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Soil solarization and soil additives as alternatives to preplant fumigation in annual plasticulture strawberry productionDas, Sanghamitra 04 October 2018 (has links)
Fumigation before strawberry (<i>Fragaria×ananassa</i> Duchesne) planting was a common practice as they are susceptible to numerous pests. Methyl bromide, the colorless, odorless gas, was the chosen fumigant for growers until it was classified as an ozone-depleting substance and its use was gradually restricted and legally phased in 2015. Fumigant use has constraints and thus research on other preplant alternatives for soil sterilization of strawberry annual plasticulture production is necessary. This research focused on soil solarization, products including paper pellets, mustard seed meal, and corn gluten meal. Two studies were conducted at the Virginia Tech Hampton Road AREC (Agricultural Research and Extension Center), and follow-up studies at the Flanagan Farm in Virginia Beach. The first study at the AREC evaluated three-week soil solarization with and without pelleted products. The second study evaluated different rates of paper pellets, paper pellets plus mustard seed meal, mustard seed meal alone and fumigated plots. The purpose of each study was to evaluate the sterilization-mulching effects on weeds, plant health and stand count, yield and fruit parameters (as size and sweetness). A container-grown plant study determined if there was any phytotoxic effect of paper pellets and mustard seed meal on pansies (Viola tricolor). Another study evaluated the effect of paper pellets and mustard seed meal on germination of different weed species. The paper pellet and soil solarization treatments showed decreased early season weeds but season-long weed control was not provided by the same treatment. In the study one, paper pellet improved yield in the first season but not the second season. Paper pellet and mustard seed meal increased yield compared to the black plastic control in the second study. No phytotoxicity was observed on pansies in response to paper pellet and mustard seed meal rates. In the grower farm study, weed biomass was higher under the clear tarp than the black tarp perhaps due to more light transmission under the clear tarp. A new locally available paper pellet product was used at the grower farm and the plants in plots treated with this product, had lower health rating and yield compared to other treatments. / PHD / The strawberry fruit is not a typical fruit but develops from the receptacle and is well known for the bright red color, fleshy fruit and characteristic aroma. Growing strawberries is challenging as they are susceptible to soil-borne pests. Preplant fumigation was commonly accomplished by the use of methyl bromide (MB) to ensure the soil-borne pests are adequately controlled; until MB use as a fumigant was phased out by the Montreal Protocol Act. Use of fumigants require maintaining a fumigant management plan, a buffer zone between the treatment area and high population zone areas, and worker safety practices. There is a need to evaluate alternative preplant pest control strategies as soil solarization and mulching treatments that would not compromise on berry yield and quality. Two experiments were conducted at the Virginia Tech Hampton Roads Agricultural Research and Extension Center, Virginia Beach.
One experiment conducted in 2014-15 and 2015-16 evaluated soil solarization (a method where moistened soil is covered with a clear tarp, traps solar radiation, and thereby heats up the soil), and mulching treatments (paper pellet mulch, mustard seed meal, and corn gluten meal) used alone or in combination with soil solarization and their effect on weed control, crop growth, crop yield, and fruit quality. In the second study rates of paper pellets, mustard seed meal (alone or in combination of these), and fumigated plots were evaluated to study the effect on strawberry plants. The most effective treatments from the two studies were used in an experiment at a grower’s farm. A shorter duration of soil solarization (three week) with paper pellet showed lower early weed density than black plastic control, but overall solarization did not have consistent beneficial effect on yield. Paper pellets disintegrate over time and the pellets being porous to water; they were not an effective tool for weed control. However, combination of paper pellets and mustard seed meal showed a beneficial effect on yield compared to the black plastic control treatments. The plots covered with black tarp had less weed biomass than those covered with clear tarp in the grower farm study
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Fusarium wilt of watermelons in CyprusPoullis, Constantinos Andreas January 2000 (has links)
No description available.
