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31.
采用Illumina HiSeqTM2500高通量测序技术,获得泡桐维管形成层及木质部区组织转录组的109021918条clean reads(16.35 Gb)。将clean reads从头组装得到104432个单基因簇(Unigene),平均长度662 nt。将组装得到的Unigenes与公共数据库进行序列比对,分别有40789(Nr:39.05%)、31675(NT:30.33%)、15539(COG:14.87%)、29168(GO:27.93%)、16316(KEGG:15.62%)、30499(SwissProt:29.20%)以及28828(Pfam:27.6%)个Unigenes获得功能注释。通过与GO数据库的比对分析,注释的29168个Unigenes归于生物过程、细胞组分及分子功能三大类的55个功能组;15539条Unigenes注释到COG数据库,被分为25个类别中;基于KEGG数据库可将16316个Unigenes归于130个代谢途径。此外,在泡桐的维管形成层及木质部区转录组中共检测出16118个简单序列重复(SSR)位点。为进一步挖掘泡桐重要功能基因提供了大量数据。  相似文献   
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The enzyme carbonic anhydrase (CA) (EC 4.2.1.1) catalyzes the reversible conversion of CO2 to HCO3- and has been shown to be involved in photosynthesis. The enzyme has been shown in animals, plants, eubacteria and viruses, but similar reports on the evidence for CA activity in tree plants does not be appear to be available. In the preliminary analyses of the work, the CA activity in leaf extracts from the tree species Paulownia tomentosa Steud. (introduced in Bulgaria) is described. A connection between CA activity and the rate of photosynthetic CO2 fixation is shown. In the second portion of the work, the effect of 10(-4) mol/L and 10(-2) mol/L dimethylsulfoxide (DMSO) on the zinc accumulation in leaves is demonstrated. It is suggested that CA activity is an indicator of the level of physiologically active zinc in leaves of P. tomentosa Steud. A connection between the process of zinc accumulation in leaves and the activity of the enzymes CA and glycolate oxidase (GO) (EC 1.1.3.1) is established.  相似文献   
34.
Seeds of the empress tree ( Paulownia tomentosa Steud.) were imbibed for two weeks in darkness at constant temperatures (18, 23 or 28°C), and then irradiated with red light for 5 min. Germination was poor if it took place at the same temperature as imbibition, but a high percentage was achieved if the seeds were exposed to higher or lower temperatures before they were irradiated. Maximum germination was obtained when the difference between pretreatment and imbibition was about 10°C. The effect increased with the duration of the pretreatment and was optimal at 24 h. The effect decreased as the time lapse between temperature pretreatment and red light irradiation increased, and it was lost after two days. If pretreatment was shorter than 24 h (12 h). a high percent of germination was obtained by alternating pretreatment and imbibition temperatures. The germination of seeds imbibed in 40% heavy water was also stimulated by temperature pretreatments. Light and temperature also exhibited an interactive effect in the germination of seeds that were imbibed in darkness for only 3 days. For each of the germination phases there was a temperature at which the time needed for 50% germination was the shortest, namely 35°C during imbibition, 37.5°C in the period of Pfr activity. and 32.5°C during radicle protrusion. The data obtained are shortly discussed in relation to the domestication of empress tree in Southern Europe.  相似文献   
35.
Grubišié, D., Konjevié, R. and Neškovié, M. 1988. The effect of some growth regulators on light-induced germination of Paulownia tomentosa seeds. - Physiol. Plant. 72: 525–528.
The germination of Paulownia tomentosa Steud. (Empress tree) seeds can be induced either by red light (R) or by exogenously applied gibberellic acid (GA3). The R induced germination is completely suppressed by far red irradiation, abscisic acid (ABA) or by growth retardants such as ancymidol, tetcyclacis and paclobutrazol, though not by AMO 1618 or chloro-choline chloride (CCC). The inhibition caused by far red light (FR) and growth retardants can be overcome by GA3, while the ABA-induced inhibition can be reversed by fusicoccin (FC), which does not reverse the inhibition caused by FR or growth retardants. It is noteworthy that the germination of light insensitive wheat, corn, alfalfa and mung bean seeds is not inhibited by growth retardants.  相似文献   
36.
