基因工程改良棉花纤维品质研究进展

棉花作为世界上重要的经济作物,其纤维品质是衡量棉花品质的重要指标.优良的纤维品质是国内外棉花育种的主要目标之一,面临常规育种改良品质的瓶颈,通过转基因技术改良棉花纤维品质是棉花遗传育种致力研究的重要领域.介绍棉纤维发育相关分子机理研究、棉纤维品质改良功能基因的发掘以及利用基因工程技术改良棉花纤维品质的最新进展,并对今后的研究进行展望.     

棉纤维特异基因及其特异启动子的研究进展

棉花是重要经济作物。由于单纯利用常规育种手段很难同步提高棉花产量和品质,利用基因工程与常规育种方法相结合来改良棉花纤维品质是当前品质育种中一个切实可行的方法。本文总结了棉花纤维发育的过程,并对近几年国内外棉纤维发育相关基因及其特异启动子的研究现状进行了综述,以期为利用基因工程手段改良棉花品质提供参考。     

陆地棉纤维优势表达基因GhRACK1的克隆与序列分析

纤维品质改良是我国棉花育种的主要目标之一,纤维特异或优势表达基因的挖掘是利用基因工程手段改良纤维品质的关键。根据苏棉12纤维中优势表达的GhRACK1 EST序列设计引物,通过RACE技术克隆了GhRACK1基因的全长cDNA。推导的氨基酸序列含有4个串联的WD基序,属于WD40重复家族,与已知的RACK1蛋白同源性达70％以上,PDB模拟的蛋白三维结构也与已知的RACK1蛋白结构相似。荧光定量PCR分析表明GhRACK1在纤维中的表达量比叶片中高20倍以上。研究结果为棉花纤维品质改良基因工程提供了新的基因资源。     

转FBP7::iaaM基因陆地棉种质冀资139纤维品质性状杂种优势分析

提高棉花(Gossypium hirsutum)产量兼顾改良纤维品质是棉花育种的重要目标,而优良种质创新是品种改良的基础。FBP7::iaaM基因能够调控棉花胚珠表皮细胞IAA的含量,进而促进棉纤维发育的起始。利用含有FBP7::iaaM基因的种质IF1-1,通过常规杂交育种手段实现了目的基因向骨干亲本的转移,培育了优...     

四川省棉花品种现状分析

对1985～1996年四川省棉花品种区域试验资料的分析结果表明：在近10年间四川选育的棉花品种单产水平有较大提高,但纤维品质的改良进展较缓慢,分析其原因,主要是亲本间亲缘关系较近,亲本组配以品种间杂交为主,对海岛棉、亚洲棉及其衍生材料等未能充分利用。要选育优质、高产、抗逆性强的棉花品种,应加强对棉花资源材料的研究,拓宽育种亲本的利用范围,利用现代生物技术与常规育种技术有机结合,加快品质育种进程,培育出具有突破性的品种是当务之急。     

棉花转基因技术和转基因棉花

概述了棉花转基因育种技术和转基因抗虫棉、转抗除草剂基因棉花、转抗病基因棉花、转品质改良基因棉花及天然彩色棉花等的研究概况。     

转基因棉花研发及商业化发展态势

正国内外转基因棉花的研发主要集中于抗虫、抗除草剂、抗病、耐盐碱、抗旱和纤维改良等性状研究,但只有转基因抗虫、抗除草剂和纤维改良等性状得到注册应用。转基因棉花的大规模商业化种植,可以有效控制棉花害虫与杂草并改善棉花纤维品质,显著提高棉花产量,降低生产成本。主要描述了棉花转基因的主要技术和规模化转基因技术体系平台,论述了转基因棉花近年来的总体研发状况及在棉花抗虫、抗除草剂及纤维改良方面的研究进展,分析了全球前四大转基因棉花种植国家(印度、美国、中国和巴基斯坦)转基因棉花的商业化发展态势,并归纳总结了转基因棉花的安全性问题及今后主要的发展方向。     

植物细胞壁沟槽结构与生物质利用研究展望

细胞壁是植物细胞的重要组成部分,是生物质的主要成分,不仅对植物形态学起中心调控作用,还对植物机械强度、纤维品质和生物质综合利用起决定性作用.本文将简要介绍植物细胞壁结构与功能研究进展,重点分析细胞壁关键结构因子,原创性提出植物细胞壁纳米级沟槽结构模型与生物质酶解分子机理,并探讨遗传改良植物细胞壁结构的新方法与新途径,旨在从本质上极大提高生物质综合利用效率,改良棉花纤维品质和增强作物抗逆能力.     

