棉花床土调制剂对棉花苗田土壤肥力的影响

为了探明不同配方的棉花床土调制剂对棉花苗田土壤肥力的影响,于2005年4月在湖南农业大学实验基地对2004年筛选的4个新配方进行棉花育苗试验。研究结果表明,处理1、2较处理3、4棉花苗床肥力提高,杀菌剂和生长调节剂对土壤成分的肥力没有影响。因此,处理1、2对棉苗生长有促进作用。     

雷蒙德氏棉DNase Ⅰ高敏感位点(DHSs)文库构建方法

染色质DNA对DNase Ⅰ表现出高敏感性的位点(DNase Ⅰ hypersensitive sites,DHSs)多是顺式作用元件所在的位置,包括启动子、增强子、调节子和衰减子等.研究DHSs位点的数目及其动态变化是探明顺式作用元件功能、揭示基因表达调控机制,乃至进行基因编辑和创新遗传材料的重要辅助手段.本文借鉴水稻和拟南芥DHSs文库构建方法,通过优化设计,初步建立了二倍体雷蒙德氏棉(Gossypium raimondii D5)的DHSs文库,为深入进行棉花功能基因组研究奠定基础.     

陆地棉基因转移技术研究初报

应用农杆菌菌株Ａｔ４４０４携带抗卡那霉素基因（氨基葡萄糖磷酸转移酶）、Ｇｕｓ基因（葡萄糖苷酸酶）以及Ｂ．Ｔ毒蛋白基因，对陆地棉４个不同栽培品种鲁棉６号、鲁棉１０２４、中棉１２、中棉１９的无菌苗下胚轴和茎尖分生组织区作基因导入的研究，获得转基因的棉花试管苗．在以胚轴作为转化体系的培养过程中，只有鲁棉６号经过了愈伤组织发生、胚状体形成及植株再生途径．若以３～５ｄ的无菌苗芽顶端分生组织作为转化体系，经转化的茎尖分生组织培养在无激素或低浓度激素的ＭＳ培养基上，则可较容易地从多个品种中获得转基因的再生植株．以此方法进行基因转移，时间短、方法简便、不受品种来源及基因型的限制．这一技术将有利于提高棉花转基因植株的成活率     

陆地棉LTR反转录转座子的数量分布与功能分析

LTR(Long terminal repeat)反转录转座子是真核生物基因组中普遍存在的一类遗传因子,它们以RNA为媒介在基因组中不断自我复制.在高等植物中,LTR反转录转座子是基因组的重要成分之一.本研究通过多种方法挖掘并注释了陆地棉基因组中的LTR反转录转座子,结果表明陆地棉基因组LTR反转录转座子的Gypsy超家族与基因的分布呈近似的反比关系,而Copia超家族在各染色体的起始端有较多的分布.通过皮尔森相关系数发现陆地棉LTR反转录转座子的拷贝数与染色体大小之间有强相关性.在LTR反转录转座子上游和下游分布的基因具有类似的富集特征,其分子功能主要集中在结合和催化活性等方面.本研究结果加深了对陆地棉LTR反转录转座子的认识,为深入研究棉花基因组提供了重要数据支撑.     

Rapid plant regeneration from cotton (Gossypium hirsutum L.)

A simple and rapid regeneration method of cotton (Gossypium hirsutum L. cv. Xinluzao 4) is described. The proper use of phytohormone KT and IBA validly promoted the survival rate of test-tube plants and shortened the period of culture in combination with the techniques of micro-propagation and graft.     

棉花花粉发育过程中同工酶的研究

本文利用超薄胶电泳技术对陆地棉（ＧｏｓｓｙｐｉｕｍＨｉｒｓｕｔｕｍＬ．）花粉发育各期的酯酶的过氧化物酶的同工酶活性变化进行了研究，结果发现，在花粉第一次有丝分裂结束之前，存在大量的低分子量酯酶和过氧化物酶，花粉成熟后又新出现了一些大分子量酯酶的过氧化物酶，提示：花粉的发育过程是一个基因差异表达的过程，并受一定的机制控制．     

Characterization, development and exploitation of EST-derived microsatellites in Gossypium raimondii Ulbrich

COTTON IS AN IMPORTANT GLOBAL CASH CROP. IN THE RECENTYEARS, MOLECULAR MARKER TECHNOLOGY HAS BEEN WIDELY APPLIED TO SUCH STUDIES ON COTTON AS GENETIC MAP- PING[1―4], VARIETY PURITY DETECTION[5], GENETIC DIVERSITY ANALYSIS[6], MOLECULAR MARKER-ASSISTED BR…     