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ECOLOGICAL WEED MANAGEMENT FOR ORGANIC FARMING SYSTEMSLaw, Derek M. 01 January 2006 (has links)
Two field studies examining direct ecological weed control practices were conducted in Lexington, Kentucky. The first evaluated weed control efficacy and influence on yields of several mulches in two organically-managed bell pepper (Capsicum annum) production systems for two years. Peppers were planted in double rows in flat, bare ground or on black polyethylene-covered raised beds with drip irrigation, and four mulches (straw, compost, wood chips, and undersown white dutch clover (Trifolium repens L.) living mulch) were applied to the two production systems. In both years, polyethylene-covered raised beds produced higher yields than the flat, bare ground system. In the second year, the polyethylene-covered bed system coupled with mulching in-between beds with compost or wood chips after cultivation provided excellent weed control and yields. The second field study evaluated the efficacy of soil solarization and shallow cultivation on the invasive and noxious weed johnsongrass over two years (Sorghum halapense). A soil solarization treatment, using clear plastic stretched over soil for eight weeks, and a cultivated bare fallow treatment, utilizing a tractor pulled cultivator implement equipped with sweep blades, were randomly applied during the summers of 2003 and 2004 to a field infested with johnsongrass. Solarized and cultivated plots in both years were lightly tilled 8 months after completion of the initial treatment period. At the conclusion of the experiment the johnsongrass population was significantly reduced in all treatments and in the control plots compared to the original infestation. These two experiments testing direct weed control practices (mulching, cultivation, solarization) were undertaken in the context of an ecological weed management plan that includes long term strategies to reduce weed infestations such as crop rotation, cover cropping, and fertility management that are essential for organic farmers.
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Ciklas „Apsilankymas sename dvare“ / Cycle "A visit in old manor "Masiliūnaitė, Birutė 15 January 2007 (has links)
Everybody of us forming our life by minds and words. If your view to some possibility is limited, so this bound becoming reality for you.
L. Hay
By the cycle of pictures „A visit in old manor“, with surrealism and minimalism stylistics, photography, solarization effect and serigraphy. I tried to convey my view to human‘s communication problem, in which final a person is stuffing to the frame of loneliness. The rhythm of our life everyday becoming more crazy, more fast, sometimes you can‘t to catch then you are comming alone and not necessary to anybody. I tried to see difference between loneliness and wish to be alone.
The problem, which i analyse, put to the cycle of eleven works „A visit in old manor“. With the my view to surrealism, i putted a human inside to an old, deserted manor, locked him in a walls of building. Minimalism helped with minimal implements: upstarting and disappearing text, fragments of map, birds, colors – to give a chanse for loner to communicate. All works have his name - numeration ASD1, ASD2, ...ASD10, ASD11, letters reflect a cycle‘s name, the number – the succession of works and my view to starting and progressing problem and the way to solve it.
In the description i have acquainted reader with techniques, which i used in this work, their performance ways, authors, who had influenc to my indidual artistical touch and style. I am acquainting not only with verbal form, but also with visual. With this work you will know a part of me. That i... [to full text]
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Biodiversidade funcional da microbiota e promoção de crescimento de plantas de alface por Pseudomonas spp. fluorescentes em substrato solarizado / Microbial functional biodiversity and lettuce growth promotion by rhizobacteria in solarized substrateDonzeli, Vanessa Polon 26 January 2006 (has links)
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Previous issue date: 2006 / Resumo: A solarização do solo vem se destacando como um método promissor para o controle de fitopatógenos; no entanto, as mudanças nas populações e atividades microbianas após o processo de solarização são ainda pouco estudadas. O presente trabalho teve como objetivos: estudar parte da comunidade e atividades microbianas em solo solarizado em comparação a solo não solarizado; selecionar isolados de rizobactérias promotoras de crescimento em alface em substrato comercial, visando à produção de mudas, e verificar os possíveis benefícios da solarização do solo à promoção de crescimento de plantas de alface por esses isolados microbianos. Para a avaliação do efeito da solarização sobre a microbiota do solo, os tratamentos foram: solarização em coletor solar (substrato solarizado e não solarizado) e amostragens no tempo (0, 30, 60, 90 e 120 dias após a solarização). As parcelas foram vasos com 2L de substrato (mistura de solo e substrato orgânico cama-de-frango), mantidos com plantas da variedade de alface crespa Verônica. Os parâmetros avaliados foram: carbono, nitrogênio e relação entre C e N da biomassa microbiana; liberação de CO2; quociente metabólico; microrganismos amonificadores, nitrificadores, celulolíticos, amilolíticos e proteolíticos; Pseudomonas spp. fluorescentes e bactérias não fluorescentes no substrato e na rizosfera de plantas de alface; número de folhas, matéria seca da parte aérea e raízes de alface e emergência de plantas invasoras. Para avaliar a promoção de crescimento de mudas de alface utilizaram-se um substrato comercial para hortaliças, com metade da adubação recomendada, solarizado e não solarizado e 50 isolados de Pseudomonas spp. da coleção do IAC. Os isolados foram escolhidos de acordo com um pré-teste e resultados de Freitas et al.(2003) e Sotero (2003) . O delineamento experimental foi o inteiramente casualizado, com 10 repetições, totalizando 1000 vasos. Vinte e cinco dias após a semeadura, as mudas de alface foram coletadas e realizou-se a contagem do número de folhas e avaliação da massa de matéria seca da parte aérea.
