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1.
We investigated signal sources used by the parasitoid Lemophagus pulcher in locating and accepting larvae of its host, the lily leaf beetle, Lilioceris lilii. Olfactometer bioassays revealed that larvae with fecal shields, larvae without shields, the shield alone, and lily leaves damaged by L. lilii were all attractive to female parasitoids. In contact bioassays, L. pulcher females were attracted to shields and showed ovipositor probing independently of whether the larva underneath was L. lilii or a nonhost, suggesting that the shield plays a primary role in short-range host location and host acceptance by L. pulcher. The attractiveness of the shield is at least partly of a chemical nature, since shield extracts applied to dummies increased contact duration and induced ovipositor probing by L. pulcher. Another putative defense system of L. lilii, i.e., oral discharge which is emitted by disturbed larvae, was also attractive to experienced, but not to naive, female parasitoids. In all other tests, naive and experienced female L. pulcher responded to the same signal sources tested, suggesting that the host-selection behavior of this biological control candidate is governed largely by innate responses to host-associated cues.  相似文献   

2.
Summary The segregation of different isozymic loci was investigated in backcrosses and F2s in rye. The leucin aminopeptidase-1 (Lap-1), Aconitase-1 (Aco-1), Esterase-6 (Est-6), Esterase-8 (Est-8), and Endopeptidase-1 (Ep-1) loci were linked. The Aco-1, Est-6, and Est-8 loci have been previously located on the 6RL chromosome arm. The Lap-1 locus has been located on the 6RS chromosome arm. The results favor the gene order: Lap-1... (centromere)... Aco-1... Est-8... Est-6... Ep-1. The isoelectric focusing separations of aqueous extracts from mature embryo tissue of wheat-rye addition and substitution lines involving the chromosomes of cereal rye Secale cereale L. confirmed the gene location of locus Ep-1 on the 6RL chromosome arm. Screening of wheat-rye addition lines involving the chromosomes of Secale montanum revealed that Ep-1 locus is not located on chromosome 6R of S. montanum. These results are the first biochemical evidence of the translocation between chromosome arms 6RL/7RL in the evolution of S. cereale from S. montanum.  相似文献   

3.
Chen  Xiongwen  Zhou  Guangsheng  Zhang  Xinshi 《Plant Ecology》2003,164(1):65-74
Spatial characteristics of sixteen tree species were analyzed by theinformation from 287 permanent plots in 1986 and 1994 on North East ChinaTransect (NECT). Some species expanded and some retracted theirdistribution extents. Betula costata andPhellodendron amurense spread most fast toward west andeast, respectively. All tolerant tree species extended their frontiers and allintolerant tree species retracted their frontiers except Betulaplatyphylla. The distribution area decreased for all species exceptBetula costata, Juglans mandshurica,Ulmus spp. and Fraxinusrhynchophylla.The patch sizes of Pinus koraiensis, Populusdavidiana, Phellodendron amurense,Juglans mandshurica, Fraxinusmandshurica, Betula dahurica,Picea spp., Abies nephrolepis andLarixolgensis decreased, however, the patch sizes of Quercusmongolica, Betula costata, Acermono, Tilia spp., Ulmusspp., Betula platyphylla and Fraxinusrhynchophylla increased. The frequency pattern of Populusdavidiana, Betula platyphylla,Fraxinus rhynchophylla and Betuladahurica changed significantly(p< 0.05). The dominance pattern ofPopulus davidiana, Tilia spp.,Juglans mandshurica, Betulaplatyphylla, Betula dahurica andAbiesnephrolepis changed significantly(p < 0.05). The spatial correlation betweenspecies changed, such as the spatial correlation between Larixolgensis and Betula platyphylla, Acermono and Ulmus spp. increased. The possiblecause of these changes might be climate change, disturbances and habitat loss.  相似文献   

