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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.
91

Cotton (Texas) Root Rot

Olsen, Mary 02 1900 (has links)
Revised 02/2015; Originally published: 2000. / The most important disease of woody dicotyledonous plants in Arizona is Phymatotrichopsis root rot (Cotton or Texas root rot) caused by a unique and widely distributed soil-borne fungus, Phymatotrichopsis omnivora. The fungus is indigenous to the alkaline, low-organic matter soils of the southwestern United States and central and northern Mexico.
92

Die aktive Aussen- und Sicherheitspolitik der rot-grünen Bundesregierung : 1998-2005 /

Sedlmayr, Sebastian. January 2008 (has links)
Zugl.: Berlin, Humboldt-Universiẗat, Diss.
93

Etiologia da podridão de escama da cebola no semiárido brasileiro

OLIVEIRA, Willams José de 19 February 2015 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-12-02T12:42:24Z No. of bitstreams: 1 Willams Jose de Oliveira.pdf: 1187273 bytes, checksum: 3d0f4978c0a4ad8c65c3b398bf1ec2aa (MD5) / Made available in DSpace on 2016-12-02T12:42:24Z (GMT). No. of bitstreams: 1 Willams Jose de Oliveira.pdf: 1187273 bytes, checksum: 3d0f4978c0a4ad8c65c3b398bf1ec2aa (MD5) Previous issue date: 2015-02-19 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / It was produced approximately 1,601,767 tons of onions in the 2014 harvest in Brazil, and the northeastern region with approximately 23% of this production. The culture of the onion can be affected by various diseases, among them are the bacterial rot. Between the types of decay occurring in onion bulbs stands out the scales rot because it causes significant losses in Brazil. This disease is associated with bacteria from the Burkholderia cepacea complex, Burkholderia gladioli pv. alliicola, Pseudomonas aeruginosa and Serratia marcescens. Given that for the application of efficient management measures it is necessary to understand the etiology of the disease and that it is not known for sure what the genera and species that are associated with the rot of onion scales in the semi-arid northeast, the present study have the following objectives: i) identify the bacteria involved with the disease in this region by sequencing and phylogenetic analysis of 16S rRNA region, ii) evaluate the behavior relatedness of the species identified by rep-PCR, and iii) evaluate the pathological behavior of different species identified. For this purpose, samples were taken in the main producing regions of onion in Pernambuco and Bahia semi-arid region, followed by the isolation and storage of strains in Culture Collection Rosa Mariano (CRM) of the Phytobacteriology Laboratory at the Federal Rural University of Pernambuco. We obtained 45 strains which were grouped into three clades: clade I, containing strains identified as B. cepacia complex (n = 29), clade II containing strains identified as B. gladioli (n = 10) and clade III containing strains identified as P. aeruginosa (n = 6). These strains were submitted to analysis of rep-PCR and were separated into 31 groups with level 70% of similarity. However, it was not possible to identify these three clades by this technique. When artificially inoculated in onion scales, strains of B. cepacia complex and B. gladioli were significantly more aggressive than P. aeruginosa strains. Based on phylogenetic identification performed in this study, it is concluded that the rot of onion bulb scales in the Brazilian semi-arid northeast is caused by the strains of B. cepacia complex, B. gladioli e P. aeruginosa. Moreover, more than one species of the B. cepacia complex may be associated with rot scales in this region. / O Brasil produziu aproximadamente 1.601.767 toneladas de cebola na safra de 2014, sendo a região nordeste responsável por 23% dessa produção. A cultura da cebola pode ser acometida por diversas doenças, destacando-se as podridões bacterianas. Dentre os tipos de podridões que ocorrem em bulbos de cebola destaca-se a podridão de escamas, a qual pode causar perdas de até 50% no Brasil. Essa doença está associada a bactrérias do complexo Burkholderia cepacea, Burkholderia gladioli pv. alliicola, Pseudomonas aeruginosa e Serratia marcescens. Visto que para aplicação de medidas de manejo eficientes faz-se necessário o conhecimento da etiologia da doença e que ainda não se sabe ao certo quais são os gêneros e espécies que estão associadas à podridão de escamas da cebola no semiárido nordestino, o presente estudo teve como objetivos: i) identificar as bactérias envolvidas com a doença nessa região por meio de sequenciamento e análise filogenética da região 16S rRNA, ii) avaliar o comportamento genético das espécies identificadas por meio de rep-PCR, e iii) avaliar o comportamento patológico das diferentes espécies identificadas. Para isto foram realizadas coletas nas principais regiões produtoras de cebola do semiárido Pernambucano e Baiano, seguindo-se o isolamento e depósito dos isolados na Coleção de Culturas Rosa Mariano (CRM) do Laboratório de Fitobacteriologia da Universidade Federal Rural de Pernambuco. Foram obtidos 45 isolados, os quais foram agrupados em três clados: clado I, contendo isolados identificados como sendo do complexo B. cepacia (n= 29), clado II, contendo isolados de identificados como B. gladioli (n=10) e clado III, contendo isolados identificados como P. aeruginosa (n=6). Esses isolados foram submetidos a análises de rep-PCR, sendo separados em 31 grupos ao nível de 70 % de similaridade. No entanto, não foi possível identificar esses três clados por meio desta técnica. Quando artificialmente inoculados em escamas de cebola, os isolados do complexo B. cepacia e de B. gladioli foram significativamente mais agressivos do que os isolados de P. aeruginosa. Com base na identificação filogenética realizada no presente estudo, conclui-se que a podridão de escamas de bulbos de cebola no semiárido nordestino brasileiro é causada por isolados do complexo B. cepacia, B. gladioli e P. aeruginosa. Além disso, mais de uma espécie do complexo B. cepacia pode estar associada à podridão de escamas nessa região.
94

