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1.
4种蚜虫对异色瓢虫生长发育和繁殖的影响   总被引:1,自引:0,他引:1  
为明确桃蚜、萝卜蚜、胡萝卜微管蚜、瓜蚜对异色瓢虫种群扩繁的适宜性,在实验室条件下,以4种蚜为食料构建异色瓢虫两性生命表,研究不同蚜虫对异色瓢虫生长发育和繁殖的影响。结果表明: 取食不同蚜虫,异色瓢虫未成熟期由长到短依次为萝卜蚜(18.18 d)、瓜蚜(17.48 d)、胡萝卜微管蚜(16.23 d)、桃蚜(15.77 d);成虫前期存活率由高到低依次为胡萝卜微管蚜(88.3%)、桃蚜(86.7%)、萝卜蚜(55.0%)、瓜蚜(55.0%);成虫繁殖力由高到低依次为胡萝卜微管蚜(1750.5粒)、桃蚜(1441.5粒)、瓜蚜(1006.3粒)、萝卜蚜(965.2粒);成虫寿命由长到短依次为胡萝卜微管蚜(78.8 d)、桃蚜(63.1 d)、瓜蚜(54.3 d)、萝卜蚜(48.4 d);异色瓢虫种群内禀增长率rm由高到低依次为桃蚜(0.19)、胡萝卜微管蚜(0.18)、萝卜蚜(0.14)、棉蚜(0.14);净增值率R0由高到低依次为胡萝卜微管蚜(895.83)、桃蚜(600.62)、萝卜蚜(273.47)、棉蚜(268.33)。4种蚜虫中,胡萝卜微管蚜和桃蚜更有利于异色瓢虫种群扩繁。  相似文献   

2.
We observed expression patterns of hedgehog (hh), wingless (wg), and decapentaplegic (dpp) during gut development of Gryllus bimaculatus (the cricket), a typical hemimetabolous insect, and compared with those observed in Drosophila, a typical holometabolous insect. Gryllus hh(Gbhh) and Gbwg are expressed in both foregut and hindgut, while Gbdpp is expressed only in the hindgut: at the boundaries between the small and large intestine, and between the large intestine and rectum. Although the expression patterns of Gbhh and Gbwg are essentially comparable to those observed in Drosophila, the expression pattern of Gbdpp differs from those of the Drosophila dpp.  相似文献   

3.
The chemical composition of essential oils isolated from aerial parts of seven wild sages from Western Canada – Artemisia absinthium L., Artemisia biennis Willd., Artemisia cana Pursh, Artemisia dracunculus L., Artemisia frigida Willd., Artemisia longifolia Nutt. and Artemisia ludoviciana Nutt., was investigated by GC–MS. A total of 110 components were identified accounting for 71.0–98.8% of the oil composition. High contents of 1,8-cineole (21.5–27.6%) and camphor (15.9–37.3%) were found in Artemisia cana, A. frigida, A. longifolia and A. ludoviciana oils. The oil of A. ludoviciana was also characterized by a high content of oxygenated sesquiterpenes with a 5-ethenyltetrahydro-5-methyl-2-furanyl moiety, of which davanone (11.5%) was the main component identified. A. absinthium oil was characterized by high amounts of myrcene (10.8%), trans-thujone (10.1%) and trans-sabinyl acetate (26.4%). A. biennis yielded an oil rich in (Z)-beta-ocimene (34.7%), (E)-beta-farnesene (40.0%) and the acetylenes (11.0%) (Z)- and (E)-en-yn-dicycloethers. A. dracunculus oil contained predominantly phenylpropanoids such as methyl chavicol (16.2%) and methyl eugenol (35.8%). Artemisia oils had inhibitory effects on the growth of bacteria (Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermidis), yeasts (Candida albicans, Cryptococcus neoformans), dermatophytes (Trichophyton rubrum, Microsporum canis, and Microsporum gypseum), Fonsecaea pedrosoi and Aspergillus niger. A. biennis oil was the most active against dermatophytes, Cryptococcus neoformans, Fonsecaea pedrosoi and Aspergillus niger, and A. absinthium oil the most active against Staphylococcus strains. In addition, antioxidant (beta-carotene/linoleate model) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities were determined, and weak activities were found for these oils.  相似文献   

