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171.
During Blattella germanica embryo development, the nutritive yolk protein vitellin is processed by a cysteine protease, which is activated proteolytically from a proprotease during acidification of yolk granules. A murine polyclonal antiserum was generated with the purified proprotease as the immunogen. The antiserum was made monospecific to proprotease by subtractive affinity chromatography using proprotease-free yolk proteins as ligand. The purified antibodies were employed to investigate the temporal and spatial expression of the proprotease during vitellogenesis and embryo development. Anti-proprotease-reactive peptides appeared in extracts of fat bodies and ovarian follicles of post-mating females, but not in fat bodies of males or the fat bodies or follicles of unmated females, suggesting that the proprotease is synthesized extraovarially. Use of the antibodies was extended to monitor the kinetics of proprotease disappearance during early embryo development. Arch. Insect Biochem. Physiol. 38:109–118, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
172.
锌对镉胁迫下马蔺生长、镉积累及生理抗性的影响   总被引:10,自引:0,他引:10  
通过溶液培养研究了不同浓度锌(Zn)对镉(Cd)胁迫下马蔺(Iris lacteavar. chinen-sis)生长、Cd积累及抗氧化酶活性等的影响.结果表明:加入1~100mg.L-1Zn后,Cd胁迫下马蔺地上部Cd含量变化不大,而地下部Cd含量显著增加并呈先增后降的趋势;1mg.L-1Zn处理下马蔺地下部Cd含量最高,比对照显著增加51.4%;Zn浓度高于1mg.L-1后Cd含量均出现不同程度的下降,但仍高于对照.与单独Cd处理(10mg.L-1)相比,添加低浓度Zn(1~10mg.L-1)后,马蔺地上部生物量和叶绿素含量呈增加趋势,丙二醛(MDA)含量降低;在10mg.L-1Zn处理下,叶绿素a、b含量达到峰值,分别增加5.21%和22.27%,MDA含量降低25.46%,表明低浓度Zn缓解了Cd对马蔺的毒害.随Zn浓度的增加,Zn对Cd毒害的缓解作用逐渐降低,当溶液中Zn达到一定浓度(100mg.L-1)时,马蔺毒害加重,其生物量、叶绿素含量均下降,MDA含量显著增加.在试验胁迫浓度范围内超氧化物歧化酶(SOD)、过氧化物酶(POD)活性始终呈增加趋势,表明马蔺在受到Cd胁迫及Cd-Zn共存的条件下SOD和POD起着重要的抗氧化保护作用.  相似文献   
173.
描述了福建省中北部山区鸢尾科(Iridaceae)鸢尾属(Iris)一新种:君子峰鸢尾(I. junzifengensis S. P. Chen, X. Y. Chen&L.Ma),新种与蝴蝶花(I. japonica Thunb.)、台湾鸢尾(I. formosana Ohwi)相近。与蝴蝶花不同之处在于叶片宽大,叶脉明显,表面粗糙;花为顶生稀疏总状聚伞花序,分枝2~6;花大,直径5.0~7.0 cm,花被裂片边缘波状皱褶,全缘,顶端稍有凹缺;蒴果三棱状圆柱形。与台湾鸢尾不同之处在于花小,花被裂片边缘波状皱褶,全缘,顶端稍有凹缺;蒴果三棱状圆柱形。形态特征比较及分子系统发育分析均支持该新种的成立。  相似文献   
174.
