EA - Escola de Agronomia
URI Permanente desta comunidade
Navegar
Navegando EA - Escola de Agronomia por Por Orientador "Araújo, Leila Garcês de"
Agora exibindo 1 - 8 de 8
Resultados por página
Opções de Ordenação
Item Antagonismo entre Magnaporthe oryzae e o fungo micorrízico Rhizoctonia sp.(Universidade Federal de Goiás, 2013-03-25) Carvalho, Jacqueline Campos Borba de; Kato, Lucília; Araújo, Leila Garcês de; http://lattes.cnpq.br/3488880262260757; Araújo, Leila Garcês de; Kato, Lucília; Lobo, Valácia Lemes da Silva; Filippi, Marta Cristina da Corsi diRice blast caused by the fungus Magnaporthe oryzae B. Couch [anamorfo - Pyricularia oryzae Cav.] occurs in all rice growing regions of the world. The sustainable agriculture requires the introduction of biological control as one of the components in the integrated disease management. The microorganisms associated to plants are capable of producing secondary metabolites such as alkaloids which may have a role in biological control. The objective of the present study consists, isolation and identification of secondary metabolites of the micorrhizal fungus Rhizoctonia sp. obtained from Epidendrum nocturnum and evaluate in vitro and in vivo antagonism to M. oryzae. Ten fungal isolates were used to test the antibiosis against M. oryzae. The isolate En07 of Rhizoctonia sp. exhibited a greater halo of inhibition and consequently was considered the best in vitro antagonist to M. oryzae. Crude, mycelial and lyophilized extracts of micorrhizal isolate were obtained. The analysis by CCD of these three extracts showed positive results in relation to Dragendorff, indicating the presence of phenolics. The analysis of RMN 1H and masses showed the presence of aromatic hydrogens and phenolics. Five concentrations of each extract were prepared and utilized in the studies on in vitro mycelial inhibition of M. oryzae and observed 77.86% of pathogen reduction by crude extract (700 μg/mL). Two crude extract treatments (520 μg/ml and 120 μg/ml) significantly reduced the radial growth of the pathogen compared to control. The crude extract showed best results for mycelia inhibition of the pathogen, followed by lyophilized and mycelial extracts. In two trials, the crude extract at 0.52 μg.μL-1 also reduced the formation of appressoria of M. oryzae by 100%. Two greenhouse experiments were conducted on leaf blast suppression with the cultivar Primavera, using completely randomized design with three replications. In both these trials, the mycelial extract (1860 μg/ml and M.o 3x105) showed marked reduction of leaf blast severity in relation to control by 59.27% and 77.58% respectively. In the second trial, the second treatment (1040 μg/mL and M.o3x105) of crude extract reduced AUDPC by 64.63% compared to control. The results showed that the metabolites of Rhizoctonia sp. posses great potential for biological control of rice blast.Item Bioprospecção de moléculas bioativas e antagonismo entre waitea circinata warcup & talbot e patógenos do arroz(Universidade Federal de Goiás, 2016-07-08) Carvalho, Jacqueline Campos Borba de; Filippi, Marta Cristina Corsi de; http://lattes.cnpq.br/0029536556461484; Araújo, Leila Garcês de; http://lattes.cnpq.br/3488880262260757; Araújo, Leila Garcês de; Silva, Gisele Barata da; Pasqualatto, Vanessa Gisele; Martins, Samuel Julio; Gonçalves, Fábio JoséRice is one of the most important cereal in the world, but its productivity is affected by fungal diseases such as blast, brown spot, scald, sheath rot, sheath blight and stain of the sheath. Mycorrhizal fungi are capable of producing secondary metabolites that can be used to control pathogens. This study aimed to evaluate the potential of isolated mycorrhizal and their secondary metabolites in antagonism to the rice pathogens. The isolate mycorrhizal was characterized biochemically (cell wall and co - cultivation). We evaluated the mycorrhizal mycelia efficiency as well as their extracts and compounds in the inhibition of the mycelial growth, spore germination and formation of appressorium Magnaporthe oryzae. The