A solarização do substrato causou uma redução da microbiota logo após ser realizada, refletida pela diminuição do carbono e nitrogênio da biomassa microbiana, microrganismos amonificadores, nitrificadores, celulolíticos, amilolíticos e bactérias não fluorescentes. O aumento da relação C/N da biomassa microbiana na primeira amostragem e a redução da liberação de CO2 pela respiração de microrganismos do solo e aumento do quociente metabólico aos 30 dias após a solarização também foram indicativos da alteração na microbiota. No entanto, com o tempo, a microbiota do substrato solarizado se restabeleceu, sendo que aos 30 dias após a solarização alguns grupos de microrganismos, como os amonificadores e amilolíticos, já haviam tido seu número igualado aos do substrato não solarizado e outros grupos como os nitrificadores e celulolíticos apresentaram-se em maior número no substrato solarizado nessa amostragem. Nem todos os grupos de microrganismos foram imediatamente afetados pela solarização, como os microrganismos proteolíticos, que tiveram o seu número diminuído apenas na amostragem feita aos 60 dias, as também se restabeleceram nas amostragens seguintes. As Pseudomonas spp. do grupo fluorescente foram positivamente influenciadas pela solarização, tendo seu número aumentado aos 60 dias no substrato e 120 dias na rizosfera. Assim, aos 90 dias, a maioria dos grupos microbianos funcionais já havia voltado ao equilíbrio, com exceção apenas dos nitrificadores e Pseudomonas spp. fluorescentes que se apresentaram em número maior no substrato solarizado na amostragem seguinte. As plantas de alface cultivadas em substrato solarizado tiveram maior crescimento na primeira amostragem após a solarização e nesse tratamento houve uma redução média de 92,3% na emergência de plantas invasoras. A solarização do substrato favoreceu o efeito benéfico de 17 isolados de Pseudomonas spp. fluorescentes na promoção de crescimento de mudas de alface e favoreceu também o efeito deletério de dois isolados. Dezoito isolados foram capazes de promover o crescimento de mudas de alface, independente da solarização, e a solarização também foi responsável pelo maior crescimento das plantas, independente da inoculação de rizobactérias / Abstract: Soil solarization has been reported as an efficient soil disinfestations method for controlling soil borne pathogens; however few studies about changes in microbial activity and populations after soil polarization have been published. The present work was carried out to study the microbial activity and part of the microbial community in solarized soil; selected plant growth promoting rhizobacteria strains in commercial substrate to seedling yield and verify the possible contribution of soil solarization to promotion of lettuce seedling growth by these microbial strains. To evaluate the effect of solarization on the soil microorganisms, the treatments were: solarization in solar collector (solarized and non solarized substrate) and time sampling (0, 30, 60, 90 and 120 days after solarization). The plots bowls (2L) were maintained with lettuce plants of cultivar Verônica. The following parameters were evaluated: carbon, nitrogen and C/N in the microbial biomass; basal respiration; metabolic quotient; number of ammonifying, nitrifying, cellulolytic, amylolytic, proteolytic microorganisms and fluorescent and non fluorescent bacteria grown in B King media, in bulk substrate and lettuce rhizosphere; number of leafs, shoot and root dry matter and weed emergence. To evaluate promotion of seedling lettuce growth a substrate for production of vegetable seedlings was used, with half-full fertilizer, solarized and non solarized, and fifty pseudomonads strains of the IAC collection. The experiment had a completely randomized design in 1000 plots. Twenty five days after sowing the number of leafs and the shoot dry matter lettuce were evaluated. The substrate solarization immediately reduced the microbial groups as showed by carbon and nitrogen in microbial biomass, ammonifying, nitrifying, cellulolytic, amylolytic microorganisms and fluorescent bacteria decrease. The increase of the C/N in microbial biomass ratio in the first sampling and decrease of the CO2 evolved rate and higher