Kalkyl mot verkligt utfall : Analys av kalkyler och kalkylverktyg med avseende på ROT-projekt / Difference between calculated and actual cost : Analysis and evaluation of calculations regarding ROT-projects

Mladenovic, Aleksandar, Sjöström, Thomas January 2014 (has links)
När det handlar om ROT-projekt (renovering, om- och tillbyggnad) är det viktigt för entreprenören att uppnå långsiktig lönsamhet. För att säkerhetsställa detta är det av stor vikt att upprätta noggranna kalkyler som håller under hela byggprojektet. I dagsläget finns små marginaler för eventuella kostnadsökningar därmed ytterst lite utrymme för misstag. Eftersom förutsättningarna vid ROT-projekt ständigt varierar beroende på typ av badrum och skadeorsak är det därför väldigt svårt att uppskatta och beräkna kostnader utifrån rådande förutsättningar.  Utifrån detta finns det ett behov hos entreprenören att förstå varför kalkylerna avviker och hur man kan undvika detta i framtida projekt. Examensarbetet innehåller både en analys av kalkylerade kostnader och dess verkliga utfall samt en analys av kalkylverktyget Meps. Då ROT-sektorn är stor och omfattande har vi valt att avgränsa oss till badrumsrenoveringar som en följd utav vattenskador. Utifrån analys av kalkyler och kalkylverktyget samt intervjuer med parter både från entreprenör och från beställarsidan har vi kommit fram till en rad slutsatser om hur företaget kan ta fram noggrannare kalkyler i framtiden. Framförallt anser vi att företaget ska föra en tätare dialog med försäkringsbolagen för att vara en del i utvecklingen av kalkylverktyget. Vi anser även att man bör avsätta resurser för att utveckla erfarenhetsåterföringen inom företaget. / It is important for the contractor to have an accurate calculation throughout the whole project, especially when it comes to ”ROT”-projects (renovation and reconstruction).There is very little room for mistakes since the budget is very tight. Since the conditions always differ from one project to another it’s very important to take this into account. Due to this there is a great need for the contractor to understand why the calculations do not add up in the end so they can avoid income losses in the future. This report contains both an analysis of the calculated costs and the outcome for five different projects and also an analysis of the program used for calculating the costs, Meps. Since the ROT-sector is big and comprehensive we have decided only to analyse bathroom renovations due to water damages. From the analysis of the calculations and Meps together with interviews with contractors and clients we have come to the following conclusions: First of all we suggest that the entrepreneur should have a closer dialogue with the insurance company to be a part of the development of Meps. We also suggest that they should devote more resources for feedback in the company.
95