efficiency of the pairing of volatile and non - volatile metabolites, and the efficiency of mycelium of Waitea circinata to other rice pathogens it was conducted in two trials. Four extracts of W. circinata (crude, mycelial, lyophilized and mycelial mass) were obtained and used in in vitro assays with pathogens. The tests for the suppression of leaf blast were also conducted in the greenhouse with the mycelium, extracts and mycorrhiza compounds. The completely randomized design was used for all tests. W. circinata produces Indolacetic Acid in vitro and showed enzymatic activity of glucanase, chitinase and protease when in cultivation with wall of the pathogens and co -cultivation. The mycorrhizal mycelia inhibited the mycelial growth of all rice pathogens in vitro. The isolated mycorrhizal was efficient in vitro production of volatile and non- volatile metabolites reducing mycelial growth of Sarocladium oryzae 94.41% and 53%, respectively. The mycelium of mycorrhiza to the concentration 10 g / L reduced the growth of M. oryzae by 97.92 % and has been effective and active even after autoclaving reducing the area of the colony by 93.53%, 77.30%, 31.07% and 4.42 % of Cochliobolus miyabeanus , Monographella albescens and Rhizoctonia oryzae - Ro93 and Ro88, respectively. In greenhouse the mycelium of mycorrhiza (10g/L En07 + M.o.) suppressed leaf blast at 83.89 %. Non- volatile metabolites of W. circinata inhibited in 48.95 % growth of M. oryzae. The analysis of spectrometric high resolution mass (HRMS) showed that the extract from the mycelial mass (MME), crude extract (CE) and lyophilized extract (LE) had the same chemical profile that can be attributed to sphinganine. The MME ( 700 / mL ) at 24 hours after installation of the test reduced the formation of appressorium of M. oryzae in 75.71 %, respectively. In the greenhouse, MME + M.o. suppressed the severity of leaf blast in 77.01 % and reduced AUDPC by 92.38 %. The results of this study indicate that the MME W. circinata is promising in biocontrol of the rice diseases.Item Supressão de brusone nas folhas de arroz com Cladosporium cladosporioides.(Universidade Federal de Goiás, 2014-02-21) Chaibub, Amanda Abdallah; Filippi, Marta Cristina Corsi de; http://lattes.cnpq.br/0029536556461484; Araújo, Leila Garcês de; http://lattes.cnpq.br/3488880262260757; Araújo, Leila Garcês de; Filippi, Marta Cristina Corsi de; Faria, Fabrícia Paula de; Vieira, Bernardo de Almeida HalfeldRice blast (Magnaporthe oryzae Couch, anamorph-Pyricularia oryzae Cav.) is the major disease of rice causing yield losses up to 100%, in the world. Its control, currently held by integrating genetic resistance, cultural practices and chemical control, requires the inclusion of biological agents. The objectives of this study were to evaluate the in vitro antagonism between C. cladosporioides and four different rice pathogens; to verify the ability of C. cladosporioides in suppressing leaf blast and to study the mechanisms involved during disease suppression. The bioassays were conducted in a completely randomized design with three replications. The antagonism in vitro was evaluated by pairing-up, in Petri dishes containing PDA medium, nine different isolates of C. cladosporioides with the rice pathogens Sarocladium oryzae (sheath rot), Monographella albescens (scald), Cochliobolus miyabeanus (brown stain) and M. oryzae. All C. cladosporioides isolates reduced colonies mycelia growth up to 53.84% in addition to hallo formation. Among the nine tested isolates, four were selected for in vivo studies. Under controlled greenhouse conditions, three different concentrations were tested, in two different applications way; 1) 48 hours before challenger inoculation with M. oryzae; 2) mixture of M. oryzae and C. cladosporioides conidia suspensions. The isolated C24 C. cladosporioides (5x105) sprayed 48 hours, before challenger inoculation reduced 97.1% of leaf blast severity, and the spray mixture of conidial suspensions of C24 C. cladosporioides (5x101) and M. oryzae 3x105 spray of decreased leaf