4.
为了揭示兴安落叶松针叶光合作用对环境变化响应的分子机制,采用高通量测序技术,对生长环境差异明显的4个样地[塔河(52°52′ N)、松岭(50°72′ N)、黑河(49°22′ N)和带岭(47°08′ N)]兴安落叶松针叶进行转录组测序,并比对不同样地树木针叶的差异表达基因(DEGs)。结果表明: 共获得高质量短读序282428811条,其中在塔河-松岭、塔河-黑河、塔河-带岭、松岭-黑河、松岭-带岭、黑河-带岭6个对比组中,分别筛选出16915、18812、28536、20635、29957和23617条差异表达基因。在KEGG代谢通路分析中,光合作用通路中编码光系统Ⅱ(PSⅡ)的Psb基因家族的9个基因(即PsbBPsbKPsbOPsbPPsbQPsbSPsbWPsb27和Psb28)及编码F型ATP酶的3个基因(即ATPF1A, atpAATPF1G, atpGATPF1D, atpH)均随样地间的环境差异增大而呈现明显上调;氮代谢通路中编码谷氨酰胺合成酶的基因(glnA, GLUL)、硝酸还原酶的基因(NR)、碳酸酐酶的基因(cynT,can)也呈现同样的上调。DEGs和上调基因的数量均随样地环境变化增大而增多,进而导致了兴安落叶松针叶光合能力在样地间的差异。  相似文献   

5.
《植物生态学报》1958,44(8):864
为明确毛白杨(Populus tomentosa)不同方位夜间蒸腾量(Nt)及茎干充水量(Sr)等夜间液流活动的规律, 探究不同方位NtSr的主要影响因子, 该研究使用热扩散的方法监测了宽窄行模式下栽植的毛白杨茎干不同方位夜间液流, 并用图像法区分NtSr。使用自动气象站和机械式张力计监测太阳总辐射(Rs, kW·m-2)、空气温度(Ta, ℃)、空气相对湿度(RH, %)、风速(v, m·s-1)、土壤水势(ψ, kPa)等环境因子。通过比较各方位的NtSr等液流活动的大小情况及其与环境因子之间的相关性得到方位间夜间液流的差异性以及各方位夜间液流的主要影响因子。结果显示: 宽行距位于东侧的样树西方位的NtSr均最大, 其中西方位的Sr显著大于其他3个方位; 北方位的Nt显著小于其他3个方位; 其他方位间的NtSr无显著差异; 各方位夜间茎干充水量占夜间液流量的比例(Sr/Q)无显著差异。宽行距位于西侧的样树西方位的NtSr亦均最大, 其中西方位的Sr显著大于东方位和南方位; 南方位的Nt最小, 显著小于西方位和北方位, 其他方位间的NtSr无显著差异; 南方位的Sr/Q显著大于其他3个方位。各方位的NtSr均与水汽压亏缺(VPD)有显著的正相关关系, 部分方位NtSrTaRH有显著相关关系, 没有任何方位NtSrvψ有显著相关关系。NtSr方位间的差异(NtCVSrCV)与VPDTaRHvψ均无显著相关关系。此外, Sr受白天的液流活动的影响显著。综上所述, 毛白杨不同方位NtSr等液流活动具有较大的差异, 且西方位是优势方位; VPD是影响各方位NtSr的主要气象因子。  相似文献   

