷田块中,与 1P/1P处理相比,1P/0P处理两个油菜品种产量均显著降低;田间试验高磷田块,与 1P/1P处理相比,1P/0P处理ZS11 产量显著降低,而SG168 的产量无显著差异.[结论]局部供磷可以增强甘蓝型油菜对土壤中磷的吸收利用,提高地力贡献率和磷肥偏生产力.SG168 的高产稳产和低磷适应能力强于ZS11.在土壤磷肥力水平高的田块,通过局部施磷的方式种植SG168可以实现不减产的同时减少一半磷肥的施用.
Abiotic stress seriously affects the growth, yield, and fiber quality of cotton. It is of great importance to cultivate drought-resistant and salt-tolerant cotton. NAC (NAM, ATAF1/2, and CUC2) is a plant-specific transcription factor, which is widely involved in the response to abiotic stress. Here, we discovered the GhNAC3 gene isolated from the expression profile of drought stress in cotton and verified its functions in cotton. First, GhNAC3 was strongly induced expression by drought and salt stresses. Gene structure analysis revealed that GhNAC3 had a conserved NAC domain and was homologous to several stress-related NAC transcription factors gene of Arabidopsis. Subcellular localization and transcriptional activation assays revealed that GhNAC3 was a nuclear protein with a C-terminal transcriptional activation domain. Overexpression of GhNAC3 enhanced Arabidopsis tolerance to drought stress with reduced sensitivity to ABA, characterized by increased germination and cotyledon rates under drought stress, and promoted root elongation. VIGS silencing of GhNAC3 reduced cotton tolerance to drought stress as indicated by the low water content of the leaves under drought treatment, significantly faster water loss and lower ABA content in detached leaves, along with the accumulation of more hydrogen peroxide (H2O2) and malondialdehyde (MDA). In conclusion, GhNAC3 plays an important role in the abiotic stress of cotton, which might have great application potential in molecular breeding of cotton varieties with drought resistance.
植物细胞的全能性是指每个细胞均具有该植物的全部遗传信息,其离体组织或细胞在适当培养条件下具有发育成完整植株的潜能.植物体细胞胚胎发生是最能体现植物细胞全能性的一种方式,其在人工种子、单倍体育种、无性繁殖和种质保存等领域具有广阔的应用前景,其发生的机制也是基础研究领域的热点.近年来,随着技术的进步及研究的深入,植物体细胞胚胎发生的分子调控机制取得了重要进展.植物体细胞胚胎发生是一系列基因在时空顺序上表达调控的结果.本文系统综述了体细胞胚胎发生过程中激素及逆境胁迫信号转导、胚胎发育相关转录因子、胞外蛋白和表观遗传调控的作用,并对本领域未来的研究重点及方向进行了展望.
Soil salinity is a major constraint for reducing crop productivity worldwide. To combat this situation, the current project was aimed to examine the effect of plant growth-promoting rhizobacteria (PGPR) inoculation on the growth of cotton (Gossypium hirsutum, var. Jin668) plants during salt stress and to identify salt stress-responsive genes in cotton plants. For this purpose, two bacteria, Bacillus subtilis and Bacillus pumilus were selected among the 20 strains isolated from the cotton rhizosphere under the salt stress (200 mM NaCl) and identified by 16 S rRNA sequencing. B. subtilis and B. pumilus were applied to Jin668 plants under salt stress which enhanced resistance to salt stress (leaf and root growth) compared to only salt-treated plants and control plants. Transcriptomic analysis revealed 556 differentially expressed genes (481 up-regulated and 75 down-regulated) in the B. subtilis + Salt versus Salt treatments and 943 (536 up-regulated and 407 down-regulated) genes in the B. pumilus + Salt versus Salt treatments. KEGG analysis of B. pumilus + Salt versus Salt and B. pumilus + Salt versus Salt revealed the pathways plant-pathogen interaction and plant hormone signal transduction were expressed in both treatments, while ascorbate and aldarate metabolism pathways and glyoxylate and dicarboxylate metabolism pathways were uniquely expressed in the B. pumilus + Salt versus Salt comparison, and the pentose and glucuronate interconversions pathway was uniquely expressed in the B. pumilus + Salt treatment versus Salt comparison. These data showed that B. subtilis and B. pumilus significantly enhance salt stress tolerance in cotton plants during salt stress conditions.
