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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Phylogenetic and population genetic studies on some insect and plant associated nematodes

Saeb, Amr T. M. January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 150-163).
2

Feeding preference of pine sawyer beetle (Monochamus carolinensis) on Pinaceae and use of virtual plant walk maps as a tool for teaching plant identification courses

Wilson, Matthew Stephen January 1900 (has links)
Doctor of Philosophy / Department of Horticulture, Forestry, and Recreation Resources / Jason Griffin / Feeding preference experiments with the pine sawyer beetle (Monochamus carolinensis Olivier) were conducted using eleven taxa of Pinaceae. One newly emerged adult beetle (≤ 24 hours) was placed into each feeding arena (n = 124) containing three or four shoots of current season's growth from different tree species (one shoot per species) for choice experiments. Beetles were allowed to feed for 48 (2011) or 72 (2012-2014) hours, at which point shoots were removed and data collected on feeding occurrence and percent feeding area. Augmented design analyses of feeding occurrence and percent feeding area of the eleven taxa did not indicate significant evidence for feeding preferences of the pine sawyer beetle on most taxa except for a higher preference for both scots (Pinus sylvestris L.) and eastern white (P. strobus L.) pines compared to deodar cedar [Cedrus deodara (Roxb. ex D. Don) G. Don]. The feeding preference experiments suggest that pine sawyer beetle may feed on a wide-range of Pinaceae taxa. Virtual plant walk maps were developed using a web-application for two semesters of an ornamental plant identification course (n = 87). The maps allowed students to revisit plants and information covered in lecture and laboratory sections at their own convenience, using either a computer or mobile device. Survey results indicated 63% of the students used the virtual plant walk maps as a study resource. Students mainly used the maps to study the most current plant list. Most students who used the virtual maps did so to review the plants online. When asked to rate usefulness of the maps on a scale from slightly useful (1) to very useful (3), 43% of students indicated that the virtual maps study tool was very useful, 25% indicated the maps were useful, and 8% indicated that the maps were slightly useful. A significant dependence between student use frequency and student usefulness ratings of virtual plant walk maps was observed. As students’ use of the virtual maps increased, they perceived the maps to be more useful to their studies in preparing for identification quizzes. No differences between plant identification quiz scores were observed between students who used and did not use the virtual plant walk maps or between learning styles. Our survey indicated students used the virtual plant walk maps as a resource and perceived the maps as a useful tool in preparation for identification quizzes.
3

Hlístice přenášené kozlíčkem sosnovým (Monochamus galloprovincialis (Olivier, 1795)) (Coleoptera: Cerambycidae)

Rolincová, Petra January 2018 (has links)
The longhorn beetle Monochamus galloprovincialis (Oliver, 1795)) is a secondary wood-boring pest of pine trees. It is also an important vector of the pine wood nematode (Bursaphelenchus xylophilus (Steiner & Buhrer, 1934)), a quarantine organism that has caused large damage to pine forests in Asia and Portugal. Therefore, it is desirable to monitore the vector and its associated organisms. The aim of this work was to gain insight into the nematodes transmitted by Monochamus galloprovincialis and to evaluate their biological interactions based on literary sources. The trapping of the longhorn beetle was counducted at ten locations in the Czech Republic by teflon coated pheromone traps in 2015, 2016 and 2017. The extraction of nematodes was done by macerating the captured beetles in distilled water. Determination of nematodes was done on the basic of morphological and molecular features. In total, 1704 individuals of Monochamus galloprovincialis were analyzed, 12,6 % of them carried nematodes. Following taxa of nematodes were found: Aphelenchoides sp., Aphelenchoides stammeri, Bursaphelenchus mucronatus, Contortylenchus sp., Deladenus sp., Diplogasteroides sp., Ektaphelenchoides sp., Parasitaphelenchus sp., Parasitorhabditis sp., and larvae of the order Tylenchida.
4

Phylogenetic and population genetic studies on some insect and plant associated nematodes

Saeb, Amr 22 September 2006 (has links)
No description available.
5

Étude des capacités de dispersion de Monochamus galloprovincialis vecteur du nématode du pin Bursaphelenchus xylophilus / Dispersal capacities of Monochamus galloprovincialis vector of the pinewood nematod Bursaphelenchus xylophilus

