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1.
The variability level of the ISSR (inter-simple sequences repeat) primer (GACA)4 was examined in the three Lepidoptera families Pyralidae, Sphingidae and Pieridae. Our study shows that the tetra-repeat (GACA)n is evidently present in sufficient numbers in these butterflies to provide informative DNA fingerprints. The variability is mostly rather high, but within a comparable range to other ISSR studies. Although less polymorphisms may be encountered in some butterfly families, this study indicates that high variability of this marker may be a common characteristic of Lepidoptera genomes. An appeal for a minimal level of standardization of ISSR-PCR data analysis is formulated to enable an exact comparison between the groups of organisms studied with this fingerprint technique.  相似文献   

2.
Morphological and molecular analysis of 15 Philippine populations of eggplant fruit and shoot borer (EFSB), Leucinodes orbonalis Guenée were conducted to determine if these populations are constituted singly by L. orbonalis or by different species and to assess the level of variability among them. Morphometric analysis of five genital traits of 850 male adult EFSB from field populations and analysis of the COI gene sequence of 879 F1 EFSB larvae from 15 main eggplant-producing provinces identified all individuals as belonging to L. orbonalis. Principal Component Analysis of five morphometric genital characters revealed high similarity among the EFSB populations regardless of geographic location. Thirteen (13) sequence variants (haplotypes) were identified, with one haplotype predominant and widespread throughout the country. The remaining haplotypes occurred rarely and differed from the widespread haplotype by one mutation. Overall, the EFSB populations from Philippines exhibited low nucleotide and haplotype diversity, indicating low genetic diversity. Topologies from a maximum likelihood tree indicate all thirteen haplotypes cluster in a single clade with EFSB populations from India and other South-East Asian countries. Further analysis with the Generalized Mixed Yule Coalescent (GMYC) method classified the different haplotypes into a single GMYC entity. Combined with morphometric analysis, differences between haplotypes are not suggestive of any subspecies. Negative values of Tajima's D and Fu's Fs tests combined with the phylogenetic analysis and overall low genetic diversity of Philippine populations support the hypothesis that EFSB is not endemic but introduced to the Philippines.  相似文献   

3.
The last instar larva and pupa of Melipotis cellaris (Guenée) are described and illustrated, based on specimens collected in northern Chile, associated with Acacia macracantha (Fabaceae).  相似文献   

4.
This study provides comprehensive documentation of silk production in the pest moth Helicoverpa armigera from gland secretion to extrusion of silk thread. The structure of the silk glands, accessory structures and extrusion apparatus are reported. The general schema of the paired silk glands follows that found for Lepidoptera. Morphology of the duct, silk press, muscle attachments and spigot are presented as a three-dimensional reconstruction and the cuticular crescent-shaped profile of the silk press is demonstrated in both open and closed forms with attendant muscle blocks, allowing advances in our knowledge of how the silk press functions to regulate the extrusion of silk. Growth of the spigot across instars is documented showing a distinctive developmental pattern for this extrusion device. Its shape and structure are related to use and load-bearing activity.  相似文献   

5.
二点委夜蛾Athetis lepigone 是2005年首次在河北省发现危害夏玉米苗的新害虫,2011年7月在河北、河南、山东、山西、安徽和江苏6省47市夏玉米苗期大面积暴发成灾,严重威胁玉米生产.为了从种群水平探讨该虫暴发成灾的机制,我们通过分析线粒体细胞色素氧化酶亚基Ⅰ (mtCO Ⅰ)基因序列来研究不同地区二点委夜蛾种群的进化关系.本研究采集了河北、河南、山东和山西等地的19个不同地理种群样本,用同源序列比对的方法分析样本mtCO Ⅰ基因片段,利用DnaSP 5.0软件和Arlequin 3.5软件对不同地理种群间的mtCO Ⅰ单倍型多样性分析和Tajima's D中性检测,建立了单倍型邻接(N-J)系统发育进化树和单倍型网络图.结果表明,在203头个体的658 bp mtCO Ⅰ基因片段中,得到17种单倍型和18个变异位点,河北省的二点委夜蛾的单倍型多态性最丰富,而河南、山东和山西3省采集的二点委夜蛾样品其单倍型均有与河北种群单倍型一致的类型.二点委夜蛾不同地理种群间基因流水平较高,种群间没有明显的遗传分化,并且在较近的历史时期未经历明显的种群扩张.  相似文献   