棉花高品质纤维性状的主基因与多基因遗传分析

利用主基因与多基因混合遗传模型联合分析方法 ,通过纤维强度不同的 5个亲本配制的 8个组合 ,研究了棉花主要纤维品质性状的遗传。联合分析发现 ,在不同性状不同组配方式的 14个组合中 ,有 12个存在主基因 ,表明了纤维性状主基因存在的普遍性 ,以F2∶3 家系的预测效果最好 ;双亲纤维品质性状均存在较大差异的组合——— 72 35×TM1F2 代强度主基因的遗传率为 0 .196 ,麦克隆值为 0 .32 0 ,长度为 0 .139,回交世代的主基因遗传率小。除纤维长度总的显性效应为较高的正值外 ,其余各纤维性状的主基因显性与多基因显性的总和为负值或接近 0 ,杂合状态下大多数纤维品质性状表型值会偏向中亲值或低亲值 ,单纯依靠表型选择效率低。因此 ,很有必要对棉花品质性状进行分子标记辅助育种选择     

国产二代转基因棉研究获突破

据近日举行的"第2代转基因棉花纤维品质研究进展"新闻发布会,中国第2代转基因棉花研究总体跃居世界领先水平,并拥有国际发明专利等自主知识产权,为摆脱高端棉花长期依赖进口的局面打下了坚实基础。由中国农业科学院棉花研究所选育的"中棉所70",利用海岛棉优质渐渗系与转基因抗虫棉品系杂交、分子聚合技术培育而成,纤维长32.5 mm,达到优质棉标准。由中国农业科学     

Inheritance of long staple fiber quality traits of Gossypium barbadense in G. hirsutum background using CSILs

Gossypium hirsutum is a high yield cotton species that exhibits only moderate performance in fiber qualities. A promising but challenging approach to improving its phenotypes is interspecific introgression, the transfer of valuable traits or genes from the germplasm of another species such as G. barbadense, an important cultivated extra long staple cotton species. One set of chromosome segment introgression lines (CSILs) was developed, where TM-1, the genetic standard in G. hirsutum, was used as the recipient parent and the long staple cotton G. barbadense Hai7124 was used as the donor parent by molecular marker-assisted selection (MAS) in BC₅S_1–4 and BC₄S_1–3 generations. After four rounds of MAS, the CSIL population was comprised of 174 lines containing 298 introgressed segments, of which 86 (49.4%) lines had single introgressed segments. The total introgressed segment length covered 2,948.7 cM with an average length of 16.7 cM and represented 83.3% of tetraploid cotton genome. The CSILs were highly varied in major fiber qualities. By integrated analysis of data collected in four environments, a total of 43 additive quantitative trait loci (QTL) and six epistatic QTL associated with fiber qualities were detected by QTL IciMapping 3.0 and multi-QTL joint analysis. Six stable QTL were detected in various environments. The CSILs developed and the analyses presented here will enhance the understanding of the genetics of fiber qualities in long staple G. barbadense and facilitate further molecular breeding to improve fiber quality in Upland cotton.     

QTL mapping in A-genome diploid Asiatic cotton and their congruence analysis with AD-genome tetraploid cotton in genus Gossypium

Asiatic cotton(Gossypium arboreum L.) is an Old World cultivated cotton species.The sinense race was planted extensively in China.Due to the advances in spinning technology during the last century,the species was replaced by the New World allotetraploid cotton G.hirsutum L.Gossypium arboreum is still grown in India and Pakistan and also used as an elite in current cotton breeding programs.In addition,G.arboreum serves as a model for genomic research in Gossypium.In the present study,we generated an A-genome diploid cotton intraspecific genetic map including 264 SSR loci with three morphological markers mapped to 1 3 linkage groups.The map spans 2,508.71 cM with an average distance of 9.4 cM between adjacent loci.A population containing 1 76 F2:3 families was used to perform quantitative trait loci(QTL)mapping for 17 phenotypes using Multiple QTL Model(MQM)of MapQTL ver 5.0.Overall,108 QTLs were detected on 13 chromosomes.Thirty-one QTLs for yield and its components were detected in the F2 population.Forty-one QTLs for yield and its components were detected in the F2:3 families with a total of 43 QTLs for fiber qualities.Two QTLs for seed cotton weight/plant and lint index and three QTLs for seed index were consistently detected both in F2 and F2:3.Most QTLs for fiber qualities and yields were located at the same interval or neighboring intervals.These results indicated that the negative correlation between fiber qualities and yield traits may result from either pleiotropic effect of one gene or linkage effects of multiple closely linked genes.     

Variations and Transmission of QTL Alleles for Yield and Fiber Qualities in Upland Cotton Cultivars Developed in China