4.
Summary The segregation of isozymic loci for leaf peroxidases (L2Per) has been investigated in backcrosses and F2 offspring of rye lines having purple seeds (Ps) and monstrosum ears (mo). The Ps, L2Per-3b, mo, and L2Per-2 loci were linked. The Ps and mo loci have been previously located on the 2R chromosome, and the L2Per-3b and L2Per-2 loci have been located on the 2RS chromosome arm. The results favor the gene order Ps ... L2Per-3b ... mo ... L2Per-2 or Ps ... mo... L2Per-3b ... L2Per-2. The position of the loci relative to the centromere is still not known, but the obtained results suggest that the mo locus could be located on the 2RS chromosome arm. On the basis of previously reported linkage groups, the most probable arrangement of the loci located on chromosome 2R is: dw2 ... Ps ... (L2Per-3a ... L2Per-3b ... mo) ... L2Per-2. It has not been possible to know the position of L2Per-4 loci (also located on 2RS chromosome arm) relative to L2Per-3a and L2Per-3b loci.  相似文献   

5.
利用LI-6400光合仪测定新疆克里雅河流域荒漠-绿洲交错带自然生长的芦苇、柽柳、胡杨叶片的气体交换参数及环境影响因子,通过对比3种植物光合特性的差异及其与环境因子间的关系,探讨3种植物对荒漠环境的适应特性和机制。结果表明:(1)3种植物叶片Pn日变化均呈不对称的双峰曲线,"午休"现象明显,Pn日均值的大小依次为胡杨芦苇柽柳,种间差异不显著。(2)Tr、PAR和Gs与3种植物Pn的日变化存在极显著或显著的相关关系,其中影响芦苇Pn的主要因子是Tr、PAR和Gs,作用效应为TrGsPAR;影响柽柳Pn的主要因子是Tr、Gs,作用效应为TrGs;影响胡杨Pn的主要因子是Tr。(3)3种植物的光合作用对光强和CO2的响应特征可用二次方程描述;光补偿点和饱和点均为柽柳胡杨芦苇;CO2补偿点为胡杨柽柳芦苇,饱和点为胡杨芦苇柽柳。(4)3种植物的表观量子效率在0.0341—0.0411 mol/mol之间,羧化效率在0.0480—0.0546 mol m-2s-1之间。综合比较表明,3种干旱区植物在自然条件下日均净光合速率、光能利用率和CO2同化能力差异不显著,气孔限制是光合"午休"现象产生的主要原因;影响3种植物光合作用的主导因子各不相同,但Tr与Pn间的关系较其它因子更为密切。  相似文献   

6.
Desmids from 12 freshwater resources in the northern part of Thailand were investigated during 2002 to 2003. A total of 91 taxa were found. They belonged to 17 genera: Actinotaenium, Spirotaenia, Netrium, Gonatozygon, Pleurotaenium, Closterium, Euastrum, Micrasterias, Cosmarium, Cosmocladium, Stuarastrum, Staurodesmus, Xanthidium, Teilingia, Spondylosium, Hyalotheca and Desmidium. The water qualities in all the water resources were classified as oligotrophic to meso-eutrophic by trophic status. The taxa that could possibly be used as bioindicators of trophic state were Staurastrum gutwinskii, Spondylosium pandurifoemae, Cosmarium capitulum, C. mediosrobiculatum var. egranutum, S. tortum, Closterium gracile var. elongatum, C. kuetzingii and Closterium dianae var. dianae. The most frequently found taxa were Staurastrum limneticum var. burmense, S. tetracerum var. tetraerum, Pleurotaenium trabecula, Closterium ehrenbergii var. ehrenbergii and C. kuetzingii. The rare taxa in this study were Actinotaenium sp. Spirotaenia condensata, Pleurotaenium burmense var. dacchense and Micrasterias apiculata. Forty-one taxa of desmids were identified as new records for Thailand. Presented at the 6th Meeting of the Asian Pacific Society of Applied Phycology, Manila, Philippines.  相似文献   