INTRODUCTION:Drought is the principal abiotic stress that severely impacts cotton (Gossypium hirsutum) growth and productivity. Upon sensing drought, plants activate stress-related signal transduction pathways, including ABA signal and mitogen-activated protein kinase (MAPK) cascade. However, as the key components with the fewest members in the MAPK cascade, the function and regulation of GhMKKs need to be elucidated. In addition, the relationship between MAPK module and the ABA core signaling pathway remains incompletely understood. OBJECTIVE:Here we aim to elucidate the molecular mechanism of cotton response to drought, with a focus on mitogen-activated protein kinase (MAPK) cascades activating ABA signaling. METHODS:Biochemical, molecular and genetic analysis were used to study the GhMAP3K62-GhMKK16-GhMPK32-GhEDT1 pathway genes. RESULTS:A nucleus- and membrane-localized MAPK cascade pathway GhMAP3K62-GhMKK16-GhMPK32, which targets and phosphorylates the nuclear-localized transcription factor GhEDT1, to activate downstream GhNCED3 to mediate ABA-induced stomatal closure and drought response was characterized in cotton. Overexpression of GhMKK16 promotes ABA accumulation, and enhances drought tolerance via regulating stomatal closure under drought stress. Conversely, RNAi-mediated knockdown of GhMKK16 expression inhibits ABA accumulation, and reduces drought tolerance. Virus-induced gene silencing (VIGS)-mediated knockdown of either GhMAP3K62, GhMPK32 or GhEDT1 expression represses ABA accumulation and reduces drought tolerance through inhibiting stomatal closure. Expression knockdown of GhMPK32 or GhEDT1 in GhMKK16-overexpressing cotton reinstates ABA content and stomatal opening-dependent drought sensitivity to wild type levels. GhEDT1 could bind to the HD boxes in the promoter of GhNCED3 to activate its expression, resulting in ABA accumulation. We propose that the MAPK cascade GhMAP3K62-GhMKK16-GhMPK32 pathway functions on drought response through ABA-dependent stomatal movement in cotton.
Root is the main organ of plants that absorbs water and nutrients. The growth of the root system will directly affect the absorption and utilization of nutrients, the resistance to abiotic stress and finally the yield of cotton. In this study, a natural population of 220 upland cotton accessions and a chromosomal segment substitution line (CSSL) population with 325 lines, derived from the crossing and backcrossing of Gossypium barbadense acc. 3-79 with G. hirsutum cv. ‘Emian 22’ were selected to collect the major root phenotypic traits. Four major traits, namely main root length (MRL), root fresh weight (RFW), root dry weight (RDW) and lateral root angle (LRA) were investigated, and genome-wide association analysis (GWAS) was performed for four root traits in natural populations in combination with genome resequencing. The results showed that the four root traits of the natural population are all in line with normal distribution, and the CSSL population were all in skewed distribution. The mean value of root index of CSSL population was higher than that of natural population. A total of 2,714,140 SNP was obtained from the resequencing data of the natural population. The principal component analysis (PCA) showed that the RFW and MRL could be used as two indexes for cotton root classification, through which the cotton root could be divided into nine types in each population. The analysis of population structure demonstrated that the natural population can be divided into five subgroups. Genome-wide association analysis rrevealed that two association sites were simultaneously associated by RFW and RDW in natural populations. The results of this study provide a theoretical basis for further research on root system architecture (RSA) and its genetic mechanism, and it is also of great significance to cotton breeding of abiotic stress resistance.