David, Guillaume 27 October 2014 (has links)
Le nématode du pin Bursaphelenchus xylophilus, originaire des Etats-Unis, est responsable de dépérissements massifs dans les forêts de pin des pays où il a été introduit. Il utilise comme vecteur un insecte du genre Monochamus, notamment M. galloprovincialis en Europe. L’objectif de cette thèse est de fournir des informations concernant les capacités de dispersion de ce coléoptère afin de mieux prédire le risque d'invasion. A l'aide d'expériences en manège de vol, nous avons montré que les adultes émergents, encore immatures, sont déjà en mesure de maintenir des vols soutenus. Ils peuvent parcourir une distance d'environ 500m par jour et les capacités de vol augmentent avec la prise de poids pendant la phase de maturation sexuelle. Il n'existe pas de compromis d'allocation de l'énergie entre fonctions de dispersion et de reproduction pendant cette période et nous proposons de qualifier ces insectes de "income breeder" et "capital disperser". A l'état mature M. galloprovincialis est capable de voler un total de 16 km, avec des vols individuels d'environ1 km; ces performances augmentent avec l'âge et le poids des insectes. Le maintien des capacités de vol tout au long de la vie adulte de M. galloprovincialis conduit à proposer que les distances potentiellement parcourues dépendent surtout de la longévité de l'insecte. Dans une expérience d'élevage en conditions contrôlées nous avons montré que la vie adulte dure au moins 4 mois, augmentant quand les fluctuations thermiques sont atténuées. Ces résultats ont des implications pour la gestion de B. xylophilus en Europe puisqu'ils démontrent que la méthode d'éradication par coupe rase sur un rayon de 500m est probablement inopérante. / The pinewood nematode (PWN) Bursaphelenchus xylophilus, native to the USA, is responsible of the pine wilt disease, causing large economic losses in the pine forests of all countries where it has been introduced. It uses as vector an insect of the genus Monochamus, e.g. M.galloprovincialis in Europe The objective of this thesis is to provide information about the dispersalabilities of, this beetle in order to better predict the spread rate of the PWN. Using flight mill experiments, we showed that immature adult beetles were able to fly since their emergence. The meanflight performance was ca. 500m per day, increasing with weight gain during the maturation period.There was no trade-offs in energy allocation between reproduction and dispersion. We therefore suggest that M. galloprovincialis is both "income breeder" and "capital disperser". Mature beetles were able to fly a total of 16km on average during their lifetime, with individual flights of ca. 1km. Flight performances increased with age and body weight, being equal for males and females. Because flight capacity remained constant across time, we suggested that the total distance potentially covered by beetles was mainly driven by their longevity. In a rearing experiment under controlled conditions we estimated the adult lifespan at 4 months. It was reduced under temperature regime with higheryearly thermal fluctuations. These results have important implications for the management of the PWN since they demonstrate that precautionary clear-cuts of 500m radius are likely to be ineffective in eradicating the disease.
6

Pušinių stiebinių nematodų (Bursaphelenchus sp.) paplitimas Lietuvoje / Distribution of pine wood nematodes Bursaphelenchus sp. in Lithuania

Kučinskas, Vaclovas 14 June 2005 (has links)
Objective – research the pine wood nematodes Bursaphelenchus sp. situation in Lithuania. Goals: 1. Research of native pine wood nematode species composition in Lithuania; 2. Research of preconditions for harmful pine wood nematode species to enter Lithuania; 3. Research of conditions for non-native pine wood nematode species to establish, breed and spread; 4. Research of consequences if harmful species becomes established in Lithuania, anticipate pest management options. Object of the study – coniferous (pine) forests in Lithuania and companies, processing imported wood. Methods. Samples were taken in coniferous clearcuts and wood processing companies from the stained wood or wood with evidence of Monochamus activities. Nematodes were extracted sing Baermann method. Preconditions for nematodes to enter Lithuania, establish and spread were analysed using statistical and literature sources. Strengths, weaknesses, opportunities, threats (SWOT) analysis was applied to the situation of Bursaphelenchus in Lithuania. Results. 27 forest enterprises and 62 wood processing companies were studied. For the first time in Lithuania non-pathogenic species Bursaphelenchus mucronatus was found. Assessement of conditions for wood nematodes in the country (import assortment and volume, countries, host plants and potential vectors), real probability for harmful species, particularly Bursaphelenchus xylophilus, to enter, establish and spread was defined. Existing quarantine system might... [to full text]

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