7.
Macrolycus is a genus of net‐winged beetles with 69 species distributed in the eastern Palearctic and northernmost part of the Oriental region. The first molecular phylogeny of Macrolycus was produced using an rrnL + tRNA‐Leu + nad1 mtDNA fragment. The major lineages and species limits were identified with morphology and molecular data. We propose that Cerceros is a subgenus of Macrolycus to enable identification of all adult specimens in the genus without DNA sequencing. Two species groups are proposed in Macrolycus s. str. and six in Cerceros. Additionally, twelve Macrolycus species are newly described from China: M. aquilinus, M. baihualingensis, M. bicolor, M. guangxiensis, M. jianfenglingensis, M. kuatunensis, M. lizipingensis, M. parvus, M. phoeniceus, M. rhodoneurus, M. rosaceus and M. sichuanensis. Macrolycus holzschuhi is proposed to be a junior subjective synonym of M. jeanvoinei. The highest diversity of Macrolycus is found in southern China. The species from the main islands of Japan are placed in two species groups: M. excellens is a sister to remaining species of the M. murzini group and the M. flabellatus group is a monophylum of closely related species in a sister position to the M. bicolor group.  相似文献   

8.
The world's argasid tick fauna comprises 183 species in four genera, namely Argas, Carios, Ornithodoros and Otobius in the family Argasidae. The ixodid tick fauna consists of 241 species in the genus Ixodes and 442 species in the genera Amblyomma, Anomalohimalaya, Bothriocroton, Cosmiomma, Dermacentor, Haemaphysalis, Hyalomma, Margaropus, Nosomma, Rhipicentor and Rhipicephalus in the family Ixodidae, with the genus Boophilus becoming a subgenus of the genus Rhipicephalus. The family Nuttalliellidae is represented by the monospecific genus Nuttalliella. The species names of these ticks, based on seven previous complete or partial listings, as well as those of recently described new species, are presented in tabular format. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

9.
10.
Phylogenetic relationships of Genista and related genera (Teline, Chamaespartium, Pterospartum, Echinospartum, Ulex, Stauracanthus and Retama) were assessed by the analysis of sequences of the nrDNA internal transcribed spacer (ITS region), and the cpDNA trnL-trnF intergenic spacer. The tree obtained by combining both sets of data indicates the existence of three lines of diversification within Genista, that correspond to three subgenera: Genista, Phyllobotrys and Spartocarpus, however, each of these lineages encompass also species of the related genera Echinospartum, Teline, Retama, Chamaespartium, Pterospartum, Ulex, Stauracanthus. The molecular data do not support division of these subgenera into taxonomical units at the sectional level; only sections Genista and Spartocarpus are monophyletic groups. The sequences of both regions are also informative at the specific level, grouping morphologically related species (e.g. the G. cinerea aggregate). The molecular data have also helped to clarify the position of taxa whose relationships were not well established (e.g. G. valdes-bermejoi). The relationships of related genera that belong to the Genista lines of diversification have also been investigated. Echinospartum splits into two separate clades matching the separation of two ecological and caryological differentiated groups. Teline also forms two groups, both placed near to Genista subgenus Genista, but that separated from the main core of the group. Retama, morphologically well differentiated from Genista, is close to Genista subgenus Spartocarpus. Chamaespartium and Pterospartum do not form a monophyletic group. Chamaespartium is closer to Genista subgenus Genista, whereas Pterospartum stands close to: 1) Genista subgenus Spartocarpus (particularly, sect. Cephalospartum); and 2) the Ulex-Stauracanthus clade (a terminal derivative of Genista subgenus Spartocarpus). Cases of incongruence (e.g. Echinospartum, Chamaespartium, Teline) between the trees obtained from the two molecular markers, may be indicating hybridisation and/or introgression between different lines of Genisteae.  相似文献   