6.
Plant chemistry can strongly influence interactions between herbivores and their natural enemies, either by providing volatile compounds that serve as foraging cues for parasitoids or predators, or by affecting the quality of herbivores as hosts or prey. Through these effects plants may influence parasitoid population genetic structure. We tested for a possible specialization on specific crop plants in Chelonus insularis and Campoletis sonorensis, two primary parasitoids of the fall armyworm, Spodoptera frugiperda. Throughout Mexico, S. frugiperda larvae were collected from their main host plants, maize and sorghum and parasitoids that emerged from the larvae were used for subsequent comparison by molecular analysis. Genetic variation at eight and 11 microsatellites were respectively assayed for C. insularis and C. sonorensis to examine isolation by distance, host plant and regional effects. Kinship analyses were also performed to assess female migration among host‐plants. The analyses showed considerable within population variation and revealed a significant regional effect. No effect of host plant on population structure of either of the two parasitoid species was found. Isolation by distance was observed at the individual level, but not at the population level. Kinship analyses revealed significantly more genetically related—or kin—individuals on the same plant species than on different plant species, suggesting that locally, mothers preferentially stay on the same plant species. Although the standard population genetics parameters showed no effect of plant species on population structure, the kinship analyses revealed that mothers exhibit plant species fidelity, which may speed up divergence if adaptation were to occur.  相似文献   

7.
Responses of adult Indianmeal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) to light alone and to a combination of attractant(s) and green/UV lights were studied. When P. interpunctella adults were given a choice between dark areas and areas illuminated with UV, green, or white light, they rested preferentially on surfaces in the illuminated areas. UV light elicited the strongest of the positive phototactic responses. Light traps were not as effective as traps baited with pheromones or food lures in capturing adult moths, and combining green or UV light with these attractants did not significantly increase the trap catches. Gravid females required a period of darkness to realize maximum oviposition, and illumination above 8 lx during the scotophase of a 24-hr light–dark cycle inhibited oviposition.  相似文献   

8.
Surveys for Stenoma catenifer Walsingham, the avocado seed moth, and its associated larval parasitoids were conducted in the Departments of Junín, Huánuco, Cusco, and Madre de Dios in Perú. Fruit infestation levels in some areas ranged from 0 to 58%, and parasitism of S. catenifer larvae in Junín and Huánuco was 23%. Five species of hymenopteran parasitoid in two families, Braconidae (Apanteles sp., Hypomicrogaster sp., and Chelonus sp.) and Ichneumonidae (Pristeromerus sp. and Xiphosomella sp.), were reared from larvae, and one species of tachinid fly (Chrysodoria sp.) emerged from pupae. The dominant larval parasitoid, a gregarious Apanteles sp., accounted for 55% of parasitized hosts. Branch and twig tunneling by S. catenifer larvae in a commercial Hass avocado orchard was observed in Cusco. The field attractiveness of the sex pheromone of S. catenifer was demonstrated with 73% of monitoring traps deployed in three departments (Junín, Huánuco, and Cusco) catching male moths. Approximately 55% of avocado fruit sourced from the Province of Chanchamayo (Junin) and purchased at the Mercado Modelo de Frutas in La Victoria, in central Lima were infested with larvae of S. catenifer. Infested avocado fruit sold at this market could represent a potential incursion threat to coastal Hass avocado production regions in Perú that are reportedly free of this pest.  相似文献   

9.
Basic research will spur development of genetic tests that are capable of presymptomatic prediction of disease, disability, and premature death in presently asymptomatic individuals. Concerns have been expressed about potential harms related to the use of genetic test results, especially loss of confidentiality, eugenics, and discrimination. Existing laws and administrative policies may not be sufficient to assure that genetic information is used fairly. To provide factual information and conceptual principles upon which sound social policy can be based, the Human Genome Initiative established an Ethical, Legal, and Social Issues Program. Among the first areas to be identified as a priority for study was insurance. This paper provides a review of life, health, and disability insurance systems, including basic principles, risk classification, and market and regulatory issues, and examines the potential impact of genetic information on the insurance industry.  相似文献   

10.
《Journal of Asia》2022,25(2):101886
The double line moth, Mythimna turca (Linnaeus, 1761) (Lepidoptera: Noctuidae), is an important widely distributed insect species. Studies on the moth in European countries have focused on population monitoring and in China on taxonomy of Mythimna and distribution surveys of M. turca. However, whether M. turca is a migratory insect is unknown. Here, migration of the moth population was monitored using a searchlight trap from 2004 to 2020 on Beihuang island, Northern China, providing direct evidence that M. turca migrates across the Bohai Strait seasonally, in late May to early September. Population dynamics, ovarian development, wind direction and possible migration trajectories were also analyzed. Most moths migrated in June and at the end of August and the beginning of September, and a few migrated in May, July and October. The average duration of this windborne migratory period of M. turca was 93 d. Migratory trajectories demonstrated that M. turca mainly moved northward in spells of southerly winds from June to August and moved southward in spells of northerly winds during September. This new key information about the ecology of M. turca population will aid the formulation of M. turca management strategies.  相似文献   

