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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.
111

Analyzing Tuberculosis Vulnerability and Variables in Tarrant County

McGlone, John Francis 12 1900 (has links)
Over 9 million new cases of tuberculosis (TB) were reported worldwide in 2013. While the TB rate is much lower in the US, its uneven distribution and associated explanatory variables require interrogation in order to determine effective strategies for intervention and control. However, paucity of case data at fine geographic scales precludes such research. This research, using zip code level data from 837 confirmed TB cases in Tarrant County obtained from Texas Department of State Health Services, explores and attempts to explain the spatial patterns of TB and related risk markers within a framework of place vulnerability. Readily available census data is then used to characterize the spatial variations in TB risk. The resulting model will enable estimations of the geographic differences in TB case variables using this readily available census data instead of time-consuming and expensive individual data collection.
112

Chemical control of soybean rust (Phakopsora pachyrhizi) on soybeans.

Du Preez, Eve Diane. January 2005 (has links)
Soybean rust (SBR) caused by Phakopsora pachyrhizi Syd. is an aggressive wind dispersed fungal disease which has spread around the world at an alarming rate in the last decade. The disease was first reported in South Africa (SA) in 2001. It has become well established in the province of KwaZulu-Natal. Reports are occasionally made from eastern Mpumalanga, late in the growing season, in years with good rainfall. Yield losses of 10 - 80% have been reported due to SBR infection. Literature was reviewed to better understand the pathogen in an attempt to find suitable disease management strategies. Many strategies involve delaying, rather than preventing, SBR infection. Of the two strategies to prevent infection, the use of fungicides was the only option for disease control in SA, as no resistant cultivars are available. Field trials were conducted to determine which fungicides are effective in controlling SBR. Further research was conducted to determine the timing, frequency and rate of fungicide applications for optimal control of SBR. Trials were evaluated for disease severity, seed yield and the effect of fungicides on seed quality. Fungicides from the triazole class of the sterol biosynthesis inhibiting group of fungicides were found to be the most effective in controlling SBR. A fungicide from the strobilurin group was found to be less effective than the triazoles at the suggested rate, but was found to be as effective when evaluated at higher dosage rates. Triazoles premixed with fungicides from the benzimidazole and strobilurin groups were also effective in controlling SBR. Timing of application was found to be critical for strobilurin fungicides, but not for triazole fungicides, which have a curative ability, unlike strobilurins. Strobilurin fungicides applied preventatively, before the appearance of disease symptoms were as effective as triazole fungicides applied after disease symptoms, but before infection levels had reached 10%. Across both wet and dry seasons two fungicide applications applied at 21d intervals at the R2 growth stage resulted in effective disease control. In wet seasons, a third fungicide application resulted in yields that were higher, albeit not statistically significant, than two fungicide applications. Assessments of individual fungicides for optimal dosage rate found that registered rates were already optimal for some fungicides, but for others it appeared as if alterations were necessary to the rate suggested for registration. This study was one of the first to extensively evaluate the efficacy of the new triazole and strobilurin fungicides on SBR control. The results have been shared globally, but particularly with newly affected countries in South and North America. Although this research has been groundbreaking, there are still many aspects of fungicide control which need to be studied in order to further optimise chemical control of SBR. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005
113

Studies on Phakopsora pachyrhizi, the causal organism of soybean rust.

