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81.
ALEXANDER RIEDEL TOMY DOS SANTOS ROLO ANGELICA CECILIA THOMAS VAN DE KAMP 《Zoological Journal of the Linnean Society》2012,165(4):773-794
Two genera of extinct weevils, Sayrevilleus Gratshev & Zherikhin from Cretaceous New Jersey amber and Baltocar Kuschel from Eocene Baltic amber, are recognized as close relatives based on similarities revealed by the use of synchrotron tomography and the availability of new amber inclusions. The subfamily Sayrevilleinae Legalov stat. nov. is characterized by possessing mandibles with an external cutting edge and an inner blunt edge. The subfamily is placed in the family Attelabidae (s.l.), although some characters also suggest a possible relationship with the ‘higher weevils’ comprising Caridae, Brentidae, and Curculionidae. Sayrevilleus is transferred from the tribe Auletini of Rhynchitinae to Sayrevilleinae, and Sayrevilleus grimaldii Gratshev & Zherikhin is redescribed. Baltocar Kuschel is transferred from Caridae to Sayrevilleinae and revised, its type species, Baltocar succinicus (Voss), is redescribed and three new species, Baltocar groehni Riedel sp. nov. , Baltocar hoffeinsorum Riedel sp. nov. , and Baltocar subnudus Riedel sp. nov. are described based on eight well‐preserved inclusions. The genera Orapauletes Legalov and Zherichiniletes Legalov previously assigned to Sayrevilleini are regarded as Curculionoidea incertae sedis. The Sayrevilleinae were distributed over areas of North America and Europe at least since the Late Cretaceous (c. 90 Mya) and were probably relatively diverse until the Eocene (c. 44 Mya). It is speculated that they became extinct through competition with Curculionidae, which used a similar oviposition strategy. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 773–794. 相似文献
82.
Insecticide susceptibility status in Mexican populations of Stegomyia aegypti (= Aedes aegypti): a nationwide assessment 下载免费PDF全文
P. A. KURI‐MORALES F. CORREA‐MORALES C. GONZÁLEZ‐ACOSTA M. MORENO‐GARCIA R. SANTOS‐LUNA S. ROMÁN‐PÉREZ F. SALAZAR‐PENAGOS M. LOMBERA‐GONZÁLEZ G. SÁNCHEZ‐TEJEDA J. F. GONZÁLEZ‐ROLDÁN 《Medical and veterinary entomology》2018,32(2):162-174
In Mexico, mosquito vector‐borne diseases are of public health concern as a result of their impact on human morbidity and mortality. The use of insecticides against adult mosquitoes is one of the most common ways of controlling mosquito population densities. However, the use of these compounds has resulted in the development of insecticide resistance. The aim of this study was to estimate susceptibility to six pyrethroids, two carbamates and two organophosphates in Mexican populations of Stegomyia aegypti (Linnaeus, 1762) (= Aedes aegypti) (Diptera: Culicidae) mosquitoes. Bottle insecticide susceptibility tests, with 1 h exposure, were performed on adult mosquitoes from 75 localities across 28 states. At 30 min of exposure, the proportion of fallen mosquitoes was recorded. After 60 min of exposure, mosquitoes were recovered in non‐treated containers and mortality was determined at 24 h after the set‐up of the experiment. In general, the carbamate insecticides represented the most effective group in terms of the proportion of mosquitoes fallen at 30 min (72–100%) and 24‐h mortality (97–100%). High and widespread resistance to pyrethroids Types I and II and, to a lesser extent, to organophosphates was observed. Insecticide susceptibility among and within states was highly variable. 相似文献
83.
This study describes the somatic embryogenesis of Theobromacacao L. with a scanning electron microscope. It revealed earlydevelopmental stages as globular and incipient heart-shaped.Morphological abnormalities, such as the occurrence of threeand four cotyledons and round or long forms of embryoids witha long and thin or short and thick stalk-like structure whichseems to equate to a suspensor, were also observed. A suspensorwas found in some embryoids. cacao, Theobroma cacao, embryoids, somatic embryogenesis, SEM 相似文献
84.
S. ITOW JANKEVICIUS IMAWS L. DE ALMEIDA J. VITOR JANKEVICIUS MANZÉLIO CAVAZZANA JR. MARCIA ATTIAS WANDERLEY DE SOUZA 《The Journal of eukaryotic microbiology》1993,40(5):576-581
ABSTRACT. Trypanosomatids isolated from corn seeds and from digestive tract and salivary glands of Leptoglossus zonatus (Hemiptera, Coreidae) were obtained in pure cultures. In experimental transmission, the flagellates present in naturally infected insects were able to infect laboratory-raised corn. A simplified liquid culture medium was established that increased parasite yield three- to five-fold. Cultured and cloned parasites, and forms found in insects and corn as well, were studied by light and electron microscopy. A remarkable finding was the observation that the cultured strain 163M bears a surface coat similar to that observed in naturally occurring African trypanosomes. but not observed in trypanosomes in vitro. Based on the biochemical characteristics of the arknine-ornithine cycle and on the presence of this cell coat, we propose that the strain 163M is a new species and name it Herpetomonas macgheei n. sp. 相似文献
85.