Evaluation of the introgressed lines and screening for elite germplasm in Gossypium

THERE ARE 51 SPECIES IN THE GENUS OF GOSSYPIUM[1]. EXCEPT UPLAND COTTON CULTIVARS, WILD CULTIVARS, SPECIES AND RACE HAVE ABUNDANT GENETIC POLYMORPHISMS DUE TO THEIR VARIOUS ENVIRONMENTAL DISTRIBUTION AND LONG-TERM NATURAL SELECTION. THEREFORE, THEY POSSESS LOTS OF EXCEL- LENT GENES THAT CAN BE USED TO EXPLOIT POTENTIAL TRAITS, SUCH AS DROUGHT RESISTANCE, DISEASE AND INSECT …     

棉花GhGAI1基因克隆及其功能的初步分析

DELLA蛋白是赤霉素信号通路中重要的蛋白质作用因子,负调节植物体中赤霉素的水平,同时受到生长素、脱落酸和乙烯的共同调节。根据已知的生物信息数据,本研究克隆了棉花GhGAl1基因,序列分析表明它编码DELLA蛋白。构建GFP与GhGAl1融合蛋白重组质粒,利用根癌农杆菌介导的花浸泡转基因方法转化拟南芥columbia生态型植株,进行过量表达实验。结果表明,GFP—GhGAl1融合蛋白定位于细胞核并且在施加赤霉素后迅速降解,表明该基因编码蛋白参与赤霉素信号通路。     

Construction of a bacterial artificial chromosome library for Gossypium herbaceum var. africanum

Gossypium herbaceum var. africanum is the only wild cotton species within the cultivated diploid G. herbaceum. As the A sub-genome donor of tetraploid cotton, it is characterized by its resistance to insects, diseases, and other adversities. We have constructed the first bacterial artificial chromosome library (BAC) for G. herbaceum var. africanum. With high quality and broad coverage, this library includes 75000 clones, with an average insert size of about 115 kb and fewer than 4% empty clones. Our library is approximately five-fold the size of the A-genome (1667 Mb) and it provides 99.3% probability for isolating genes of interest or their sequences. Using nine SSR markers that are located on five different chromosomes and linked with resistance to Verticillium wilt, seven of nine could amplify the 40 superpools and got 1-14 hits. Because of its moderate wide coverage and relative large insert size, this library will be an important genomic resource for classifying and analyzing the evolution of cotton species, as well as for isolating disease-resistance genes and control elements.     

亚洲棉5号染色体RGAs克隆与分析

棉花是最主要的天然纤维作物,深入进行棉花基因组研究具有重要意义.采用酶解、前后低渗和轻压相结合的方法制备亚洲棉染色体中期膜载片,激光法分离亚洲棉第5号单染色体,建单染色体扩增池后克隆其抗病基因同源序列(RGAs),获得P7、P12、P19和P23等4个序列.序列比对和聚类分析表明,这4条序列均为NBS-LRR类RGAs,P7、P12、P19聚成一类,它们之间的同源性很高,P23聚成另一类,与黑松的RPS2和油菜的RGA30同源性较高.为该染色体分子标记开发、基因克隆乃至全序列测定奠定基础.     

新疆海岛棉新海15体细胞胚胎的发生及植株再生

为了扩展可再生棉花的基因型,选取新疆自育海岛棉品种新海15的胚珠为外植体,利用组织培养的方法进行再生体系的建立。结果表明:含0.5mg/L KT和0.5mg/L 2,4-D的MSB培养基,在暗培养条件下可诱导胚珠,产生初始愈伤;愈伤分化则以含0.05/0.1mg/L KT和0.1mg/L 2,4-D的MSB培养基效果较佳;选取浅黄色、结构疏松的愈伤组织在含较高浓度IBA和较低浓度KT、2,4-D的3种调控培养基上依次继代,以此实现胚性愈伤组织的增殖及细胞状态调控;液体悬浮培养和干燥胁迫处理均有利于胚性愈伤的体细胞胚胎诱导;子叶胚的萌发及植株再生则以含谷氨酰胺和天冬酰胺的1/2 MSB培养基效果较佳。     

Cloning and characterization of a gene encoding cysteine proteases from senescent leaves of Gossypium hirsutum