A comparative isoflavonoid analysis of 22 species of Iris, representing almost all the subgenera, and one species of its allied genus Balamcanda, B. chinensis (L.) DC. was carried out by TLC, with iridin, tectoridin, irigenin, tectorigenin, irisfloretin, dichotomin, wogonin, rhamnazin, apocynin, androsin being used as authentic compounds. The results show that the isoflavones are the characteristic constituents of Iris and Belamcanda. According to the distribution pattern of isoflavones, the Iris species here studied can be divided into 2 groups; one contains isoflavonoid aglycons, while the other contains both glycosides and isoflavonoid aglycons. From the point view of chemosystematics, subgen. Limniris contains isoflavonoid aglycons only and might be a natural group; subgen. Crossiris might be also a natural group when Iris speculatrix Hance is excluded; subgen. Pardanthopsis is similar to B. chinensis in the chemical constituent might be a primitive group in Iris and has close relationship with subgen. Crossiris, subgen. Xyridion and subgen. Iris. Based on the evidence from phytochemistry, palynology and cytology, Iris cathayensis Migo and I. mandshurica Pall. are considered intermediate groups between subgen. Limniris and subgen. Iris and I. speculatrix Hance an intermediate group between subgen. Limniris and subgen.Crossiris, while I. confusa Sealy and I. wattii Baker might be conspecific.  相似文献   
175.
中国北方鸢尾属植物叶片解剖结构特征及分类学价值研究   总被引:5,自引:1,他引:5  
王宏  申晓辉  郭瑛 《植物研究》2008,28(1):30-37
以中国北方生长的鸢尾属9种植物为研究对象,利用光学显微镜对叶表皮细胞形状及大小、气孔大小、气孔分布及气孔密度、气孔指数等叶表皮构造特征进行观察,并探讨了叶表皮特征在鸢尾属内各个亚属、亚组间的分类学价值,结果表明:表皮细胞的形状和大小显示了同亚属或同亚组植物之间较为明显的亲缘关系,在区分鸢尾属下不同亚属或亚组植物上也有一定的分类学价值。气孔密度和气孔指数在鸢尾属内分类学价值不大,但却能很好地反映不同鸢尾属植物与生境之间的密切关系。并从表皮构造特征上证实了野鸢尾与射干有很强的亲缘关系,且近于鸢尾属内的其他植物的结论;此外,通过对鸢尾属植物叶横切解剖结构的观察:从维管束、横切面形状、表皮细胞与角质层、乳突、气孔、气室大小、叶肉细胞的分化这7个较为明显的特征上的相关性和差异性,探讨了由于生境的不同而产生的植物形态结构的差异。  相似文献   
176.
荷兰鸢尾(Iris xiphium L. var. hybridum)的组织培养   总被引:1,自引:0,他引:1  
取荷兰鸢尾(IrisxiphiumL.var.hybridum)鳞茎片不同部位外植体块,接种于附加不同激素配比的基本培养基上,其中取自鳞茎片基部外植体块2mm×2mm×2mm,培养基为MS+BA1.0mg/L+NAA0.2mg/L的不定芽诱导率为最高(70%);最理想的增殖培养基为MS+BA2.0mg/L+NAA0.2mg/L。不定芽直径4~5mm,培养基为MS+BA0.2mg/L+NAA0.5mg/L有利于不定根的发生,诱导生根率达833%。试管苗不经练苗可直接出瓶,移栽于泥炭∶田土∶河沙=1∶1∶1(V/V)的基质中。  相似文献   
177.
光周期与温度对林地德国小蠊生长发育与繁殖的影响   总被引:2,自引:1,他引:1  
朱道弘  刘世大  赵吕权 《生态学报》2006,26(7):2125-2132
为弄清湖南株洲(北纬27°50′,东经112°54′)栖息于林地的德国小蠊(Blattella germanica)季节生活史策略,研究了光周期和温度对其若虫发育、龄数变异及成虫繁殖的影响。结果表明,德国小蠊的若虫发育明显受光周期的影响。长日条件(LD 16∶8h)下若虫发育最快,中间日长(LD 14∶10h)次之,短日条件(LD 12∶12h)下若虫发育最慢。将孵化后30日的若虫自长日条件向短日条件转移,则若虫发育受到明显抑制,反方向的转移,则若虫发育迅速。说明德国小蠊若虫存在滞育现象,短日条件诱导并维持滞育,长日条件解除滞育。若虫期经历的龄数受光周期和温度的影响,25℃的温度条件下,LD 16∶8h、LD 14∶10h及LD 12∶12h若虫期的龄数分别为7、8和9龄;长日条件下,30℃和25℃的若虫龄数为7龄,而20℃为9龄。根据实验室观察和林地调查结果,德国小蠊在湖南株洲1年发生1代,以滞育若虫越冬。30℃、25℃、20℃的温度条件下,卵鞘成活率分别为14.3%、90.1%和51.9%,高温和低温均不适合德国小蠊的繁殖。因此,可以认为控制若虫发育和龄数的光周期、温度反应的生态意义在于调控繁殖虫态和繁殖的适宜季节保持同步。  相似文献   
178.