11.
The S locus and its flanking regions in the genus Prunus (Rosaceae) contain four pollen-expressed F-box genes. These genes contain the S locus F-box genes with low allelic sequence polymorphism genes 1, 2, and 3 (SLFL1, SLFL2, and SLFL3) as well as the putative pollen S gene, named the S haplotype-specific F-box protein gene (SFB). As much less information is available on the function of SLFLs than that of SFB, we analyzed the SLFLs of six S haplotypes of sweet cherry (Prunus avium) in this study. Genomic DNA blot analysis and the isolation of SLFL1 showed that the SLFL1 gene in a functional self-incompatible S 3 haplotype is deleted and only a partial sequence resembling SLFL1 is left in the S 3 locus region, suggesting that SLFL1 by itself is not directly involved in either the GSI reaction or pollen-tube growth. Genomic DNA blot analysis showed that there was no substantial modification or mutation in SLFL2 and SLFL3. A phylogenic analysis of F-box genes in the rosaceous S locus and its border regions showed that Prunus SLFLs were more closely related to maloid S locus F-box brothers than to Prunus SFBs. The functions of SLFLs and the evolution of self-incompatibility in Prunus are discussed based on these results. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. The nucleotide sequence data reported appear in the DDBJ, EMBL, and GenBank Nucleotide Sequence Databases under the accession numbers, AB360339, AB360340, AB360341, and AB360342, for SLFL1-S 1 , SLFL1-S 2 , SLFL1-S 5 , and SLFL1-S 6 , respectively.  相似文献   

12.
13.
该研究利用RACE ( Rapid amplification of cDNA ends)技术从小蓬中成功分离编码金属硫蛋白( Metal-lothionein,MT)的cDNA序列,命名为NeMT2,在GenBank中登录号为KT835290。该基因全长590 bp,开放阅读框为237 bp,编码78个氨基酸,编码的氨基酸序列中含有14个半胱氨酸残基( Cys,C),呈C-C,C-X-C,C-X-X-C排列,集中分布在肽链的N端和C端,基因编码蛋白的分子量为7.6036 kD,等电点为4.71。系统发育分析表明,小蓬金属硫蛋白NeMT2与藜科的海蓬子( AEF01492)和盐穗木( AHI62953)同源性最高,其次是甜菜( XP 010667708.1)。生物信息学分析表明,金属硫蛋白NeMT2无信号肽结构,属于非跨膜亲水性蛋白;疏水性分析表明,NeMT2蛋白的35~45个氨基酸之间有较强的疏水性,其中第41位Asp具最强的疏水性(1.444);结构预测分析该蛋白质二级结构的主要元件是无规则卷曲。通过RT-PCR对NeMT2基因的表达分析发现, NeMT2基因在铜矿区和非铜矿区的小蓬叶片中均有表达,但该基因在铜矿区小蓬叶片的表达量明显高于非铜矿区。将小蓬NeMT2基因定向克隆到植物表达载体pCAMBIA1300的35S 启动子下游,构建该基因的植物超表达载体pCAMBIA1300+NeMT2。该研究结果为进一步研究该基因的功能和小蓬响应重金属胁迫的分子机制提供了一定基础。  相似文献   

14.
Connections among species-abundance (i-m i ), species-frequency (i-F i ), and species-sample size (S n -n) relationships were examined on the basis of the mapping data of a natural forest in Thailand. The spatial distribution of individual trees without any discrimination of species was nearly random. Provided that the spatial distribution of each species was random, thei-m i and thei-F i relationship was reconstructed from each other in terms of the total number of species (S) and the total number of individuals (N) in the data. The number of species (S n ) in a subsample consisting ofn individuals was then obtained from thei-F i relationship. Logarithm ofS n increased with logn and showed a convex curve through the origin. The values of diversity indices based onN andS(orn andS n ) were affected by sample size. These trends were further examined on the basis of 944 data sets of biotic communities and three mathematical models of anS-N relationship. The properties of species-area relation were discussed in the light of these results.  相似文献   