Sorghum improvement as biofuel feedstock: juice yield, sugar content and lignocellulosic biomass.

Godoy, Jayfred Gaham Villegas January 1900 (has links)
Master of Science / Department of Agronomy / Tesfaye Tesso / Sorghum [Sorghum bicolor (L.) Moench] is listed as one of the potential feedstock sources for biofuel production. While sorghum grain can be fermented into ethanol in a similar way as maize, the greatest potential of the crop is based on its massive biomass and sugar rich juices. Thus development of the crop as alternative energy source requires improvement of these traits. The objectives of this study were (1) to determine the mode of inheritance of traits related to ethanol production and identify suitable genetic sources for use in breeding programs, and (2) to evaluate the potential of low lignin mutations for biomass feedstock production and assess biotic stress risks associated with deployment of the mutations. The study consisted of three related experiments: (i) estimating the combining ability of selected sweet and high biomass sorghum genotypes for biofuel traits and resistance to stalk lodging, (ii) determine the impact of brown mid-rib mutations on biofuel production and their reaction to infection by Macrophomina phaseolina and Fusarium thapsinum, and (iii) assess the reaction of low lignin mutants to green bug feeding. In the first experiment six sorghum genotypes of variable characteristics (PI193073, PI257602, PI185672, PI195754, SC382 and SC373) were crossed to three standard seed parent lines ATx3042, ATx623 and ATx399. The resulting hybrids and the parents were evaluated at four locations, three replications during 2009 and 2010 seasons. Data were collected on phenology, plant height, juice yield, °brix score and biomass production. In the second experiment, two brown mid-rib mutations (bmr6 and bmr12) and their normal versions were studied in four forage sorghum backgrounds (Atlas, Early Hegari, Kansas Collier and Rox Orange). The experiment was planted in four replications and at 14 d after flowering five plants in a plot were artificially infected with F. thapsinum and another five with M. phaseolina. The plants were harvested and rated for disease severity (lesion length and nodes crossed). Another five normal plants in each plot were harvested and used to determine biofuel traits (juice yield, ºbrix score and biomass). In the third experiment, a subset of entries evaluated in experiment II and three tolerant and susceptible checks were tested for greenbug feeding damage. Biotype K greenbug colony was inoculated to each genotype using double sticky foam cages. Feeding damage was assessed as percent chlorophyll loss using SPAD meter. There was significant general combining ability (GCA) effect among the male entries for juice yield, stem obrix and biomass production indicating that these traits are controlled by additive genes. Lines PI257602 and PI185672 in particular, had the highest GCA for all the traits and should serve as excellent breeding materials. There was no significant difference among the bmr mutants and between the bmr and normal genotypes for both stalk rot and greenbug damage. In conclusion, juice yield, °brix and biomass are largely controlled by additive genes and hence are amenable to genetic manipulation. The bmr mutations despite their impact on lignin content do not increase risk of attack by stalk rot pathogens and greenbugs and thus can be deployed for biofuel production without incurring losses to these factors.
96

Pathological and physiological studies on the brown rot fungus Monilinia fructicola (Winter) Honey

El-Zayat, Mohamed Mahmoud Sayed Ahmed. January 1965 (has links)
Call number: LD2668 .T4 1965 E52 / Master of Science
97