11.
Impact of some insecticides and their mixtures (Emamectin benzoate, Imidaclopride, Chlorfenapyr, Indoxacarb, Profenofos, Pyridalyl, Methomyl and Teflubenzuron) were evaluated against the tomato borers, Tuta absoluta (Meyrick) and Helicoverpa armigera (Hübner) population in tomato crop at Upper Egypt. Results of LC50 values indicated that Emamectin benzoate was the most toxic compound (LC50 0.461%) against T. absoluta, larvae. The carbamate insecticide, Methomyl, followed this descending order, showing almost similar toxicity, while Teflubenzuron and Chlorfenapyr were less effective (LC50 1.054 and 3.165%, respectively). Pyridalyl was found to be the most effective insecticide against larval stage of H. armigera. (LC50 0.513%). The corresponding toxicities of the other tested insecticides, arranged according to their LC50 values in descending order were as follow: Methomyl, Emamectin benzoate, Profenofos, Imidaclopride, Teflubenzuron, Indoxacarb and Chlorfenapyr. Their LC50 values were ranged between (0.513 and 0.872%). While, their toxicity indexes were ranged between (92.432 and 58.830%, respectively). On the other hand, there were no differences occurred among the treatments. Mean of percent infestation was decreased six weeks after six sprayings, and the per cent reduction in infestation was 79.73, 80.22, 78.41, 80.88, 80.50, 78.30, 79.64 and 78.25% using Emamectin benzoate, Methomyl, Imidaclopride, Pyridalyl, Profenofos, Indoxacarb, Teflubenzuron and Chlorfenapyr, respectively. The efficiency of the tested insecticides was increased with increasing the number of sprays from two to six causing reduction in insect borer infestation ranged between 68.02 and 80.88%, respectively. Generally, the tested insecticides and their mixtures achieved a considerable reduction in T. absoluta and H. armigera population.  相似文献   

12.
Specimens taxonomically treated in the Fauna Hawaiiensis were associated by cluster analysis, thereby reconstructing assemblages of Hawaiian carabid beetle species (Coleoptera: Carabidae) observed during the late 19th century. Associations among specimens representing 193 species permit concise hypotheses of habitat preferences for many of the 32 carabid species collected during the early period of European scientific exploration (1872–1902), but not observed since. These associations are consistent with data derived from contemporary biological surveys of Hawai'i. Absence of entire clusters of associated species from recent collections suggests actions of common agents leading to extinction or extreme population reduction. The candidate list of threatened and endangered species of the US. Fish and Wildlife Service established prior to 1994 included one Hawaiian carabid species missing since 1902, versus eight other species collected at various times over the past century. Improvements in knowledge of carabid beetle species’ spatial distribution and temporal persistence derived from recent field survey and taxonomic research demonstrate that the types of criteria used to construct that list must be rejected. Future consideration of official conservation status for any Hawaiian carabid beetle species must take into account the status of ecologically associated species, and the limited likelihood that individuals of all extant species can be consistently observed in nature due to their natural relative rarity or their secretive habits within restricted geographic and ecological distributions. Historical specimen associations serve as the best guides for continuing efforts to monitor known faunal members and to rediscover long‐missing species. These associations also serve to link information concerning individual species with particular habitats.  相似文献   

13.
The life history of Spodoptera exigua was studied under laboratory conditions at temperature of 25°C ± 1°C, relative humidity (RH) of 60% ± 5% and a photoperiod of 16:8 h (Light:Dark) on nine soybean (Glycine max L.) cultivars: 032, 033, Hill, M4, M7, M9, M11, TMS and Zan. Larval and pupal development times were longest on M7 cultivar (14.09 ± 0.078 and 7.78 ± 0.090 days) and shortest on 033 cultivar (11.98 ± 0.054 and 7.033 ± 0.090 days). The longest and shortest female and male longevities were observed on Hill and Zan cultivars, respectively. The results showed that the whole life span varied from 32.80 ± 0.89 to 37 ± 0.98 days for females and from 33.3 ± 0.66 to 38.74 ± 0.95 days for males. The highest daily fecundity was obtained on M9 (102. 38 eggs), and the lowest on Hill (75.87 eggs). Mean total fecundity per female during adult life was highest on 033 (1156.20 eggs) and lowest on M7 cultivars (841.68 eggs). Clustering analysis of the biological parameters of S. exigua confirmed that 033 and Hill cultivars were the susceptible and the resistant cultivars, respectively.  相似文献   