Ten microsatellite loci isolated from Iris hexagona are described. All these loci are polymorphic, with three to 13 alleles across 24 individuals from a single natural population. Heterozygosity ranged from 0.125 to 0.870. Three loci depart significantly from Hardy–Weinberg equilibrium in our test population. The test population shows significant heterozygote deficiency in these and two other loci. Three loci exhibit significant linkage disequilibrium. These loci will be utilized to investigate patterns of genetic variation in the species throughout the Florida peninsula.  相似文献   
179.
The present article reports results of analysis of carboxylic acids in leaves of Iris species from Ukraine using a gas chromatography (GC) method with mass spectrometric (MS) detection (GC/MS). Carboxylic acids play significant roles in contemporary society as evidenced by multiple applications in fields of medicine, agriculture, pharmacy, food, and other industries. Study of natural plant products as a source of organic acids is of particular interest. Carboxylic acid composition of leaves of Iris hungarica Waldst. & Kit., Iris germanica L., Iris pallida Lam., and Iris variegate L. was studied for the first time applying GC/MS method. The mass spectrums of compounds were matched with NIST and WILEY Libraries. The GC/MS analysis revealed the presence of 26 common acids in the plant raw materials studied. The short-chain carboxylic acids, such as citric (1337.5–12364.4 mg/kg), malic (50.8–4558.0 mg/kg) and oxalic (1199.0–3435.2 mg/kg) acids were contained in significantly high quantity in all samples. Ferulic, p-coumaric and vanillic acids were the most abundant among phenolic acids. α-Linolenic acid was dominant in the leaves of I. germanica (869.5 mg/kg), I. pallida (753.3 mg/kg), and I. variegate (250.3 mg/kg) among polyunsaturated fatty acids, however, linoleic acid prevailed in the plant raw material of I. hungarica (1150.7 mg/kg). Since the leaves of Iris species studied contain carboxylic acids with diverse pharmacological activity, extracts of these raw materials are perspective for development food supplements and medicines.  相似文献   
180.
Irones are violet-scented ketonic compounds contained in the rhizome of certain species of iris. As cultivation of the iris tends to decrease, a selection program has been initiated to find the best performing clones in terms of growth and yield. Parallel to this selection, in vitro regeneration studies have been carried out in order to multiply interesting clones. A method of rapid multiplication by somatic embryogenesis associated with multibudding was developed. Callus was obtained from leaf bases, flower pieces or rhizome apices; the best explants were flower pieces. The induction media used to obtain embryogenic callus were Murashige & Skoog (1962) media. Assays with adding of proline in these media have showed that it could double the yield of embryogenic callus. The embryogenic expression medium was the Knudson's orchid agar (Knudson 1946) medium. Conformity of the plants obtained was checked by comparing their chemotypes with those of the mother plants.Abbreviations AIB indolyl butyric acid - BAP 6-benzylaminopurine - Kin 6-furfurylaminopurine - KN Knudson's orchid Agar - MS Murashige & Skoog medium - NAA naphthaleneacetic acid - N6 Chu et al. medium - Pro proline - 2,4-D dichlorophenoxyacetic acid  相似文献   
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