Nunkumar, Archana. January 2006 (has links)
Phakopsora pachyrhizi H. Syd and P. Syd, the causal organism of soybean rust (SBR) was first reported in Japan in 1902. In 1934 the pathogen was found in several other Asian countries and as far south as Australia. In India, SBR was first reported on soybeans in 1951. There have been several early reports of SBR in equatorial Africa but the first confirmed report of P. pachyrhizi on the African continent was in 1996 from Kenya, Rwanda and Uganda. Since then, the pathogen has spread south with reports from Zambia and Zimbabwe in 1998 and in Mozambique in 2000. In February 2001, P. pachyrhizi was first detected on soybeans near Vryheid, in Northern KwaZulu-Natal, South Africa (SA). As the season progressed, the disease was observed in other parts of the province, and epidemic levels were found in the Cedara, Greytown, Howick and Karkloof production regions. Soybean rust subsequently spread to Amsterdam and Ermelo in the Highveld region of SA. The disease reappeared in SA in March 2002. It is now established that the pathogen is a threat to soybean production in the country with yield losses in the region of 10-80%. A literature review on SBR investigating the taxonomy of the pathogen, its morphology, symptoms, host range, infection process, epidemiology, control options and the economic importance of P. pachyrhizi was complied to provide the necessary background information to conduct research under local conditions and to assist in interpretation of results of experiments. Epidemiological trials were conducted at the University of KwaZulu-Natal under controlled environmental conditions in a dew chamber and conviron. Development of P. pachyrhizi on the susceptible cultivar (LS5995) was quantified in combinations of seven temperatures (15,19,21,24,26,28 and 30°C) and five leaf wetness durations (LWD) (6,9,12,14 and 16hrs) at three relative humidities (RH) (75%, 85% and 95%). Studies indicate that optimum temperature for uredospore infection is 21-24°C with a LWD greater than 12hrs and RH 85-95%. The number of pustules as well as lesion size on the abaxial and adaxial leaf surface increased with increasing LWD at all the RH values tested. Infection did not occur on plants incubated at 15°C and 30°C at 85% or 95%RH whereas at 75%RH infection did not occur on plants incubated at 15°C, 19°C and 30°C regardless of LWD. Number of pustules per lesion produced at 75%, 85% and 95%RH was highest at 24°C and showed a gradual increase with increasing LWD. Lesion size on both leaf surfaces increased after 12hrs LWD at 24°C at 75% and 85%RH whereas at 95%RH lesion size increased after 14hrs LWD at 24°C. Exposure of uredospores to ultraviolet light which is equivalent to ultraviolet C (sunlight) which is < 280nm, shows a decrease in germination (7%). Under continuous darkness, the germination percentage was found to range from 58% after 48 hrs. Germination was found to peak at 16hrs in darkness with a gradual decrease as time increased whereas germination under ultraviolet light was highest after 6hrs with a gradual decrease with increased exposure to light. Germ tube lengths were found to be shorter when exposed to ultraviolet light (107µm) compared to controls kept in the dark (181µm). Results obtained clearly show a negative effect of ultraviolet light on the germination and germ tube length of uredospores. A 0.1 ml suspension of uredospores on 1.25% water agar Petri dishes was exposed to cycles of 14h ultraviolet light and 10h darkness for 48h. Results indicate an increase in germination percentage of uredospores when exposed to 10h of darkness following a 14h period under ultraviolet light. Controlled environmental studies were conducted to determine alternative hosts of P. pachyrhizi in SA. The control used in this experiment was Prima 2000, a susceptible cultivar to soybean rust. Seven legume plants [Cajanus cajan (L.) Huth, Glycine max (L.) Merr, Lablab purpureus (L.) Sweet, Lupinus angustifolius (L.) Finnish, Phaseolus vulgaris (L.), Pueraria lobata (M&S) Wild and Vigna unguiculata (L.) Walp] and three dry bean lines (Bonus; OPS-RS2 and PAN 159) showed typical SBR symptoms when rated after 21 days post inoculation with uredospores for percentage disease severity. Disease severity was significantly different within the alternative hosts, but G. max, P. vulgaris and P. lobata were not significantly different from Prima 2000 (control). A uredospore suspension of 2.5 x 10(5) uredospores ml(-1) from plants that showed typical SBR symptoms was made and inoculated on to Prima 2000, a susceptible soybean cultivar. Uredospores from pustules on G. max, L. purpureus, L. angustifolius, P. vulgaris, P. lobata, V. unguiculata, Bonus and PAN 159 produced viable uredospores on PRIMA 2000. These plants are considered alternative hosts of P. pachyrhizi. Effect of leaf age on susceptibility of soybean to SBR was tested under controlled environmental conditions. Mean number of lesions as well as lesion size were greater on younger leaves than on older leaves of plants at the same physiological age. Plants at the early vegetative and reproductive stages had a significantly lower number of lesions as well as a smaller lesion size. Plants at the V6 and R1 growth stages were significantly more susceptible to P. pachyrhizi than plants at other developmental stages. Trichoderma harzianum Rifai, Eco-77® a commercial biological control product, was evaluated for its efficacy as a biological control agent of P. pachyrhizi. Trichoderma harzianum sprayed at the standard concentration on infected soybean plants was significantly more effective in controlling P. pachyrhizi than plants sprayed at 1/2X and 2x the standard concentration. This was noted in both Trial 1 and 2. Data indicate that spraying the filtrate two days after inoculation produces less disease. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
114