A gene encoding a cysteine proteinase was isolated from senescent leave of cotton (Gossypium hirsutum) cv liaomian No. 9 by utilizing rapid amplification of cDNA end spolymerase chain reaction (RACE-PCR), and a set of consensus oligonucleotide primers was designed to anneal the conserved sequences of plant cysteine protease genes. The cDNA, which designated Ghcysp gene, contained 1368 bp terminating in a poly(A)^ trail, and included a putative 5‘(98 bp) and a 3‘(235 bp) non-coding region. The opening reading frame (ORF) encodes polypeptide 344 amino acids with the predicted molecular mass of 37.88 kD and theoretical pl of 4.80. A comparison of the deduced amino acid sequence with the sequence in the GenBank database has shown considerable sequence similarity to a novel family of plant cysteine proteases. This putative cotton Ghcysp protein shows from 67% to 82% identity to the other plants. All of them share catalytic triad of residues, which are highly conserved in three regions. Hydropaths analysis of the amino acid sequence shows that the Ghcysp is a potential membrane protein and localizes to the vacuole, which has a transmembrane helix between resides 7-25. A characteristic feature of Ghcysp is the presence of a putative vacuole-targeting signal peptide of 19-amino acid residues at the N-terminal region. The expression of Ghcysp gene was determined using northern blot analysis. The Ghcysp mRNA levels are high in development senescent leaf but below the limit of detection in senescent root, hypocotyl, faded flower, 6 d post anthesis ovule, and young leaf.     

卡那霉素对棉花愈伤组织诱导和生长的影响

卡那霉素对棉花愈伤组织的诱导和生长均有明显的抑制作用,随着卡那霉素浓度的增加,愈伤组织形成的频率降低,增殖倍数减少,当浓度超过时５０ｍｇ／Ｌ时,愈伤组织的诱导与生长几乎完全受到抑制,不同外体对卡那霉素的敏感程度不同,子叶较强,下胚轴稍弱。     

Construction and initial analysis of five Fosmid libraries of mitochondrial genomes of cotton （Gossypium）

Cotton （Gossypium） is an important crop providing textile fiber and edible oil. To gain the insights into mechanism of the cyto- plasmic male sterility （CMS） inheritance, we constructed five fosmid libraries of mitochondrial genomes from mitotype of G. harknessii Brandegee. （one CMS line and its restorer）, mitotype of G. hirsutum L. （one CMS line and its maintainer）, and G. bar- badense L. The numbers of the clones in these libraries ranged from 1152 to 2016 with an average insert size of 36.2 to 38.4 kb, equivalent to 70-119.3 mitogenomes. The libraries were screened with 28 markers derived from the conservative sequences and yielded 22, 19, 26, 21, and 23 positive clones, respectively. These positive clones were used to construct the physical map of G. harknessii Brandegee. CMS line and G. barbadense L. mitogenomes that shared six syntenis regions. A total of 30 genes in nine clusters showed conservative and had high similarity with those in the mitochondrial genomes of cotton, Carica papaya, Cucur- bita pepo and Nicotiana tabacum. Further investigation indicated that gene rrn26 had two copies in all five cotton mitogenomes, while genes atpl, rrn5 and rrn18 had two copies only in G. barbadense L. The positive clones and physical map are considered being useful resources in cotton genomics research.     

亚洲棉全基因组中NAC类转录因子基因的鉴定与分析

为了开发棉花NAC基因资源,本文利用生物信息学方法在亚洲棉基因组中预测了138个NAC基因,根据其在染色体上的位置关系命名为Ga NAC001-Ga NAC138,所有Ga NAC基因分布于亚洲棉13条染色体上。根据Ga NAC蛋白的序列相似性及系统进化分析,将亚洲棉Ga NAC蛋白分为11个亚家族,每个亚家族的Ga NAC蛋白数目为4-25个。基因结构分析发现,大部分(63.7%)Ga NAC基因含有2个内含子。比较亚洲棉与陆地棉、雷蒙德氏棉NAC蛋白的同源性,发现亚洲棉与雷蒙德氏棉NAC蛋白的匹配程度高于陆地棉,平均序列一致性分别为93.9%和81.2%,一些NAC基因(58/138)在棉属的进化过程中高度保守,一些(37/138)则变异程度较大,可能是生物体为了适应环境的变化产生了新的功能。本研究结果为亚洲棉及陆地棉NAC转录因子基因的后续深入研究提供了重要参考。