blast severity by 88.6%. Subsequently, the mechanisms involved in leaf blast suppression were investigated by using the same isolate, both applications methods and by collecting rice plants leaves sprayed with C. cladosporioides and M. oryzae. The application of C. cladosporioides 48 hours before challenger inoculation with M. oryzae and the conidial suspensions of mixture of M. oryzae and C. cladosporioides reduced to 83.9% and 78.6% of leaf blast severity, respectively. It was detected that, in the presence of C. cladosporioides and absence of the pathogen activity of enzymes GLU, LIPOX, PAL and POX increased significantly. In the presence of, C. cladosporioides and M. oryzae, POX and PAL activity and AS content also significantly increased, in both application forms. Scanning electron microscopy confirmed the physical interaction between plant/biological agent/pathogen during the penetration phase. It was proved that C. cladosporioides is a biological agent efficient in activating biochemical defense mechanisms of the rice plant during leaf blast suppression.Item Associação genômica ampla para conteúdo de proteína, óleo e ácidos graxos em soja(Universidade Federal de Goiás, 2019-12-18) Gonçalves, Bianca Muriel; Vidotti, Miriam Suzane; http://lattes.cnpq.br/0285845278783380; Araújo, Leila Garcês de; http://lattes.cnpq.br/3488880262260757; Araújo, Leila Garcês de; Coelho, Alexandre Siqueira Guedes; Martins, Saulo Muniz; Vidotti, Miriam SuzaneThere has been growing interest in breeding programs with the aim of the development of superior soybean genotypes for specific purposes, such as human feed. Therefore, traits such as protein, oil, and fatty acids content are important to achieve these purposes. The aim of this research was to identify genomic regions associated with the protein, oil, and fatty acids contents (palmitic, stearic, oleic, linoleic, and linolenic acids) in seed, in 416 soybean accessions through genome-wide association studies. The phenotypic data were obtained through a field trial carried out in augmented blocks of Federer at the experimental unit of Seagro-GO, in Senador Canedo-GO, in 2007/2008 growing season. The contents of protein, oil, and fatty acids was quantified by specific methods from the seeds. The accessions were genotyped with the Illumina Infinium SoySNP50K Bead Chip with 52.041 single nucleotide polymorphisms (SNPs) markers. It was found that there are no genetic structure patterns or kinship in the panel, an ideal condition for the analysis. Following broad genomic association analysis, twelve significant SNPs located on seven chromosomes were identified: three significant SNPs for oil and protein content in seed, two SNPs for stearic acid content in seed and one SNP for each of the remaining traits. Candidate genes included transcription factors and enzymes related directly or indirectly to the characters analyzed. Detected markers can support identify genotypes with traits of interest.Item Caracterização da variabilidade patogênica e interação diferencial de isolados de Curtobacterium flaccumfaciens pv. flaccumfaciens em feijoeiro-comum(Universidade Federal de Goiás, 2013-03-27) Lima, Stella Cristina Dias Valdo; Wendland, Adriane; Melo, Patrícia Guimarães Santos; Araújo, Leila Garcês de; http://lattes.cnpq.br/3488880262260757; Araújo, Leila Garcês de; Lourenço Júnior, Valdir; Melo, Leonardo Cunha; Wendland, AdrianeThe common bean (Phaseolus vulgaris L.) is cultivated throughout the year in many regions of Brazil, in three different growing seasons, resulting in a estimated harvest (2012/2013) of 3,4 million tons. As a consequence of being cultivated in many ecosystems, this crop is exposed to many abiotic factors, accentuating losses and making it more susceptible to pathogens. Among the economically relevant diseases, the bacterial wilt, caused by Curtobacterium flaccumfaciens pv. flaccumfaciens can cause production losses of up to 90%. The Curtobacterium flaccumfaciens pv. flaccumfaciens colonizes the xylematic vessels, blocking the transport of water and nutrients