15.
The essential oils (EOs) of two populations of Azorella cryptantha (Clos) Reiche , a native species from San Juan Province, were obtained by hydrodistillation in a Clevenger‐type apparatus and characterized by GC‐FID and GC/MS analyses. The compounds identified amounted to 92.3 and 88.7% of the total oil composition for A. cryptantha from Bauchaceta (Ac‐BAU) and Agua Negra (Ac‐AN), respectively. The EO composition for the two populations was similar, although with differences in the identity and content of the main compounds and also in the identity of minor components. The main compounds of the Ac‐BAU EO were α‐pinene, α‐thujene, sabinene, δ‐cadinene, δ‐cadinol, transβ‐guaiene, and τ‐muurolol, while α‐pinene, α‐thujene, β‐pinene, γ‐cadinene, τ‐cadinol, δ‐cadinene, τ‐muurolol, and a not identified compound were the main constituents of the Ac‐AN EO, which also contained 3.0% of oxygenated monoterpenes. The repellent activity on Triatoma infestans nymphs was 100 and 92% for the Ac‐AN and Ac‐BAU EOs, respectively. Regarding the toxic effects on Ceratitis capitata, the EOs were very active with LD50 values lower than 11 μg/fly. The dermatophytes Microsporum gypseum, Trichophyton rubrum, and T. mentagrophytes and the bacterial strains Escherichia coli LM1, E. coli LM2, and Yersinia enterocolitica PI were more sensitive toward the Ac‐AN EO (MIC 125 μg/ml) than toward the Ac‐BAU EO. This is the first report on the composition of A. cryptantha EO and its anti‐insect and antimicrobial properties.  相似文献   

16.
以疏花卫矛(Euonymus laxiflorus)、丝棉木(E.maackii)和卫矛(E.alatus)3种卫矛属植物为试验材料,测定叶片转色期叶色参数和相关生理生化指标,探讨各项指标的变化规律和内在联系,为优良色叶植物的筛选提供依据。结果表明:(1)转色期,疏花卫矛的明亮度参数L~*和色素参数b~*(黄/蓝)呈上升趋势,色素参数a~*(红/绿)变化不大;丝棉木的L~*和b~*呈先上升后下降的单峰曲线,a~*呈上升趋势;卫矛的L~*和b~*变化不大,a~*呈上升趋势。(2)3种植物的叶绿素含量在转色期呈明显下降趋势;疏花卫矛的花色素苷相对含量、花色素苷/叶绿素的值较为平稳,类胡萝卜素/叶绿素的值呈上升趋势;丝棉木和卫矛的花色素苷相对含量、花色素苷/叶绿素的值均呈上升趋势,类胡萝卜素/叶绿素的值保持平稳。(3)3种植物苯丙氨酸解氨酶(PAL)活性呈下降趋势,查尔酮异构酶(CHI)活性呈先上升后下降的单峰曲线;卫矛的过氧化物酶(POD)和多酚氧化酶(PPO)活性保持平稳,疏花卫矛和丝棉木的POD活性呈上升趋势,疏花卫矛的PPO活性保持平稳,丝棉木的PPO活性呈下降趋势。(4)疏花卫矛和卫矛的可溶性糖和淀粉的质量分数呈先上升后下降的单峰曲线,丝棉木的可溶性糖和淀粉的质量分数呈上升趋势。(5)相关性分析显示,疏花卫矛呈现黄色主要是因为叶绿素的分解,丝棉木和卫矛呈现红色是因为花色素苷的合成,可溶性糖、淀粉、CHI对花色素苷的合成有一定作用,POD对叶片呈现红色有促进作用,PAL和PPO活性对花色素苷的合成无显著影响。  相似文献   