6.
We have analyzed the relationship between autonomously replicating sequence (ARS) structure and function for three ARS (ARS605, ARS607 and ARS609) from chromosome VI of Saccharomyces cerevisiae by systematic XhoI-linker mutation in the ARS consensus sequence (ACS) and flanking sequences. All mutations that encroached upon the ACS destroyed ARS activity. DNA sequences stimulative for ARS function were identified on either side of the ACS of ARS605 and only on the 3'-side of the ACS of ARS607. In ARS609, however, no such stimulative sequences were observed. Base substitutions complementary to the wild-type sequence of those stimulative regions, in ARS605 and ARS607, that did not change the AG of unwinding nor affected ARS activity suggests that these regions have, at least, a function as DNA-unwinding elements (DUE). ARS605, ARS607 and ARS609 DNA are of low AG value and showed hypersensitivity to single-strand-specific nuclease when inserted in negatively supercoiled plasmid. Linker mutations inhibitory for ARS activity (5L11 and 7L14) also caused significant changes in local nucleotide (nt) sensitivity within the ACS and its adjoining regions. Complementary base substitutions, however, did not affect these changes in local nt sensitivity. These results imply that the stimulative regions flanking the ACS are necessary to produce an optimum conformation around the ACS which may be important for full ARS activity.  相似文献   

7.
[10D-3H; 3-14C]- and [10L-3H; 3-14C]arachidonic acids were incubated with human polymorphonuclear leukocytes and with human platelets. Leukotriene B4 and 5(S),12(S)-dihydroxy-6trans,8cis,10trans,14-cis-eicosatetraenoic acid (5,12-DHETE) were isolated and the 3H/14C ratios determined. It could be concluded that the 10D (pro-R)-hydrogen is eliminated in the conversion of 5(S)-hydroperoxy-6trans,8cis,11cis,14cis-eicosatetraenoic acid into leukotriene A4 whereas in the conversion of arachidonic acid into 5,12-DHETE the 10L (pro-S)-hydrogen is lost. Incubation of the doubly labeled arachidonic acids with human platelets confirmed and extended previous data on the stereochemistry of the hydrogen removal from C-10 during the conversion into 12(S)-hydroperoxy-5cis,8cis,10trans,14cis-eicosatetraenoic acid, i.e., the 10L (pro-S)-hydrogen is eliminated and the 10D (pro-R)-hydrogen retained.  相似文献   

8.
刘燕  李玉玲 《人类学学报》2022,41(5):875-882
目前有关儿童青少年坐高、下肢长及其比值的报道多为非双生子人群的研究。为了解遗传和环境因素对儿童青少年坐高、下肢长及坐高与下肢长比值影响的相对大小,我们对796对6~18岁双生子的身高和坐高进行了测量,计算下肢长及坐高与下肢长比值,采用结构方程模型分析其遗传和环境相对效应。结果发现,校正年龄后,男女15~18岁年龄组坐高和下肢长的遗传度(0.63~0.78)均分别高于同性别低年龄段儿童青少年(0.31~0.68);坐高与下肢长比值的遗传度除9~11岁女生(0.84)外,其他年龄组均较低(男0.16~0.46,女0.21~0.57);共同环境因素和特殊环境因素对6~14岁儿童青少年各指标的作用较大。本研究提示,在快速发育时期,坐高、下肢长和坐高与下肢长比值对环境因素更为敏感,遗传度较低;机体越成熟,其遗传效应更强。  相似文献   

9.
王本刚  吕执  徐倩  刘永锋 《遗传》2017,39(1):22-31
基因间SNP-SNP的交互作用较单一SNP对于疾病的预警作用可能会达到更优的检测效能。本研究探讨了核苷酸切除修复(NER)系统基因中SNP交互作用对移植排斥反应发病风险的预警作用。通过Sequenom MassARRAY平台进行基因分型,对8个NER基因中的38个多态进行了检测,包括XPAXPCDDB2XPB (ERCC3)、XPD (ERCC2)、ERCC1XPF (ERCC4)和XPG (ERCC5)基因。单体型分析结果显示,XPA rs3176629-rs2808668 C-T单体型以及ERCC5 G-C-C-T和G-C-T-C单体型可以增加移植排斥反应的发病风险(分别为OR = 1.81,OR=7.72和OR=3.46),而ERCC5 rs2094258-rs751402-rs2296147-rs1047768 A-C-T-T单体型降低了该风险(OR = 0.35)。多因素Logistic回归与多因子降维(MDR)分析均表明,ERCC2 rs50871、ERCC5 rs1047768和XPC rs2228001多态对于发生移植排斥反应存在基因间SNP-SNP的交互作用。因此,XPC rs2228001、ERCC2 rs50871、ERCC5 rs1047768三者的交互作用与移植排斥反应的发病风险相关。  相似文献   