Modelling avian influenza in bird-human systems : this thesis is presented in the partial fulfillment of the requirement for the degree of Masters of Information Science in Mathematics at Massey University, Albany, New Zealand

Zhao, Yue January 2009 (has links)
In 1997, the first human case of avian influenza infection was reported in Hong Kong. Since then, avian influenza has become more and more hazardous for both animal and human health. Scientists believed that it would not take long until the virus mutates to become contagious from human to human. In this thesis, we construct avian influenza with possible mutation situations in bird-human systems. Also, possible control measures for humans are introduced in the systems. We compare the analytical and numerical results and try to find the most efficient control measures to prevent the disease.
115

Management of reproductive tract infections among health providers and in the community in Lao People's Democratic Republic /

Sihavong, Amphoy, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
116

Epidemiology and eradication of bovine viral diarrhoea virus infections : studies on transmission and prenatal diagnosis of persistent infection /

Lindberg, Ann, January 2002 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2002. / Härtill 6 uppsatser.
117

Hormetic UV treatments for control of plant diseases on protected edible crops

Scott, George January 2017 (has links)
Hormesis is a dose response phenomenon where low doses of a stress bring about a positive response in the organism undergoing treatment. UV-C hormesis has been known for over three decades and has a broad range of benefits on postharvest produce. Benefits include increased nutritional content, delayed chlorophyll degradation and disease resistance. The beneficial effects have been observed on many varieties of fresh produce including climacteric and non-climacteric fruit, tubers, salads and brassicas. The majority of previous studies have used low-intensity (LIUV) UV-C sources. LIUV sources require lengthy treatment times, which are in the region of 6 minutes for tomato fruit. This has, in part, prevented the commercial application of this technique. High-intensity, pulsed polychromatic light (HIPPL) sources, however, have recently been developed. HIPPL sources may have the potential to drastically reduce treatment times and increase their commercial viability. It was shown, here, that the use of HIPPL can control disease (reduce disease progression) caused by Botrytis cinerea and Penicillium expansum and also delay ripening on tomato fruit. Both disease control and delayed ripening were at similar levels for LIUV and HIPPL treatments on mature green fruit. The HIPPL treatments used in these studies can reduce treatment times for tomato fruit by 97.3%. Both HIPPL and LIUV treatments elicit local responses irrespective of the treatment orientation and tomato fruit, therefore, require full surface irradiation. Furthermore, UV-C in the HIPPL source is not required for disease control or delayed ripening. It does, however, contribute approximately 50% towards the total observed effects. Investigations into the mechanisms underpinning postharvest HIPPL and LIUV hormesis, on tomato fruit, identified that the expression of genes involved in plant hormone biosynthesis, defence, secondary metabolism and ripening were affected. This indicates that disease control is achieved through induced resistance. Changes to expression, following treatment, were highly similar for both HIPPL and LIUV treatments and were mediated by salicylic acid, jasmonic acid and ethylene. This may lead to broad range resistance against necrotrophic and biotrophic pathogens as well as abiotic stresses and herbivorous pests. Recently, the exposure of foliage to UV-C has been shown to induce resistance against B. cinerea on Arabidopsis thaliana. The horticultural applications of such treatments, however, have not been explored. Pre-harvest treatments of lettuce in the glasshouse showed variation in damage threshold and optimal treatment to control disease following LIUV and HIPPL treatment. Further sources of variation included the cultivar, pathogen of interest and the point that treatment was applied during the year. Using a controlled environment allowed seasonal variation to be mitigated and both HIPPL and LIUV treatments controlled disease against B. cinerea. For pre-harvest treatments to be a success in the glasshouse, further studies into how both biotic and abiotic factors influence treatment is required. To circumvent the problems associated with pre-harvest treatments and environmental variation in the glasshouse, LIUV seed treatments were performed on tomato. Control of B. cinerea was established with an approximately 10% reduction in incidence and disease progression with a 4 kJ/m2 treatment. When monitoring the effect of treatment on germination and early seedling development it was also identified that an 8 kJ/m2 treatment led to biostimulation of germination and root and shoot growth.
118

Agente de controle de endemia (ACE): trajetória de uma ocupação profissional - Estudo de caso do município de Niterói/RJ.