metabolic quotient rate at 30 days after substratesolarization indicated changes in microbial community. However, after some time, the functional microbial groups were reestablished. Thirty days after solarization the number of some groups of microorganisms ¿ as ammonifying and amylolytic microorganisms ¿ were similar in solarized and non solarized substrate, and others ¿ as nitrifying and cellulolytic microorganisms ¿ ad higher numbers in solarized substrate in this sampling. Proteolytic microorganisms were not affected immediately by solarization and decreased only in the samplings 60 days after solarization. In the samplings 90 and 120 days after solarization the number of proteolytic were similar in the treatments. Fluorescent pseudomonads were positively affected by solarization: the number of these bacteria was higher in the bulk solarized substrate in third sampling and in the rhizosphere in fifth sampling. Thus, at 90 days, most of functional microbial groups were reestablished, except nitrifying and fluorescent pseudomonads, that were in higher number in solarized substrate. The solarization contributed to increase the growth of lettuce plants in first sampling and provided effective weed control that were reduced 92,3% over the untreated control. Solarization propitiated the beneficial effect of 17 fluorescent Pseudomonas spp. strains, that promoted seedling lettuce growth, and deleterious effect of 2 strains on lettuce seedlings. Eighteen Pseudomonas spp. Strains promoted plant growth, independent of solarization, and solarization promoted plant growth, independent of bacteria inoculation / Doutorado / Microbiologia / Doutor em Genetica e Biologia Molecular
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Managing Slash to Minimize Colonization of Residual Leave Trees by Ips and Other Bark Beetle Species Following Thinning in Southwestern Ponderosa PineDeGomez, Tom, Fettig, Christopher J., McMillin, Joel D., Anhold, John A., Hayes, Christopher 05 1900 (has links)
12 pp. / Pine Bark Beetles, THE PIÑON IPS BARK BEETLE, FIREWOOD AND BARK BEETLES IN THE SOUTHWEST, USING INSECTICIDES TO PREVENT BARK BEETLE ATTACKS ON CONIFERS, GUIDELINES FOR THINNING PONDEROSA PINE FOR IMPROVED FOREST HEALTH AND FIRE PREVENTION / Various techniques to reduce brood production of Ips and Dendroctonus spp. in ponderosa pine slash are discussed.
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Sobrevivência em microcosmo e em campo solarizado de fitopatógenos submetidos à fermentação acelerada de diferentes matériais orgânicosAmbrósio, Márcia Michelle de Queiroz [UNESP] 21 February 2006 (has links) (PDF)
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ambrosio_mmq_dr_botfca.pdf: 919131 bytes, checksum: 0f21215000fd16709fe15c433c0e4d28 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A solarização é uma das alternativas de controle físico para vários fitopatógenos que podem sobreviver por vários anos no solo por meio de estruturas de resistência, causando danos em muitas culturas, e muitas vezes inviabilizando vastas áreas agrícolas. No entanto, existem algumas espécies que possuem temperatura letal acima daquela atingida pela solarização do solo. Vem sendo estudado a incorporação de material orgânico previamente a colocação do plástico, situação esta que promove o aprisionamento dos gases oriundos da decomposição, conferindo um efeito aditivo à solarização. O objetivo do presente trabalho consistiu na prospecção de materiais orgânicos promissores para produzir voláteis fungitóxicos capazes de controlar fitopatógenos de solo. Foram realizados dois ensaios em condições de microcosmo (câmara de vidro) para simular a solarização do solo, onde incorporou-se 1kg/m2 de material orgânico fresco e posteriormente, dois experimentos de campo, em épocas diferentes e em áreas contíguas com os mesmos materiais orgânicos. No primeiro experimento foi incorporado 1kg/m2 de material orgânico e no segundo 3Kg/m2. Estudou-se quatro fitopatógenos (Fusarium oxysporum f. sp. lycopersici Raça 2; Macrophomina phaseolina; Rhizoctonia solani AG-4 HGI e Sclerotium rolfsii) frente a quatro 2 materiais orgânicos frescos e triturados incorporados ao solo (folhas e ramos de brócolos, eucalipto, mamona e