10.
We compared the pathogenicity of the entomopathogenic nematodes Heterorhabditis bacteriophora, Steinernema glaseri, and S. scarabaei against third instars of 12 white grub species. The Japanese beetle (Popillia japonica) was highly susceptible to all nematode species. Oriental beetle [Exomala (=Anomala) orientalis], European chafer (Rhizotrogus majalis), Asiatic garden beetle (Maladera castanea), and the May/June beetles Phyllophaga crinita, Ph. congrua, and Ph. (Subgenus Phytalus) georgiana were highly susceptible to S. scarabaei but had mediocre to low susceptibility to H. bacteriophora and S. glaseri. The black turfgrass ataenius (Ataenius spretulus) was very susceptible to H. bacteriophora but had mediocre susceptibility to S. glaseri and S. scarabaei. Northern (Cyclocephala borealis) and southern masked chafer (C. lurida) had mediocre and southwestern masked chafer (C. pasadenae) and green June beetle (Cotinis nitida) had low susceptibility to all nematode species.  相似文献   

11.
Thelazia gulosa, Thelazia rhodesi and Thelazia skrjabini are nematodes transmitted by some species of Musca (Diptera: Muscidae) which cause ocular infestations in bovines. Differences in the rDNA of these species were determined by a PCR using different sets of relatively conserved oligonucleotide primers. PCR on the first internal transcribed spacer (ITS-1) revealed differences in size in Thelazia species (437 bp for T. gulosa, 370 bp for T. rhodesi and 506 bp for T. skrjabini) while the DNA control of Musca spp. was not amplified. The ITS-1 amplicons of the three species were sequenced and then analysed. The GC contents ranged from 26 to 36% and the level of differences in the nucleotide sequences of ITS-1 was lower between T. skrjabini and T. gulosa (39%) than the latter and T. rhodesi (49–56%). Restriction fragment length polymorphism (RFLP) of ITS-1 amplicons was also carried out and the restriction profiles compared. Clear genetic differences among the three Thelazia examined were demonstrated by using the enzymes HpaII, CpoI and SspI. This PCR–RFLP for the delineation of T. gulosa, T. rhodesi and T. skrjabini offers prospects as a molecular epidemiological tool to study parasite transmission patterns and prevalence.  相似文献   

12.
何荣健  明燕  姚莉梅  朱青青  江龙 《菌物学报》2021,40(10):2843-2853
为探析和比较梵净山国家自然保护区矮林生态系统中丛枝菌根(arbuscular mycorrhizal,AM)真菌群落特征,对6种山顶苔藓矮林群落(山樱-山矾Prunus-Symplocos、杜鹃-槭树Rhododendron-Acer、花楸-杜鹃Sorbus-Rhododendron、槭树Acer、黔稠Cyclobalanopsis stewardiana、杜鹃Rhododendron)土壤进行AM真菌分离、鉴定和分析。结果表明:梵净山山顶苔藓矮林群落共有13属32种AM真菌,包括无梗囊霉属Acaulospora 13种、球囊霉属Glomus 5种、近明球囊霉属Claroideoglomus 2种、多样孢囊霉属Diversispora 2种、隔球囊霉属Septoglomus 2种、原囊霉属Archaeospora 1种、双型囊霉属Ambispora 1种、内养囊霉属Entrophospora 1种、和平囊霉属Pacispora 1种、硬囊霉属Sclerocystis 1种、西维丁囊霉属Sieverdingia 1种、盾巨孢囊霉属Scutellospora 1种和巨孢囊霉属Gigaspora 1种,其中无梗囊霉属的分离频率、相对多度和重要值最高,分别是100%、65.90%和82.95%,为矮林区域的优势属,柯氏无梗囊霉为该区域的优势种;不同矮林间AM真菌群落结构组成差异显著,槭树矮林的孢子密度、菌根侵染率和Shannon-Wiener指数显著高于其他5种植物群落,黔稠矮林的孢子密度和物种丰富度最低,杜鹃矮林的AM真菌Shannon-Wiener指数和Simpson指数均为所有植物群落中最低,表明不同矮林类型对AM真菌群落结构具有重要影响。  相似文献   