Almeida, Claudia Márcia Osório Xavier de January 2012 (has links)
Submitted by Mario Mesquita (mbarroso@fiocruz.br) on 2014-11-10T15:54:17Z No. of bitstreams: 1 Claudia_Almeida_EPSJV_Mestrado_2012.pdf: 4597494 bytes, checksum: b79ca3aac48688166ae47f21eba2468d (MD5) / Approved for entry into archive by Mario Mesquita (mbarroso@fiocruz.br) on 2014-11-10T18:48:43Z (GMT) No. of bitstreams: 1 Claudia_Almeida_EPSJV_Mestrado_2012.pdf: 4597494 bytes, checksum: b79ca3aac48688166ae47f21eba2468d (MD5) / Made available in DSpace on 2014-11-10T18:48:43Z (GMT). No. of bitstreams: 1 Claudia_Almeida_EPSJV_Mestrado_2012.pdf: 4597494 bytes, checksum: b79ca3aac48688166ae47f21eba2468d (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Escola Politécnica de Saúde Joaquim Venâncio. Programa de Pós-Graduação em Educação Profissional em Saúde. / Nesta dissertação, discute-se a Educação Profissional do trabalhador de nível médio sem formação específica em saúde - o Agente de Controle de Endemias (ACE). Além disso, numa perspectiva de complementaridade, são abordados os conceitos de qualificação e de competência profissional. A formação foi tratada do ponto de vista histórico, sendo necessária a discussão de alguns aspectos das políticas sociais, além dos modelos de gestão em saúde que embasaram a política de Educação Permanente em Saúde no Sistema Único de Saúde (SUS). Verifica-se na metodologia desta política a identificação e validação de um conjunto de competências profissionais num sistema complexo de trabalho. O estudo incidiu sobre os ACE no município de Niterói/RJ e permitiu concluir pela existência de uma dimensão bastante complexa entre a formação e a exigência prática do trabalho, enquanto elementos políticos estruturantes da Vigilância em Saúde. Apontamos que, na década de 2000, foi executada uma política de formação num padrão de excelência pelo PROFORMAR/EPSJV/FIOCRUZ. / This dissertation discusses the Professional Education of the average worker without specific training in health – Agent of Endemic Disease Control (ACE). In addition, a complementary perspective, discusses the concepts of qualification and professional competence. The training was handled in the historical point of view, it was necessary to discuss some aspects of social policies, and management models that support the health policy of Permanent Education in Health System Health Checks on the methodology of this policy identification and validation of a set of professional skills in a complex system of work. The study focused on the agents of ACE in country city Niterói/RJ, and concluded that there is a very complex dimension between training and work practice requirements, whil e structuring the political elements of Surveillance in Health points out that in 2000s, ran a training policy in a standard of excellence by PROFORMAR EPSJV/FIOCRUZ.
119

Saúde escolar no ensino fundamental: subsídios para a prevenção e controle da infecção / School health in primary education: subsidies for the prevention and control of infections