mandioca brava). O controle dos fungos foi avaliado por meio da análise da sobrevivência das estruturas em meio semi-seletivo específicos, durante quatro períodos (7, 14, 21 e 28 dias do início do experimento). Nos experimentos de campo, foram monitoradas a temperatura por um coletor de dados Tipo CR23X (Campbell Scientific) e a porcentagem de CO2 e de O2 pelo equipamento analisador de gases (Texto 325-1)... . / Solarization is one of the physical control alternatives available against a number of plant pathogens capable of surviving for several years in the soil by means of resistance structures, causing damage to many crops, and often rendering vast agricultural areas unviable. However, there are a few species whose lethal temperature is above the temperature reached during soil solarization. The incorporation of organic material prior to mulching with plastic is currently being studied. This condition promotes the trapping of gases from decomposition, imparting an additive effect to solarization. The objective of the present work consisted in the investigation of organic materials which are promising to produce fungitoxic volatiles that can control soil plant pathogens. Two assays were carried out under microcosmic conditions (glass chamber) to simulate soil solarization, in which 1kg/m2 of fresh organic material were incorporated. Later, two field experiments were carried out during different seasons and at contiguous areas, using the same organic materials. In the first experiment, 1kg/m2 of organic material was incorporated, while 3Kg/m2 were incorporated in the second. Four plant pathogens (Fusarium oxysporum f. sp. lycopersici Strain 2; Macrophomina phaseolina; Rhizoctonia solani AG-4 HGI, and Sclerotium rolfsii) were studied under four types of fresh, ground organic materials incorporated into the soil (leaves and branches of broccoli, eucalyptus, castor bean, and wild cassava). Fungus control was evaluated through the analysis of the survival of structures in a specific semi-selective medium, during four periods (7, 14, 21, and 28 days from the beginning of the experiment). In 4 the field experiments, temperature was monitored with a Type CR23X (Campbell Scientific) data collector, and CO2 and O2 percentages were monitored with a Testo 325-1 gas analyzer equipment. In both field experiments...(Complete abstract, click electronic address below)
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Solarization as a means to eliminate invasive plant species and target the seedbankReed, Garret W. 01 January 2009 (has links)
The Calaveras River is a unique riparian habitat in San Joaquin County, influenced by both tidal water from the San Francisco Bay and impounded rainwater from the New Hogan Dam. The Calaveras River is one of the few river systems in California that does not benefit from snowpack melt. This dynamic system has changed dramatically in both its species composition and hydrodynamic regime due to years of human influences. What was once a thriving population of native plant species has become an environment dominated almost completely by aggressive exotic invasive species. The goal of this project was to remove the nonnative plant habitat by the most cost effective and least labor intensive means. The study area was along a section of river that bisects the University of Pacific campus in Stockton, California. From years of invasive species presence a deep seedbank has developed within the soil which acts to reduce the effectiveness of native plant reintroductions. A technique known as "solarization" was used to eliminate the seedbank and to facilitate the survival of native plants. Tarps were used to eradicate existing plants followed by disturbance of the soil and watering to induce germination of subsoil weed seeds. As the new plant seedlings emerge, tarps are reapplied to eliminate that generation of seedbank plants. After four time series of tarping and watering, a significant difference was found between control plots and treatments utilizing the solarization technique. Treatment 2, which consisted of tarping without weight, was determined to best target the seedbank after four repetitions and resulted in reducing invasive species in the seed bank.