用荧光显微技术对酶法分离的胚囊进行了三方面的研究:(1)利用与DNA结合的荧光染料Hoechst 33258对金鱼草、蚕豆、芝麻、烟草、龙葵等植物的分离胚囊??染色,可以观察胚囊中各组成细胞的核以及合子和胚乳的核。(2)用金胺O和樱草黄两种荧光染料染色,证明胚囊壁中含有耐果胶酶与纤维素酶作用的成分,可能是角质,因而虽经上述酶处理仍能保持胚囊的整体性。(3)用脱色苯胺蓝染色观察了被果胶酶分离的泡桐大孢子发生的各期材料,对这一过程中胼胝质的动态作了描述。以上各项实验表明:酶法分离技术与荧光显微技术相结合,是研究胚囊细胞生物学的一种简便有效的方法。  相似文献   
37.
应用Eberhart的性状值回归参数b_i及S_(di)~2、Tai的结构模型参数和,Ecovalence(W)值等参数,对泡桐品种多点试验林8个无性系生长量的基因型稳定性和生长适应性进行了分析。并结合生产力对各无性系进行了综合评定。结果表明:选出的8112-3和8112-1属速生、稳定、适应性强的无性系;8112-4和7606-6属于速生但不稳定的无性系,只适宜于较好的环境条件。经聚类分析将采用的8个参数明显地归为三类,类间相互独立,可分别用于评价基因型的生产力、遗传稳定性和适应性。  相似文献   
38.
Paulownia taiwaniana, the widely cultivated, commercially important tree, has been suspected of being of hybrid origin at least since its original publication in 1975. Evidence in support of this thesis, derived from a number of different investigations, is presented in this paper.—Strong evidence comes from a controlled pollination study of the two supposed parental species,P. kawakamii andP. fortunei. F1 seedlings, derived from reciprocal crosses between the suspected parents, exhibited identical banding patterns for a number of enzymes (such as SKDH, GOT, and IDH) withP. taiwaniana, when separated by electrophoresis. Furthermore, comparative morphological studies of trichomes and wood parenchyma patterns between the purported parents andP. taiwaniana reveal that this latter qualitatively exhibits characteristics that combine features of both of the suspected parental types. Biochemically, eight enzyme systems were compared in the three species here under discussion, and, without exception, the electrophoretic banding patterns exhibited byP. taiwaniana represented a combination of the alleles of the other two species. Perhaps the most convincing evidence comes from a genetic analysis of the progeny obtained by selfingP. taiwaniana. Genotypic segregation of the offspring based on a single locus each of SKDH and PGI fit the 1:2:1 hypothesis. Genotypic segregation of the offspring based on two loci each of SP and GOT fit the ratio of 3:6:3:1:2:1. This, taken in conjunction with the other data presented, clearly suggests thatP. taiwaniana is a hybrid involvingP. kawakamii andP. fortunei.  相似文献   
39.
为寻找新的能产生抗生素的植物内生真菌,采用3种培养基对毛泡桐进行内生真菌的分离,以大肠埃希菌、枯草芽胞杆菌、金黄色葡萄球菌、青枯假单胞菌为指示菌,利用琼脂块法和滤纸片扩散法筛选能抑制细菌的菌株;通过形态特征和ITS序列分析鉴定高活性菌株。结果从毛泡桐的根、茎、叶中共分离得到46株内生真菌,至少能抑制一种指示菌的有9株,其中菌株KLBMP-Pt630、KLBMP-Pt675和KLBMP-Pt686活性较强,鉴定结果显示:KLBMP-Pt630为三线镰刀菌、KLBMP-Pt675为棒曲霉、KLBMP-Pt686属于肉座菌目真菌。  相似文献   
40.
The effects of ethylene and CO2 on shoot regeneration in excised leaf cultures of Paulownia kawakamii were examined. When both the gases were prevented from accumulating in the headspace of cultures using mercuric perchlorate and potassium hydroxide traps, shoot regeneration frequency improved and callus production was reduced compared to the control and cultures with only one of the gases trapped. Incorporation of either aminoethoxyvinylglycine (AVG) or 1-amino-cyclopropane-1-carboxylic acid (ACC) in the culture medium caused significant reduction in shoot regeneration. There was profuse callus production in the presence of high amounts of ACC, which was accompanied by over sixfold increase in the rate of ethylene production. However, in the presence of AVG callus production was delayed and shoot regeneration decreased, suggesting that low levels of ethylene might be needed for de novo shoot bud induction in Paulownia cultures.Abbreviations IAA Indole-3-acetic acid - MP mercuric perchlorate - AVG aminoethoxyvinylglycine - ACC 1-aminocyclopropane-1-carboxylic acid  相似文献   
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