Débora Fernanda Amaral Pedrosa 10 July 2015 (has links)
Introdução. Afastamentos associados com as doenças infecciosas estão entre as principais causas de absenteísmo de escolares. A legislação atual não dispõe sobre os conteúdos ou as disciplinas que deveriam abordar a importância da higiene das mãos para se evitar a transmissão de doenças infecciosas, tornando necessário investigar como as escolas lidam com o assunto. Objetivo. Expor algumas reflexões sobre os Parâmetros Normativos e Matrizes Curriculares, especificamente o tema transversal relacionado à saúde e contextualizar as condições de infraestrutura para higiene nas escolas do ensino fundamental do Município de Uberaba, MG. Material e métodos. Primeiramente, realizou-se uma análise documental seguida de uma revisão integrativa da literatura. Posteriormente, conduziu-se um estudo observacional-seccional (diagnóstico situacional). Para a busca foram utilizadas as bases de dados periódicos CAPES, SciELO, LILACS, MEDLINE, PubMed, CINAHL e Ministério da Educação. A observação estruturada ocorreu em visitas agendadas nas escolas, e foi utilizado um instrumento de observação validado. Os dados foram submetidos à análise descritiva. Resultados. A educação é garantida pela Constituição de 1.988 a todos os brasileiros, demonstrando uma preocupação do Estado em manter as crianças nas escolas. Entretanto, a legislação relacionada com o ensino dos temas transversais e questões de saúde surgiu somente dezenove anos mais tarde. Atualmente, as matrizes escolares tratam do tema higiene nos conteúdos de Ciências e Educação Física, porém esse assunto também foi encontrado em Geografia e História. Pesquisas internacionais mostram que as crianças têm baixa adesão na higienização das mãos, o que pode favorecer o surgimento de doenças infecciosas e parasitárias. As escolas do município de Uberaba que foram visitadas possuíam infraestrutura adequada, porém os insumos para a higiene das mãos não eram, em sua maioria, disponibilizados nos banheiros. Conclusão. A legislação mostra a preocupação do Estado com a Educação e a Saúde dos escolares, entretanto, parece haver um hiato na aplicabilidade entre essas leis e a prática. A revisão da literatura internacional revela que as intervenções educativas no ensino fundamental acarretam redução do absenteísmo por infecções. Todavia, as publicações nacionais não permitiram estabelecer tal associação. As escolas estudadas oferecem a infraestrutura física para a higiene dos escolares, entretanto, serão necessários esforços adicionais para conscientizar profissionais e escolares para a disponibilização e uso adequado dos insumos requeridos para a higiene das mãos / Introduction. Clearances associated with infectious diseases are among the leading causes of school absenteeism. The current legislation does not dispose of the contents and subjects that should address the importance of hand hygiene to prevent the transmission of infectious diseases, making it necessary to investigate how schools deal with this issue. Objective. Expose some reflections on the Regulatory Parameters and Course curricula, specifically health related cross-cutting themes, and contextualize the infrastructure conditions for hygiene in primary schools of the city of Uberaba, Minas Gerais, Brazil. Methodology. First, we carried out a document analysis followed by an integrative literature review. Subsequently it was conducted an observational-sectional study (situation analysis). For the search we used the CAPES databases (journals and theses and dissertations), SciELO, LILACS, MEDLINE, PubMed, CINAHL, Ministry of Education and the Brazilian Digital Library of Theses and Dissertations (BDTD). The structured observation occurred in scheduled visits in schools, and we used a validated instrument of observation. Data were submitted to descriptive analysis. Results. Education is guaranteed by the Constitution of 1988 to all Brazilians, demonstrating a concern of the state to keep children in schools. However, the legislation related to the teaching of cross-cutting issues and health issues emerged only nineteen years later. Currently, the school headquarters deal with the subject hygiene in content Sciences and Physical Education, but this subject has also been found in Geography and History. International research shows that children have lower compliance in hand hygiene, which can encourage the emergence of infectious and parasitic diseases. Schools in the city of Uberaba that were visited had adequate infrastructure, but the inputs for hand hygiene were not mostly available in the bathrooms. Conclusion. The Brazilian law shows the state\'s concern for the Education and the Health of school, however, there seems to be a gap in the applicability of these laws and practice. The international literature review reveals that educational interventions in primary education entails reducing absenteeism infections. However, national publications have failed to establish such an association. The studied schools provide the physical infrastructure for the hygiene of the students, however, additional efforts are needed to educate professionals and school for the appropriate provision and use of items necessary for hand hygiene
120

Efeito de extratos de albedo de laranja (Citrus sinensis) e dos indutores de resistência ácido salicílico, acilbenzolar-s-metil e Saccharomyces cerevisiae no controle de Phyllosticta citricarpa (Teleomorfo: Guignardia citricarpa). / The effect of orange (citrus sinensis) albedo extracts the resistance inducers with salicylic acid, acilbenzolar-s-methyl and saccharomyces cerevisiae on the control of phyllosticta citricarpa (teleomorph: guignardia citricarpa).