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Controle biológico, físico e químico de Phytophthora palmivora em plântulas de mamoeiro cv. sunrise solo. / Biological, physical and chemical control of Phytophthora palmivora on papaya seedlings cv sunrise soloCarnaúba, Juliana Paiva 22 February 2006 (has links)
The papaya culture is extensively cultivated in the world, where Brazil meets as
worldwide the producing greater. Amongst the problems main inherent to the culture, the
root and fruit rots are distinguished, caused by Phytophthora palmivora. The present work
had for objective to control P. palmivora in seedling of papaya cv. Sunrise solo, through
methods of biological, physical and chemical control. They had been tested four
Trichoderma isolated (T. koningii - T3; T. harzianum - T13; Trichoderma sp. - T152D and
T. polysporum - TP) and five fungicides "in vitro" (copper oxychloride - 2; 3 e 4g/L;
mancozeb - 2; 3 e 4g/L; metalaxyl + mancozeb - 2,5; 3,5 e 4g/L; thiophanate-methyl - 6; 7
e 8g/L and carbendazim - 0,5; 1,0 e 1,5mL/L) and "in vivo", as well as the solarization of
the substratum in solar collectors. They had been made still, test of volatile, not volatile
metabolites and hyperparasitism for the Trichoderma isolated. In the biological control "in
vitro", used the plate technique, while in the in vivo control, the substratum was dealt
with Trichoderma of isolated and integrated form, before the infestation of the ground. In
the chemical control, the fungicides had been tested "in vitro" adding them in BDA
medium, while "in vivo" the seedlings roots had been immersed during 10 minutes in the
fungicides solution. The solarization of the substratum was carried during 24, 48 and 72
hours, in solar collectors of 10 and 15 cm of diameter, becoming infested itself, previously
the substratum with the pathogen (40 mL of inocule with approximately 20 sporangia for
mL/ vase). The Trichoderma isolated T3, T13 and TP had been most efficient in the
inhibition of the growth of P. palmivora "in vitro", however, only the isolated TP produced
volatile and not volatile metabolites. On the other hand, all the isolated ones had
presented capacity to hyperparasite the pathogen. In the biological control "in vivo" no
isolated one was capable to reduce the severity of the disease. The solarization of the
substratum increased significantly the seedlings survival, when compared to the witness.
It didn t have significant differences between the periods of solar exposition, however, the
diameter of 15 cm presented one better efficiency, with 87% of seedlings survival. The
products most efficient in the pathogen inhibition "in vitro" had been oxicloreto de cobre,
mancozeb and metalaxyl + mancozeb, while "in vivo" the five fungicides had presented
similar efficiency, not having significant difference between the dosages tested. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A cultura do mamoeiro é extensamente cultivada no mundo tendo o Brasil como o maior
produtor. Dentre os principais problemas inerentes à cultura, destacam-se as podridões
do pé e do fruto, causadas por Phytophthora palmivora. O presente trabalho teve por
objetivo avaliar o controle de P. palmivora em plântulas de mamoeiro cv. Sunrise solo,
utilizando métodos de controle biológico, físico e químico. Foram testados quatro
isolados de Trichoderma (T. koningii - T3; T. harzianum - T13; Trichoderma sp. - T152D e
T. polysporum - TP) e cinco fungicidas in vitro (oxicloreto de cobre - 2; 3 e 4g/L;
mancozeb 2; 3 e 4g/L; metalaxyl + mancozeb 2,5; 3,5 e 4g/L; tiofanato metílico 6; 7
e 8g/L; e carbendazim 0,5; 1,0 e 1,5mL/L) e in vivo na dosagem recomendada pelo
fabricante, bem como a solarização do substrato em coletores solares. Foram feitos
ainda, testes de metabólitos voláteis, não voláteis e hiperparasitismo para os isolados de
Trichoderma. No controle biológico in vitro , utilizou-se a técnica de confrontamento em
cultivo pareado, enquanto no controle in vivo , o substrato foi tratado com os isolados de
Trichoderma de forma isolada e integrada, antes da infestação do solo com o patógeno.
No controle químico, os fungicidas foram testados in vitro adicionando-os ao meio BDA,
enquanto in vivo as raízes das plântulas foram imersas durante 10 minutos na solução
dos fungicidas. A solarização do substrato foi realizada durante 24, 48 e 72 horas, em
coletores solares de 10 e 15 cm de diâmetro, infestando-se, previamente o substrato
com o patógeno (40 mL do inoculo com aproximadamente 20 esporângios por mL /
vaso). Os isolados de Trichoderma T3, T13 e TP foram os mais eficientes na inibição do
crescimento de P. palmivora in vitro , no entanto, apenas o isolado TP produziu
metabólitos voláteis e não voláteis. Por outro lado, todos os isolados apresentaram
capacidade de hiperparasitar o patógeno. Já no controle biológico in vivo nenhum
isolado foi capaz de reduzir a severidade da doença. A solarização do substrato
aumentou significativamente a sobrevivência das plântulas quando comparada à
testemunha. Não houve diferenças significativas entre os períodos de exposição solar,
entretanto, o diâmetro de 15 cm apresentou uma melhor eficiência, com 87% de
sobrevivência das plântulas. Os produtos mais eficientes na inibição do patógeno in
vitro foram oxicloreto de cobre, mancozeb e metalaxyl + mancozeb, enquanto in vivo
os cinco fungicidas apresentaram eficiência semelhante, não havendo diferença
significativa entre as dosagens testadas.