13.
Seroprevalence of equine babesiosis in the Black Sea region of Turkey   总被引:1,自引:0,他引:1  
The prevalence of Theileria equi and Babesia caballi was determined in equid blood samples in five provinces of the Black Sea region of Turkey by using the indirect fluorescent antibody test (IFAT). Of 153 samples, 53 (34.6%) and 33 (21.5%) were seropositive to B. caballi and T. equi, respectively. In addition, 8 (5.2%) of samples were seropositive to both T. equi and B. caballi. Anti T. equi and B. caballi antibodies were detected in all five regions. The prevalence of B. caballi was higher than T. equi in all counties. Antibodies to T. equi and B. caballi were detected in horses of all ages, and there were no significant differences among age groups. Out of 84 horses, 32 (38.0%) were positive for B. caballi infection and 20 (23.8%) were positive for T. equi infection. Five horses (5.6%) were found to be seropositive to both B. caballi and T. equi. Of 38 donkeys, 14 (36.8%) were found to be positive for B. caballi infection and 5 (13.1%) positive for T. equi infection. In addition, 2 (5.2%) samples were seropositive for both T. equi and B. caballi infections. Out of 31 mules, 8 (25.8%) were positive for B. caballi infection and 8 (25 8%) positive for T. equi infection. One (3.2%) sample was seropositive for both T. equi and B. caballi infections. Of all the animals in this study, only 3 horses were infected by Rhipicephalus turanicus and Hyalomma detritum, and no haemoparasites were detected by microscopic examination.  相似文献   

14.
异担子菌属Heterobasidion种类是北半球针叶树最严重的森林病原菌,在世界范围内能侵染27种针叶树,对欧洲和北美洲的经营林已造成重大损失。基于传统形态学研究,认为异担子菌属有2个种,即多年异担子菌H. annosum和岛生异担子菌H. insulare,然而单孢交配实验研究证明2个种为复合种。分子系统发育分析研究表明:异担子菌属包括15个种,其中5个种为森林病原菌[冷杉异担子菌H. abietinum、多年异担子菌(狭义)H. annosum s. str.、变孔异担子菌H. irregulare、西方异担子菌H. occidentale和小孔异担子菌H. parviporum];10个种为腐生菌(淀粉孢异担子菌H. amyloideum、南洋杉异担子菌H. araucariae、阿曼德异担子菌H. armandii、南方异担子菌H. australe、岛生异担子菌H. insulare、林芝异担子菌H. linzhiense、东方异担子菌H. orientale、拟岛生异担子菌H. subinsulare、拟小孔异担子菌H. subparviporum和西藏异担子菌H. tibeticum)。多年异担子菌(狭义)H. annosum s. str.、小孔异担子菌H. parviporum和冷杉异担子菌H. abietinum分布于欧洲,分别是松属、云杉属和冷杉属林木的病原菌。变孔异担子菌H. irregulare和西方异担子菌H. occidentale分布于北美洲,前者侵染松属和柏属树木,后者侵染冷杉属、铁杉属、黄杉属和巨杉属树木。虽然广义的多年异担子菌H. annosum sensu lato曾在我国报道,但基于目前研究结果表明该种为拟小孔异担子菌H. subparviporum。目前世界上最具侵染力的5种病原菌即狭义的多年异担子菌H. annosum s. str.、小孔异担子菌H. parviporum、冷杉异担子菌H. abietinum、变孔异担子菌H. irregulare和西方异担子菌H. occidentale还未在我国发现,也未列为对外检疫对象,因此建议将其列为进境植物检疫性有害生物。RNA聚合酶II大亚基序列(RPB1)在异担子菌属种类鉴定中敏感性和特异性最高,研究证明该分子方法可应用于鉴别不同异担子菌种类的有效基因标记,在海关部门进行原木和木质产品的检疫中可运用该分子标记进行林木病原异担子菌的检测。  相似文献   