Recent progress has shown that vacuolar Pi transporters (VPTs) are important for cellular Pi homoeostasis in Arabidopsis thaliana and Oryza sativa under fluctuating external Pi supply, but the identity and involvement of VPTs in cellular Pi homoeostasis in Brassica napus is poorly understood. Here, we identified two vacuolar Pi influx transporters B. napus, BnA09PHT5;1b and BnCnPHT5;1b, and uncovered their necessity for cellular Pi homoeostasis through functional analysis. Both Brassica proteins are homologs of Arabidopsis AtPHT5;1 with a similar sequence, structure, tonoplast localization, and VPT activity. Brassica pht5;1b double mutants had smaller shoots and larger shoot cellular Pi concentrations than wild-type B. napus, which contrasts with a previous study of the Arabidopsis pht5;1 mutant, suggesting that PHT5;1-VPTs play different roles in cellular Pi homoeostasis in seedlings of B. napus and A. thaliana. Disruption of BnPHT5;1b genes also caused Pi toxicity in floral organs, reduced seed yield and impacted seed traits, consistent with the proposed role of AtPHT5;1 in floral Pi homoeostasis in Arabidopsis. Taken together, our studies identified two vacuolar Pi influx transporters in B. napus and revealed the distinct and conserved roles of BnPHT5;1bs in cellular Pi homoeostasis in this plant species.
In order to understand the molecular mechanism of cotton's response to drought during the flowering and boll stage, transcriptomics and metabolomics were carried out for two introgression lines (drought-tolerant line: T307; drought-sensitive line: S48) which were screened from Gossypium hirsutum cv. ‘Emian22’ with some gene fragments imported from Gossypium barbadense acc. 3–79, under drought stress by withdrawing water at flowering and boll stage. Results showed that the basic drought response in cotton included a series of broad-spectrum responses, such as amino acid synthesis, hormone (abscisic acid, ABA) signal transduction, and mitogen-activated protein kinases signal transduction pathway, which activated in both drought-tolerant and drought-sensitive lines. However, the difference of their imported fragments and diminished sequences triggers endoplasmic reticulum (ER) protein processing, photosynthetic-related pathways (in leaves), and membrane solute transport (in roots) in drought-tolerant line T307, while these are missed or not activated in drought-sensitive line S48, reflecting the different drought tolerance of the two genotypes. Virus-induced gene silencing assay of drought-tolerant differentially expressed heat shock protein (HSP) genes (mainly in leaf) and ATP-binding cassette (ABC) transporter genes (mainly in roots) indicated that those genes play important role in cotton drought tolerant. Combined analysis of transcriptomics and metabolomics highlighted the important roles of ER-stress-related HSP genes and root-specific ABC transporter genes in plants drought tolerance. These results provide new insights into the molecular mechanisms underlying the drought stress adaptation in cotton.
植物根际微生物群落对植物生长和适逆性至关重要,本研究对干旱条件下棉花根际真菌群落进行分析,旨在探明干旱胁迫对棉花根际真菌多样性和群落结构的影响,为利用有益微生物提高棉花水分利用率提供理论依据。以陆地棉Jin 668 (Gossypium hirsutum cv. Jin668)为试验材料,采用盆栽控水方式,对处于开花期的棉花根际土壤(SDP)和未种植棉花土壤(SOPD)进行干旱处理,正常浇水的棉花根际土壤(SPN)和无棉花土壤(SNPN)为对照。从中采集土壤样品,提取DNA,采用IlluminaMiseq对真菌ITS1区域进行高通量测序,研究土壤中真菌多样性。结果共鉴定到970个OTUs,SNPN、SOPD、SPN和SDP样品中真菌OTUs数量分别为481、528、743和752个,其中288个OTUs为所有组共有。对获得OTUs进行门、纲、目、科和属5个分类水平的划分表明,棉花根际真菌群落结构主要由子囊菌门(82.70%)和担子菌门(10.15%)组成;干旱处理使粪壳菌纲(Sordariomycetes)、粪壳菌目(Sordariales)和毛壳菌科(Chaetomiaceae)丰度显著降低,而散囊菌目(Eurotiales)、发菌科(Trichocomaceae)、曲霉属(Aspergillus)和青霉属(Penicillum)的丰度显著增加。多样性分析结果显示,与未种棉花的土壤相比,有棉花的土壤中真菌群落的α多样性显著增加;同时, SPN和SDP之间的真菌群落结构更相似,而与SNPN和SOPD间差异较大。研究表明,棉花根际存在丰富的真菌群落,干旱对土壤中真菌的丰度和多样性有显著影响。本研究从微生物的角度为提高棉花耐旱性的研究提供新见解。