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Sobrevivência em microcosmo e em campo solarizado de fitopatógenos submetidos à fermentação acelerada de diferentes matériais orgânicos /Ambrósio, Márcia Michelle de Queiroz, 1976- January 2006 (has links)
Orientador: Nilton Luiz de Souza / Banca: Edson Luiz Furtado / Banca: Roberto Lyra Villas Bôas / Banca: Alfredo Seiti Urashima / Banca: Flávia Rodrigues A. Patricio / Resumo: A solarização é uma das alternativas de controle físico para vários fitopatógenos que podem sobreviver por vários anos no solo por meio de estruturas de resistência, causando danos em muitas culturas, e muitas vezes inviabilizando vastas áreas agrícolas. No entanto, existem algumas espécies que possuem temperatura letal acima daquela atingida pela solarização do solo. Vem sendo estudado a incorporação de material orgânico previamente a colocação do plástico, situação esta que promove o aprisionamento dos gases oriundos da decomposição, conferindo um efeito aditivo à solarização. O objetivo do presente trabalho consistiu na prospecção de materiais orgânicos promissores para produzir voláteis fungitóxicos capazes de controlar fitopatógenos de solo. Foram realizados dois ensaios em condições de microcosmo (câmara de vidro) para simular a solarização do solo, onde incorporou-se 1kg/m2 de material orgânico fresco e posteriormente, dois experimentos de campo, em épocas diferentes e em áreas contíguas com os mesmos materiais orgânicos. No primeiro experimento foi incorporado 1kg/m2 de material orgânico e no segundo 3Kg/m2. Estudou-se quatro fitopatógenos (Fusarium oxysporum f. sp. lycopersici Raça 2; Macrophomina phaseolina; Rhizoctonia solani AG-4 HGI e Sclerotium rolfsii) frente a quatro 2 materiais orgânicos frescos e triturados incorporados ao solo (folhas e ramos de brócolos, eucalipto, mamona e mandioca brava). O controle dos fungos foi avaliado por meio da análise da sobrevivência das estruturas em meio semi-seletivo específicos, durante quatro períodos (7, 14, 21 e 28 dias do início do experimento). Nos experimentos de campo, foram monitoradas a temperatura por um coletor de dados Tipo CR23X (Campbell Scientific) e a porcentagem de CO2 e de O2 pelo equipamento analisador de gases (Texto 325-1)... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: Solarization is one of the physical control alternatives available against a number of plant pathogens capable of surviving for several years in the soil by means of resistance structures, causing damage to many crops, and often rendering vast agricultural areas unviable. However, there are a few species whose lethal temperature is above the temperature reached during soil solarization. The incorporation of organic material prior to mulching with plastic is currently being studied. This condition promotes the trapping of gases from decomposition, imparting an additive effect to solarization. The objective of the present work consisted in the investigation of organic materials which are promising to produce fungitoxic volatiles that can control soil plant pathogens. Two assays were carried out under microcosmic conditions (glass chamber) to simulate soil solarization, in which 1kg/m2 of fresh organic material were incorporated. Later, two field experiments were carried out during different seasons and at contiguous areas, using the same organic materials. In the first experiment, 1kg/m2 of organic material was incorporated, while 3Kg/m2 were incorporated in the second. Four plant pathogens (Fusarium oxysporum f. sp. lycopersici Strain 2; Macrophomina phaseolina; Rhizoctonia solani AG-4 HGI, and Sclerotium rolfsii) were studied under four types of fresh, ground organic materials incorporated into the soil (leaves and branches of broccoli, eucalyptus, castor bean, and wild cassava). Fungus control was evaluated through the analysis of the survival of structures in a specific semi-selective medium, during four periods (7, 14, 21, and 28 days from the beginning of the experiment). In 4 the field experiments, temperature was monitored with a Type CR23X (Campbell Scientific) data collector, and CO2 and O2 percentages were monitored with a Testo 325-1 gas analyzer equipment. In both field experiments...(Complete abstract, click electronic address below) / Doutor
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