15.
The absolute configuration at C-12 of pittosporatobiraside A and B isolated from the leaves of Pittosporum tobira was determined to be S on the basis of the exciton chirality of their dibenzoate derivative. The structures of the two glycosides were thus established to be (1S,9S,10S,11S,12S,14R,16R)-12-[(Z)-2-methyl-1-oxo-2-butenyl]-6,14-dimethyl-2-methylene-9-(1-methylethyl)-15,17-dioxatricyclo[8.7.0.011,16]heptadec-5-en-13-one and (1S,9S,10S,11S,12S,14R,16R)-12-(3-methyl-1-oxo-2-butenyl)-6,14-dimethyl-2-methylene-9-(1-methylethyl)-15,17-dioxatricyclo [8.7.0.011,16]heptadec-5-en-13-one, respectively.  相似文献   

16.
红曲霉属Monascus具有重要的经济和生态价值,但对该属的物种识别和系统发育学研究有限。本研究首先对红曲霉属红色组内物种开展ITS和LSU序列的测定并综合分析,结合GenBank中相关物种序列及菌株的形态学特征,探讨红曲霉属的系统发育关系,鉴定出红色组3个种,弗罗里达组7个种。其次采用红曲霉色素表型控制基因簇部分基因pksKS序列进行分析,以期解决ITS和LSU等基因序列分析无法有效区分红色红曲与紫色红曲不同形态种的问题。通过分子克隆测序与直接测序结果的比较,以及对3个血红红曲菌株单核苷酸多态性的分析,解析了血红红曲种内遗传差异,首次在红曲霉属真菌中发现疑似红色红曲血红自然杂交种。最后综合ITS、LSU、pksKS序列和形态学分析的结果,统一了红曲霉属内物种的系统发育关系,确认红色组包括3个种:红色红曲M. ruber、紫色红曲M. purpureus、血红红曲M. sanguineus;发现3个变种:红色红曲发白变种M. ruber var. albidulus、紫色红曲橙色变种M. purpureus var. aurantiacus及紫色红曲火红色变种M. purpureus var. rutilus;弗罗里达组包括7个种:弗罗里达红曲M. floridanus、苍白红曲M. pallens、新月红曲M. lunisporas、阿根廷红曲M. argentinensis、累西腓红曲M. recifensis、黄色红曲M. flavipigmentosum、蜂蜜红曲M. mellicola。另外,发现1个疑似杂交种:红色红曲血红杂种M. ruber × sanguineus。结果表明,红曲霉属具有丰富的物种多样性,而且通过多基因和形态学分析可以将相近种区分开来。  相似文献   

17.
Effects of four antagonistic fungi (Paecilomyces lilacinus, Pochonia chlamydosporia, Trichoderma harzianum and Gliocladium virens) alone and together with a plant growth promoting rhizobacterium Pseudomonas putida, an arbuscular mycorrhizal fungus Glomus intraradices or with composted cow manure (CCM) were assessed on the growth of tomato and on the reproduction of Meloidogyne incognita in glasshouse experiments. Application of all antagonistic fungi (except G. virens), P. putida, G. intraradices or CCM caused a significant increase in the growth of plants without nematodes. However, use of either of these fungi, P. putida, G. intraradices and CCM against plants with nematodes caused a significant increase in tomato growth. Paecilomyces lilacinus caused a 42% increase in the growth of nematode-inoculated plants followed by P. chlamydosporia (36%), T. harzianum (18%) and G. virens (15%). CCM caused about 57% increase in the growth of nematode-inoculated plants followed by P. putida (37%) and G. intraradices (31%). Maximum increase (71%) in the growth of nematode-inoculated plants was observed when CCM was used with P. lilacinus. Moreover, P. lilacinus caused a high reduction (55%) in galling and nematode multiplication, while G. virens the least (25%). Use of P. putida also caused a 39% reduction in galling and nematode multiplication followed by CCM (34%) and G. intraradices (32%). Combined use of CCM with P. lilacinus caused maximum reduction (79%) in galling and nematode multiplication. Re-isolation of antagonistic fungi from nematodes revealed that P. lilacinus parasitised more females and eggs than other antagonistic fungi. Root colonisation by P. putida was increased with P. lilacinus, while colonisation by G. intraradices was reduced in the presence of antagonistic fungi.  相似文献   