Julio Alves Cardoso Filho 25 April 2003 (has links)
A mancha preta dos citros (MPC) é uma doença que limita a exportação de laranja brasileira para o Japão e países da Europa. Exceto para Citrus aurantium e seus híbridos, todas as outras variedades são susceptíveis ao patógeno. O fungo Guignardia citricarpa, descoberto por Kiely em 1948 em New South Wales na Austrália, é o estádio sexual do agente causal da MPC e a sua fase imperfeita é Phyllosticta citricarpa. Uma importante característica da MPC é seu longo período de latência. A infecção pode ser efetuada por ascósporos e picnidiósporos. A lesão nos frutos fica restrita ao flavedo (epicarpo), sendo que o fungo não infecta o albedo (mesocarpo). O albedo é rico em celulose, carboidratos solúveis, pectinas, compostos fenólicos (flavonóides), aminoácidos e vitaminas. Os compostos fenólicos presentes nas plantas são produtos do metabolismo secundário, e podem ser resultantes da interação planta-ambiente e podem sintetizados como resposta ao ataque de fitopatógenos. Os fenólicos presentes nos citros incluem flavonóides, antocianinas, coumarinas e psorolenos entre outros. Estes compostos podem exibir ação antimicrobiana e antiviral e podem contribuir controle da MPC. A aplicação de fungicidas é o método de controle da MPC. Uma outra possibilidade de controle seria a ativação de fatores de resistência através do uso de indutores bióticos (Saccharomyces cerevisiae) e abióticos (Bion e ácido salicílico). Deste modo, este trabalho teve como objetivos estudar os efeitos do uso de extratos aquosos, metanólicos e etanólicos de albedo de laranja na germinação formação de apressório e crescimento micelial de P. citricarpa in vitro, bem como avaliar o uso da indução de resistência para o controle da MPC através dos indutores S. cerevisiae, Bion e ácido salicílico em pós e pré-colheita em frutos de laranja ‘Pêra-Rio’ e folhas de limão ‘Siciliano’. Os resultados experimentais mostraram que os extratos de albedo, nas concentrações de 10 e 100 mg / mL de água, foram capazes de inibir em 100% a germinação, formação de apressório e o crescimento micelial de P. citricarpa. Foi observado que os extratos, dependendo da concentração, podem ter ação fungicida ou fungistática. No tocante a utilização de S. cerevisiae, Bion e ácido salicílico, aplicados em pós-colheita, foi observado que estes agentes não foram capazes de impedir o desenvolvimento de novas lesões em frutos de laranja ‘Pêra-Rio’. Também foi constatado que S. cerevisiae e Bion, aplicados em pré-colheita, não foram capazes de induzir resistência contra P. citricarpa em folhas de limão ‘Siciliano’ inoculadas previamente a campo com G. citricarpa. Nesse sentido, sugere-se que outros estudos sejam conduzidos, principalmente no que se refere ao uso potencial de extratos do albedo de laranja como medida alternativa de controle da MPC. / Black spot of citrus (CBS) has been a limiting factor in the export of brazilian oranges to Japan and European countries and Japan. Except for Citrus aurantium and its hybrids, all commercially growing Citrus spp. are susceptible to the pathogen. The fungus Guignardia citricarpa, discovered by Kiely in 1948 in New South Wales, is the sexual stage of the causal agent of CBS and Phyllosticta citricarpa is the imperfect stage. An important characteristic of CBS is the long latent period after infection. The infection is carried out by ascospores and pycnidiospores. The fungicidal application is the most important method of control of CBS. The CBS lesion in citrus fruits is limited to the flavedo, since P. citricarpa does not infect the albedo. The albedo is rich in cellulose, soluble carbohydrates, pectin, phenolic compounds, amino acids and vitamins. The phenolics present in the plants are secondary metabolic products and are believed to be produced as a result of the plant interaction with the enviromment and synthesized as a response to attempted phytopathogen attacks. The phenolics that occur in Citrus include flavonoids, anthocyanins, coumarins and psorolens. These compounds may exhibit antiviral and antimicrobial activities, and may contribute to the control of CBS disease. An another possibility to the CBS control is the activation of factors resistance by the use of abiotics (Bion and salicylic acid) and biotics (Saccharomyces cerevisiae) “plant defence activator” (inducers). Therefore, the objectives of this paper were to study the in vitro effects of aqueous, ethanolic and methanolic albedo orange extracts on the germination, appressorium formation and mycelial growth of P. citricarpa as well as to evaluate the use of the S. cerevisiae, Bion and salicylic acid as “plant defence activator” at post and preharvest conditions in fruit of “Pêra-Rio” and leaves of ’Siciliano’ lemon. The results showed that the use of albedo extracts, 10 and 100 mg per mL of water, inhibited 100 % the germination, appressorium formation and mycelial growth of P. citricarpa. It was also observed that the extracts of albedo, depending upon the concentration, exhibited fungicidal or fungistatic activity. The use of S. cerevisiae, Bion and salicylic acid at postharvest conditions did not affect the development of new lesions of CBS in ‘Pêra-Rio’ orange fruit. It was also observed that the use of S. cerevisiae and Bion at preharvest conditions, did not induce resistance against P. citricarpa in leaves of ‘Siciliano’ lemon naturally infected with G. citricarpa under field conditions. Thus, it is suggested that other studies be carried out, mainly regarding the potential of orange albedo’s extracts as a alternative method for CBS control.

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