17.
Functions of α‐ and β‐branch carotenoids in whole‐plant acclimation to photo‐oxidative stress were studied in Arabidopsis thaliana wild‐type (wt) and carotenoid mutants, lut ein deficient (lut2, lut5), n on‐p hotochemical q uenching1 (npq1) and s uppressor of z eaxanthin‐l ess1 (szl1) npq1 double mutant. Photo‐oxidative stress was applied by exposing plants to sunflecks. The sunflecks caused reduction of chlorophyll content in all plants, but more severely in those having high α‐ to β‐branch carotenoid composition (α/β‐ratio) (lut5, szl1npq1). While this did not alter carotenoid composition in wt or lut2, which accumulates only β‐branch carotenoids, increased xanthophyll levels were found in the mutants with high α/β‐ratios (lut5, szl1npq1) or without xanthophyll‐cycle operation (npq1, szl1npq1). The PsbS protein content increased in all sunfleck plants but lut2. These changes were accompanied by no change (npq1, szl1npq1) or enhanced capacity (wt, lut5) of NPQ. Leaf mass per area increased in lut2, but decreased in wt and lut5 that showed increased NPQ. The sunflecks decelerated primary root growth in wt and npq1 having normal α/β‐ratios, but suppressed lateral root formation in lut5 and szl1npq1 having high α/β‐ratios. The results highlight the importance of proper regulation of the α‐ and β‐branch carotenoid pathways for whole‐plant acclimation, not only leaf photoprotection, under photo‐oxidative stress.  相似文献   

18.
李江莹  陆添权  杨俊波  田波 《广西植物》2021,41(11):1897-1904
印度血桐与中平树是大戟科血桐属植物,该属植物具有多种药用价值,被广泛应用于民间医学中许多疾病的治疗,这两种植物种子中含有的神经酸也引起了研究者的高度关注。为确定适合印度血桐与中平树的全基因组测序研究策略,该研究采用二代高通量测序技术,结合生物信息学的方法首次测定了印度血桐与中平树的基因组大小、杂合率、重复率等基因组信息并初步分析了两种材料的SSR序列特征。结果表明:(1)印度血桐与中平树的基因组大小分别为986.84和946.23 M。(2)印度血桐与中平树的杂合率分别为0.75%和0.65%,重复序列比例分别为73.02%和71.5%。(3)通过对2种材料基因组序列的SSR特征分析,在印度血桐中共鉴定了4 499 185个SSR,在中平树中共鉴定了4 969 098个SSR。该研究结果为印度血桐与中平树SSR分子标记的筛选、开发以及全基因组深度测序提供了理论指导。  相似文献   

19.
20.
A higher-level phylogenetic classification of the Fungi   总被引:3,自引:3,他引:0  
《Mycological Research》2007,111(5):509-547
A comprehensive phylogenetic classification of the kingdom Fungi is proposed, with reference to recent molecular phylogenetic analyses, and with input from diverse members of the fungal taxonomic community. The classification includes 195 taxa, down to the level of order, of which 16 are described or validated here: Dikarya subkingdom nov.; Chytridiomycota, Neocallimastigomycota phyla nov.; Monoblepharidomycetes, Neocallimastigomycetes class. nov.; Eurotiomycetidae, Lecanoromycetidae, Mycocaliciomycetidae subclass. nov.; Acarosporales, Corticiales, Baeomycetales, Candelariales, Gloeophyllales, Melanosporales, Trechisporales, Umbilicariales ords. nov. The clade containing Ascomycota and Basidiomycota is classified as subkingdom Dikarya, reflecting the putative synapomorphy of dikaryotic hyphae. The most dramatic shifts in the classification relative to previous works concern the groups that have traditionally been included in the Chytridiomycota and Zygomycota. The Chytridiomycota is retained in a restricted sense, with Blastocladiomycota and Neocallimastigomycota representing segregate phyla of flagellated Fungi. Taxa traditionally placed in Zygomycota are distributed among Glomeromycota and several subphyla incertae sedis, including Mucoromycotina, Entomophthoromycotina, Kickxellomycotina, and Zoopagomycotina. Microsporidia are included in the Fungi, but no further subdivision of the group is proposed. Several genera of ‘basal’ Fungi of uncertain position are not placed in any higher taxa, including Basidiobolus, Caulochytrium, Olpidium, and Rozella.  相似文献   

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