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In: Nematology
In: Nematology
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In American Christian Programmed Quaker Ecclesiology, Derek Brown argues that American Christian Programmed Quakerism has inherited a practical and pragmatic ecclesiology at the expense of an ontological understanding of the church. Inspired by the work of Gerben Heitink, Brown proposes a normative, deductive, ontological ecclesiology based on the biblical concept of koinonia, which would act as a 'foundational' model for future confessional, empirical, and practical efforts. To help form the proposed ecclesiology, Brown explores the ecclesiological views of George Fox and Robert Barclay, the adoption of the pastoral system, and the emergence of the Evangelical Friends Church. The ecclesiological writings of Miroslav Volf, Wolfhart Pannenberg, Hans Küng, Jennifer Buck, and C. Wess Daniels are also surveyed.
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In American Christian Programmed Quaker Ecclesiology: A Foundational Model for Future Empirical and Confessional Approaches, Derek Brown argues that American Christian Programmed Quakerism (ACPQ – a non-organizational label designating programmed Christian Friends churches in America) has inherited a practical and pragmatic ecclesiology at the expense of an ontological understanding of the church. Inspired by the work of Gerben Heitink, Brown proposes a normative, deductive, ontological ecclesiology based on the biblical concept of koinonia, which would act as a ‘foundational’ model for future confessional, empirical, and practical efforts. To help form the proposed ecclesiology, Brown explores the ecclesiological views of George Fox and Robert Barclay, the adoption of the pastoral system, and the emergence of the Evangelical Friends Church. The ecclesiological writings of Miroslav Volf, Wolfhart Pannenberg, Hans Küng, Jennifer Buck, and C. Wess Daniels are also surveyed.

In: American Christian Programmed Quaker Ecclesiology

Abstract

Different combinations of strains of pea early-browning and tobacco rattle Tobraviruses with selected Paratrichodorus and Trichodorus species were examined to identify if differences occurred in the location of virus particle retention within the nematodes. The study revealed that the sites of virus particle retention differed between the individual Tobravirus-trichodorid combinations. No differences were found in the sites of virus retention in nematodes that had been allowed to acquire, but not to transmit, virus compared with nematodes that had been allowed to acquire and subsequently transmit the virus. Virus particles of several strains of Tobraviruses were acquired and retained by trichodorids that are not natural vectors of the particular virus. In these instances the particles were retained within the pharyngeal tract at locations from where when released they are unable to be transferred anteriorly along the pharyngeal tract into plant cells, but rather they can move only posteriorly into the nematode intestine.

In: Nematology

Abstract

The plant-parasitic nematode Paratrichodorus anemones efficiently transmits tobacco rattle virus that causes substantial economic damage to vegetable and ornamental flower-bulb crops. The nematode acquires and transmits virus particles when feeding on plant roots, but previous studies on feeding by trichodorid nematodes suggested that the nematodes destroyed the cells upon which they fed. For successful establishment of virus infection in a plant, virus particles would have to be introduced by the nematode into root cells that would remain fully functional. Consequently, the efficient transmission of the genus Tobravirus by trichodorids could not occur where the majority of attacked root cells become irreversibly damaged and, therefore, unsuitable for establishment of virus infection. Live specimens of P. anemones feeding on Nicotiana tabacum seedlings growing in agar were examined in real time using videoenhanced interference light microscopy to determine how trichodorids acquire and transmit Tobravirus particles. The feeding cycle of P. anemones had four distinct phases: i) root exploration, ii) cell exploration, iii) cell sampling, and iv) cell feeding, followed by a quiescent period. Preceding the initiation of phase iv) an average of four cells, which had been perforated by the nematode onchiostyle, were immediately abandoned and thus remained fully functional. Also, during this phase, about 5% of the perforated cells remained alive and fully functional, providing a suitable environment for the establishment of virus infection. Each feed on a single cell was similar to that previously observed with Trichodorus similis, being in four phases, i.e., cell wall perforation, salivation, ingestion and withdrawal.

In: Nematology

Abstract

Virus-vector plant-parasitic Paratrichodorus and Trichodorus nematodes acquire Tobravirus particles whilst ingesting root cell sap from virus-infected plants and these particles are specifically retained by being adsorbed on to the cuticle lining the wall of the nematode pharyngeal lumen. The feeding apparatus and pharyngeal ultrastructure of four trichodorid virus-vector species were examined to identify the occurrence of any structural characters that could account for particle retention at specific sites in this region. Similarities between Paratrichodorus and Trichodorus species are reported for the first time and new evidence is provided on the position of all gland sinuses and outlets. The occurrence of an inner spear in adult specimens is discussed.

In: Nematology

Abstract

A description is provided of Longidorus dalmassoi sp. n., a bisexual species associated with grasses in France. The species is characterised by a body length of 6.9-7.8 mm, slightly expanded and anteriorly flattened head region, symmetrically bilobed amphidial pouches, long odontostyle (152-163 mu m), spear guiding system with compensation sacks, conoid tail (39-52.5 mu m) with narrow, rounded terminus, males with short spicules (50-51 mu m) and a row of 15 or 16 supplements. Longidorus dalmassoi sp. n. (Nematoda: Longidoridae) provenant de France - Description est donnee de Longidorus dalmassoi sp. n., espece bisexuee associee a une vegetation herbacee, en France. Cette espece est caracterisee par une longueur du corps de 6,9-7,8 mm, une extremite anterieure legerement elargie et aplatie a l'avant, des poches amphidiennes symetriques et bilobees, un odontostyle long (152-163 mu m), un systeme de guidage du stylet comportant des sacs de compensation, une queue conoide (39-52,5 mu m) a extremite etroite et arrondie, des males a spicules courts (20-51 mu m) et pourvus d'une rangee de 15 ou 16 supplements.

In: Nematology

Abstract

A short insert genomic library for Xiphinema index, the natural vector of Grapevine Fanleaf Virus, was constructed from degenerate oligonucleotide primed PCR (DOP-PCR) products. The genomic library was screened for (CA)n microsatellites. Screening of 6200 colonies and comparison of the sequencing results revealed seven (CA)n containing microsatellites, coded here as XIMSL1, XIMSL2, XIMSL3, XIMSL4, XIMSL5, XIMSL6 and XIMSS1. XIMSL prefixed microsatellites were followed by the motif of the same long interspersed element. Microsatellite XIMSS1 has some similarity to the short interspersed element. Except for XIMSL1, all microsatellites were proven to be effective diagnostic tools at species level. Genetic diversity between and within populations was also evaluated for each microsatellite.

In: Nematology