MEENAKSHI VENUGOPAL JAMES M. JAMISON JACQUES GILLOTEAUX JOHN A. KOCH MARCIA SUMMERS JASON HOKE COLLEEN SOWICK JACK L. SUMMERS 《Cell biology international》1996,20(12):787-797
Vitamins C, K3(VC, VK3) and a VC/VK3combination with a VC:VK3ratio of 100:1 were assayed for their antitumour activity against two human prostatic carcinoma cell lines. Co-administration of the vitamins enhanced the antitumour activity 5- to 20-fold even with a 1 h exposure time. While exogenous catalase destroyed the antitumour activity, hydrogen peroxide-induced lipid peroxidation was negligible. Analysis of cellular ATP and thiol levels as well as DNA and protein synthesis revealed: a transient increase in ATP production, a decrease in DNA synthesis, an increase in protein synthesis and a decrease in thiol levels. These results suggested that the increased cytotoxicity of the vitamin combination was due to redox cycling and increased oxidative stress. 相似文献
86.
Abstract Carex misera is a rare sedge, endemic to rocky outcrops and mountain summits within the southern Appalachian Mountains from northern Georgia to northern North Carolina. We assessed allozyme diversity for 406 individuals from nine populations over most of the geographic range. Twenty-seven putative loci were assayed and eight (30%) were found to be polymorphic. Nei's gene diversity statistics ( H T =0.043, H S =0.019, G ST =0.551) indicated low levels of variation but relatively highly differentiated populations, suggesting little gene flow. Significant deviations from genotypic expectations under Hardy-Weinberg equilibrium, high positive fixation indices, and the existence of small genetic neighborhoods within populations suggest that at least some inbreeding occurs. Cluster analysis of Nei's genetic identity statistics and principal component analysis of allele frequency data showed high similarity among the six southern populations with the two northern populations more differentiated from them and from each other. These results suggest that preservation of the northern populations is necessary to conserve the already low levels of genetic diversity within the species. 相似文献
87.
E. SANTOS M. MATOS P. SILVA A. M. FIGUEIRAS C. BENITO O. PINTO-CARNIDE 《Journal of genetics》2016,95(2):273-281
The objective of this study was to quantify the molecular diversity and to determine the genetic relationships among Secale spp. and among cultivars of Secale cereale using RAPDs, ISSRs and sequence analysis of six exons of ScMATE1 gene. Thirteen ryes (cultivated and wild) were genotyped using 21 RAPD and 16 ISSR primers. A total of 435 markers (242 RAPDs and 193 ISSRs) were obtained, with 293 being polymorphic (146 RAPDs and 147 ISSRs). Two RAPD and nine ISSR primers generated more than 80% of polymorphism. The ISSR markers were more polymorphic and informative than RAPDs. Further, 69% of the ISSR primers selected achieved at least 70% of DNA polymorphism. The study of six exons of the ScMATE1 gene also demonstrated a high genetic variability that subsists in Secale genus. One difference observed in exon 1 sequences from S. vavilovii seems to be correlated with Al sensitivity in this species. The genetic relationships obtained using RAPDs, ISSRs and exons of ScMATE1 gene were similar. S. ancestrale, S. kuprijanovii and S. cereale were grouped in the same cluster and S. segetale was in another cluster. S. vavilovii showed evidences of not being clearly an isolate species and having great intraspecific differences. 相似文献
88.
CHARLES MORPHY D. SANTOS DALTON S. AMORIM BRUNA KLASSA DIEGO A. FACHIN SILVIO S. NIHEI CLAUDIO J. B. DE CARVALHO RAFAELA L. FALASCHI CÁTIA A. MELLO‐PATIU MÁRCIA S. COURI SARAH S. OLIVEIRA VERA C. SILVA GUILHERME C. RIBEIRO RENATO S. CAPELLARI CARLOS JOSÉ E. LAMAS 《Systematic Entomology》2016,41(3):511-515
89.
15N-Nuclear Magnetic Resonance (NMR) was used to study nitrogenassimilation in apices of maize roots in vivo, perfused eitherwith 15NO 相似文献
90.
Under greenhouse conditions, Epidendrum nocturnum Jacq. plantsproduce fruits by both self-fertilization and cleistogamy. Althoughadapted to these reproductive processes the species respondalso to cross-pollination. Seeds without embryos and with oneembryo are usual but occasionally seeds with two, three or fourembryos are produced. Multiple embryos are formed by polyembryonyand apomixis. Epidendrum nocturnum, self-pollination, cleistogamy, apomixis, polyembryony, supernumerary embryos 相似文献