18.
The grasses are the most important plant family for food production. Despite the domestication of Oryza sativa L. (rice), Triticum aestivum L. (wheat), Zea mays L. (corn), Hordeum vulgare L.(barely), Secale cereale L. (rye), Avena sativa L. (oats), Sorghum bicolor (L.) Moench (sorghum), Saacharum officinarum L. (sugar cane), Pennisetum glaucum (L.) R. Br. (pearl millet), Panicum virgatum L. (switchgrass), Eleusine coracana (L.) Gaertn (finger millet.) and Eragrostis tef (Zucc.) Trotter (tef), the family has not been widely studied biogeographically (Bouchenak-Khelladi et al.,2010). Other notable economic uses of grasses include landscaping, construction (primarily bamboos), and biofuel production (Miscanthus x giganteus J.M. Greef & Deuter ex Hodk. & Renvoize, Panicum L., and Zea L.).  相似文献   

19.
Most lichens of the family Teloschistaceae (Ascomycota) produce yellow-orange-red anthraquinone pigments. However, the genus Pyrenodesmia encompasses species in which anthraquinones are absent and replaced by a gray pigment Sedifolia-gray. It was shown recently that these species are related to taxa with both anthraquinones and Sedifolia-gray (Caloplaca xerica group, C. haematites group, and C. cretensis) and to species with a brown pigment instead of both anthraquinones and Sedifolia-gray (C. demissa, C. obscurella, and C. reptans). Nevertheless, relationships between mentioned anthraquinone-containing and anthraquinone-lacking species remained unclear. In total, 8 DNA loci from 41 species were used here to resolve these uncertainties. We concluded that C. demissa, C. obscurella, and C. reptans are rather distant from the core of Pyrenodesmia, and we place them outside of Pyrenodesmia sensu lato. Within Pyrenodesmia sensu lato, three lineages were revealed and recognized on a generic level: the genus Pyrenodesmia sensu stricto (21 species), the genus Kuettlingeria (14 species), which is resurrected here, and the genus Sanguineodiscus (4 species), which is newly described here. The genus Pyrenodesmia includes taxa that never contain anthraquinones, but Sedifolia-gray. It matches with the former C. variabilis group. Taxa of the genera Kuettlingeria and Sanguineodiscus have anthraquinones in their apothecia and Sedifolia-gray in their thalli. The genus Kuettlingeria includes the former C. xerica group plus C. cretensis and C. diphyodes. The genus Sanguineodiscus includes the former C. haematites group and C. bicolor. The identity of Kuettlingeria (Caloplaca) diphyodes was clarified and the name Pyrenodesmia helygeoides was resurrected. Twenty-four new combinations were proposed.  相似文献   

20.
The effects of mutations in five anterior gap genes (hkb, tll, otd, ems and btd) on the spatial expression of the segment polarity genes, wg and hh, were analyzed at the late blastoderm stage and during subsequent development. Both wg and hh are normally expressed at blastoderm stage in two broad domains anterior to the segmental stripes of the trunk region. At the blastoderm stage, each gap gene acts specifically to regulate the expression of either wg or hh in the anterior cephalic region: hkb, otd and btd regulate the anterior blastoderm expression of wg, while tll and ems regulate hh blastoderm expression. Additionally, btd is required for the first segmental stripe (mandibular segment) of both hh and wg at blastoderm stages. The subsequent segmentation of the cephalic segments (preantennal, antennal and intercalary) appears to be dependent on the overlap of the wg and hh cephalic domains as defined by these gap genes at the blastoderm stage. None of these five known gap genes are required for the activation of the labral segment domains of hh and wg, which are presumably either activated directly by maternal pathways or by an unidentified gap gene.  相似文献   

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