14.
In the spring of 1985, a species of chaicid wasps was reared from the pupae of fall webworm, Hyphantria cunea (Drury) (Lepidoptera:Arctiidae) during myinvestigation on the parasitoids of this introduced harmful insect pest inShaanxi Province, China. With high parasitic ratio (over 80 percent) and a largenumber of individuals (over 200 were usually reared from a single pupa of the  相似文献   

15.
The European endemic Erebia oeme (Hübner [1804]) (Lepidoptera: Nymphalidae: Satyrinae) is discovered in the Carpathian Chain, from where it was considered to be absent. The single population found is situated in the southern part of the Romanian Carpathians (Retezat Mountains), where it flies sympatrically and synchronically with Erebia medusa ([Denis & Schiffermüller] 1775). The similar external morphology of these two species probably caused E. oeme to be overlooked in the Carpathians, leading to an unexpected information gap in the otherwise thoroughly studied European continent. The morphology of the Romanian specimens is compared to populations from the rest of the species’ range and to E. medusa. In addition, we tested DNA barcoding as a method to discriminate between these species and confirmed that it represents an effective identification tool for the taxa involved. The habitat of E. oeme, adults of both sexes and their genitalia are illustrated in comparison with E. medusa. Based on the study of several collections, we show that E. oeme is likely to be extremely local in the Carpathians and provide arguments to consider the species as vulnerable in Romania.  相似文献   

16.
Summary Twelve cases of lissencephaly are reported. A high resolution chromosome study was performed on each in order to detect small chromosomal anomalies, undetectable with routine techniques. Only one case was shown to have an unbalanced karyotype with a microdeletion of the short arm of chromosome 17(del 17p). This child also had symptoms of the Miller-Dieker syndrome, consisting of lissencephaly, characteristic facies, pre- and post-natal growth retardation and other birth defects. As proposed by Dobyns, it seems justifiable to classify lissencephalies into four different groups, according to other clinical manifestations and results of chromosome studies.  相似文献   

17.
We present a range-wide synthesis of our own research and related work on the complex postglacial history of Abies alba Mill. It is based on macroremains, fossil pollen records as well as on different genetic markers. The geographic distribution of genetic lineages and allele frequencies together with the fossil records confirm multiple refugia with at least three of them being sources for the Holocene range expansion into Central Europe, representing so-called effective refugia. One is located in the northern Apennines. A long-term refugium in the southern Balkans contributes to northward expansion with a branch along the Carpathians in the East and the Dinaric Alps in the West. Furthermore, new allozyme data indicate a third effective refugium in the northern or western Balkans, respectively. Using different genetic marker categories the differentiation of A. alba populations could be attributed to different time scales. A separation of maternal lineages took place in previous glacial cycles of the Quaternary, while a second pattern of genetic differentiation is the result of isolation processes during the last glaciation and subsequent gene flow after range expansion. Suture and introgression zones of refugial gene pools were clearly recognised. The patterns of genetic variation and genetic diversity spanning between rear and leading edges of the present range are discussed for evolutionary implications and conservation strategies.  相似文献   

18.
Propagule banks are assumed to be able to store considerable genetic variability. Bryophyte populations are expected to rely more heavily on stored propagules than those of seed plants due to the vulnerability of the haploid gametophyte. This reliance has important implications for the genetic structure and evolutionary potential of surface populations. A liverwort, Mannia fragrans, was used to test whether the bryophyte diaspore bank functions as a "genetic memory." If a diaspore bank is capable of conserving genetic variability over generations, the levels of genetic diversity in the soil are expected to be similar or higher than at the surface. Surface and diaspore bank constituents of two populations of M. fragrans were investigated. Genetic structure and diversity measured as unbiased heterozygosity were analyzed using three ISSR markers. Similar genetic diversities were found in the soil (H(s) = 0.067) and at the surface (H(s)= 0.082). However, more haplotypes and specific haplotype lineages were present in soil samples. The results suggest that the bryophyte diaspore bank has an important role in accumulating genetic variability over generations and seasons. It is postulated that the role of the diaspore bank as a "genetic memory" is especially important in species of temporarily available habitats that have long-lived spores and genetically variable populations.  相似文献   

19.
20.
Summary The physicochemical properties of -turns suggest their biological importance prior to the formation of the genetic code. These properties include ones potentially affecting the preference for eitherl- ord-amino acids. The abundance of certain amino acids in -turns is correlated with their assignment to a small, well-defined part of the genetic code and with their role as metabolic precursors for other amino acids. It is proposed that in the prebiotic environment, -turns became objects of selection that influenced the evolution of the genetic code and biosynthetic pathways for amino acids.  相似文献   

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