Phymatotrichum (Cotton or Texas) Root Rot in Arizona

Streets, R. B. 15 September 1937 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
98

Pathogenicity and Pathological Histology of Phymatotrichum Omnivorum (the fungus causing Cotton or Texas Root Rot) in a Woody Perennial - The Pecan

Brinkerhoff, Lloyd A., Streets, R. B. 06 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
99

Genome-wide SNP identification and QTL mapping for black rot resistance in cabbage

Lee, Jonghoon, Izzah, Nur K., Jayakodi, Murukarthick, Perumal, Sampath, Joh, Ho J., Lee, Hyeon J., Lee, Sang-Choon, Park, Jee Y., Yang, Ki-Woung, Nou, Il-Sup, Seo, Joodeok, Yoo, Jaeheung, Suh, Youngdeok, Ahn, Kyounggu, Lee, Ji Hyun, Choi, Gyung Ja, Yu, Yeisoo, Kim, Heebal, Yang, Tae-Jin January 2015 (has links)
BACKGROUND: Black rot is a destructive bacterial disease causing large yield and quality losses in Brassica oleracea. To detect quantitative trait loci (QTL) for black rot resistance, we performed whole-genome resequencing of two cabbage parental lines and genome-wide SNP identification using the recently published B. oleracea genome sequences as reference. RESULTS: Approximately 11.5 Gb of sequencing data was produced from each parental line. Reference genome-guided mapping and SNP calling revealed 674,521 SNPs between the two cabbage lines, with an average of one SNP per 662.5 bp. Among 167 dCAPS markers derived from candidate SNPs, 117 (70.1%) were validated as bona fide SNPs showing polymorphism between the parental lines. We then improved the resolution of a previous genetic map by adding 103 markers including 87 SNP-based dCAPS markers. The new map composed of 368 markers and covers 1467.3 cM with an average interval of 3.88 cM between adjacent markers. We evaluated black rot resistance in the mapping population in three independent inoculation tests using F₂:₃ progenies and identified one major QTL and three minor QTLs. CONCLUSION: We report successful utilization of whole-genome resequencing for large-scale SNP identification and development of molecular markers for genetic map construction. In addition, we identified novel QTLs for black rot resistance. The high-density genetic map will promote QTL analysis for other important agricultural traits and marker-assisted breeding of B. oleracea.
100

FACTORS AFFECTING VIABILITY OF STRANDS OF PHYMATOTRICHUM OMNIVORUM (SHEAR) DUGGAR.

ABDUL SATTAR, MUSTAFA HASSAN. January 1983 (has links)
Declining infestations and the cyclic appearance of Phymatotrichum root rot of cotton from season to season led to the suggestion that antagonistic microorganisms were the cause of this phenomenon. This study was concerned primarily with Actinomycetes spp., fluorescent Pseudomonads, Trichoderma spp., and other fungi. There was a continuous fluctuation in the population of Actinomycetes spp. and fluorescent Pseudomonads on the surface of strands. Populations of these antagonistic organisms dropped as the viability of strands of P. omnivorum decline. Comparison of the rhizoplane microflora from infected and healthy roots showed no relationship between the populations of Actinomycetes spp. and fluorescent Pseudomonads and the resistance of healthy roots to invasion by P. omnivorum. Similarly, soil samples collected from areas with declining infestations and assayed for populations of Actinomycetes spp. and fluorescent Pseudomonads, revealed no differences in the populations of these antagonistic organisms. This indicates that the absence of the disease in areas with declining infestations is not due to the microorganisms investigated in this study. Higher mortality rates of strands of P. omnivorum occurred when strands were exposed to Actinomycetes spp. and fluorescent Pseudomonads or to their metabolites. The hyphal deformation observed on strands from the field could not be reproduced in vitro. The same antagonistic microorganisms sprayed on cotton roots containing strands failed to reduce strand viability.

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