Cotton is the world’s leading cash crop, and genetic improvement of fiber yield and quality is the primary objective of cotton breeding program. In this study, we used various approaches to identify QTLs related to fiber yield and quality. Firstly, we constructed a four-way cross (4WC) mapping population with four base core cultivars, Stoneville 2B, Foster 6, Deltapine 15 and Zhongmiansuo No.7 (CRI 7), as parents in Chinese cotton breeding history and identified 83 QTLs for 11 agronomic and fiber quality traits. Secondly, association mapping of agronomical and fiber quality traits was based on 121 simple sequence repeat (SSR) markers using a general linear model (GLM). For this, 81 Gossypium hirsutum L. accessions including the four core parents and their derived cultivars were grown in seven diverse environments. Using these approaches, we successfully identified 180 QTLs significantly associated with agronomic and fiber quality traits. Among them were 66 QTLs that were identified via linkage disequilibrium (LD) and 4WC family-based linkage (FBL) mapping and by previously published family-based linkage (FBL) mapping in modern Chinese cotton cultivars. Twenty eight and 44 consistent QTLs were identified by 4WC and LD mapping, and by FBL and LD mapping methods, respectively. Furthermore, transmission and variation of QTL-alleles mapped by LD association in the three breeding periods revealed that some could be detected in almost all Chinese cotton cultivars, suggesting their stable transmission and some identified only in the four base cultivars and not in the modern cultivars, suggesting they were missed in conventional breeding. These results will be useful to conduct genomics-assisted breeding effectively using these existing and novel QTL alleles to improve yield and fiber qualities in cotton.     

SSR marker-assisted improvement of fiber qualities in Gossypium hirsutum using G. barbadense introgression lines

Key message

This study demonstrates the first practical use of CSILs for the transfer of fiber quality QTLs into Upland cotton cultivars using SSR markers without detrimentally affecting desirable agronomic characteristics.

Abstract

Gossypium hirsutum is characterized by its high lint production and medium fiber quality compared to extra-long staple cotton G. barbadense. Transferring valuable traits or genes from G. barbadense into G. hirsutum is a promising but challenging approach through a traditional interspecific introgression strategy. We developed one set of chromosome segment introgression lines (CSILs), where TM-1, the genetic standard in G. hirsutum, was used as the recipient parent and the long staple cotton G. barbadense cv. Hai7124 was used as the donor parent by molecular marker-assisted selection (MAS). Among them, four CSILs, IL040-A4-1, IL080-D6-1, IL088-A7-3 and IL019-A2-6, found to be associated with superior fiber qualities including fiber length, strength and fineness QTL in Xinjiang were selected and backcrossed, and transferred these QTLs into three commercial Upland cotton cultivars such as Xinluzao (XLZ) 26, 41 and 42 grown in Xinjiang. By backcrossing and self-pollinating twice, five improved lines (3262-4, 3389-2, 3326-3, 3380-4 and 3426-5) were developed by MAS of background and introgressed segments. In diverse field trials, these QTLs consistently and significantly offered additive effects on the target phenotype. Furthermore, we also pyramided two segments from different CSILs (IL080-D6-1 and IL019-A2-6) into cultivar 0768 to accelerate breeding process purposefully with MAS. The improved lines pyramided by these two introgressed segments showed significant additive epistatic effects in four separate field trials. No significant alteration in yield components was observed in these modified lines. In summary, we first report that these CSILs have great potential to improve fiber qualities in Upland cotton MAS breeding programs.     

Recent progression and future perspectives in cotton genomic breeding

Upland cotton is an important global cash crop for its long seed fibers and high edible oil and protein content.Progress in cotton genomics promotes the advancement of cotton genetics,evolutionary studies,functional genetics,and breeding,and has ushered cotton research and breeding into a new era.Here,we summarize high-impact genomics studies for cotton from the last 10 years.The diploid Gossypium arboreum and allotetraploid Gossypium hirsutum are the main focus of most genetic and genomic studi...     

赤霉素信号转导与棉纤维的分子发育

赤霉素(Gas)作为一种高效能的植物生长调节物质对棉纤维的分化和发育有着非常重要的影响, 但是, 一直以来有关赤霉素与棉纤维分化和发育的分子机制的研究还很少。文章论述了近年来GA信号组分、转导途径的分子生物学研究进展以及GA与棉纤维分子发育的相关研究成果, 旨在为揭示赤霉素调控棉纤维分化和发育的分子机制以及改善棉纤维品质的棉花育种工作提供新的思路。     

Molecular diversity, genomic constitution, and QTL mapping of fiber quality by mapped SSRs in introgression lines derived from Gossypium hirsutum?×?G. darwinii Watt

Because the genetic basis of current upland cotton cultivars is narrow, exploring new germplasm resources and discovering novel alleles relevant to important agronomic traits have become two of the most important themes in the field of cotton research. In this study, G. darwinii Watt, a wild cotton species, was crossed with four upland cotton cultivars with desirable traits. A total of 105 introgression lines (ILs) were successfully obtained. By using 310 mapped SSRs evenly distributed across the interspecific linkage map of G. hirsutum?×?G. barbadense, these 105 ILs and their corresponding parents were analyzed. A total of 278 polymorphic loci were detected among the 105 ILs, and the average length of introgression segments accumulated to 333.5?cM, accounting for 6.7?% of the whole genome. These lines included many variations. However, high similarity coefficients existed between lines, even between those derived from different parents. Finally, all the ILs and their upland cotton parents were used for association mapping of fiber quality in three environments. A total of 40 SSRs were found to be associated with five fiber quality indexes (P?相似文献