to the upper part of the plant and causing mosaic, flaccidity, wizen leaf board, wizen leaf burn, wilt and death. In Brazil, C. flaccumfaciens pv. flaccumfaciens was found for the first time in 1995, during the “rainy season” in the State of São Paulo. Currently, it is found in many other States, Parana, Santa Catarina, Goiás, Distrito Federal and Mato Grosso do Sul. For identifying C. flaccumfaciens pv. flaccumfaciens, morphological and biochemical methods were efficient, as well as the iniciators CffFOR2-CffREV4 were specific in PCR reaction for the 24 isolates. The preservation methods Castellani, filter paper and phosphate-glycerol buffer were efficient to maintain the viability of Cff isolates (Multifunctional Microorganisms Collection, Embrapa Arroz e Feijao) innoculated in Ouro Branco, BRS Esplendor and CNFP10132. According to the Scott & Knott test (1974), four groups of different aggressiveness were formed. Among these, eight isolates were chosen, two from each aggressivity group, for “race” identification, diferential interaction studies and identification of resistant genotypes. The innoculation of 30 genotypes of common bean enabled the identification of a differential interaction between the C. flaccumfaciens pv. flaccumfaciens isolates and the genotypes of the common bean. The genotypes IPA 9, Ouro Branco and Michelite were the most resistant ones, and the genotypes CNFRS 11997 and Frijólica 0-3-1 were the most susceptible ones. The isolates CNPAFCff25 and CNPAFCff 04 were the most aggressive ones, and the isolates CNPAFCff33 and CNPAFCff11 were the least aggressive ones. The methodology of partial diallel Melo & Santos (1999) allowed the classification of eight races and fifteen differential cultivars. After innoculation with the most aggressive isolate CNPAFCff 25 and the least aggressive isolate aggressive CNPAFCff 31, the analysis of scanning electron microscopy images revealed the formation of tangled structures resistance structures in genotypes Ouro Branco and IPA 9, whereas no such structures were observed in the moderately resistant genotype Diacol Calima and the susceptible genotypes CNFRS 11997 and CNFC 10429. Employing the methodology of stability Wricke was possible to identify genotypes which contributed most to the interaction effects, so the genotypes indicated to compose the differential series. The methodology of Lin and Binns possible to analyze the behavior of genotypes demonstrating that they have followed the principles of gene-gene theory.Item Relações filogenéticas entre isolados fúngicos de Cyrtopodium saintlegerianum Rchb. f., de Epidendrum nocturnum Jacq. (Orchidaceae) e de Rhizoctonia spp. Fitopatogênicas ao arroz e ao feijão(Universidade Federal de Goiás, 2013-03-21) Luzini, Aline Pereira; Araújo, Leila Garcês de; http://lattes.cnpq.br/3488880262260757; Collevatti, Rosane Garcia; https://orcid.org/ 0000-0002-3733-7059; Araújo, Leila Garcês de; Collevatti, Rosane Garcia; Pereira, Marlon Corrêa; Coelho, Alexandre Siqueira GuedesThe orchids Cyrtopodium saintlegerianum (epiphyte) and Epidendrum nocturnum (rupicola) occur in areas anthropized of cerrado and cerrado rupestre, respectively. Even though, Rhizoctonia sp. is pathogenic to various crops, it is one of the more frequent genera among the microrrhizal fungi. Studies on fungal phylogenetics utilizing the ITS (Internal Transcribed Spacer) region of rDNA are important for evaluating specificity between plant and fungus, the evolutionary history of species and host - pathogen interactions. The objective of the present study include molecular characterization and establishment of phylogenetic relationships among endophytic/micorrhizal fungi isolates of C. saintlegerianum and of E. nocturnum pertaining to genera Rhizoctonia sp., Xylaria sp. and isolates of Rhizoctonia spp. pathogenic to rice and common beans and of isolates obtained from Genbank. The genomic DNA of one micorrhizal isolate, two of Xylaria sp. (endophytic), and four of rice and bean pathogens were extracted, and soon after sequencing of ITS 1 and ITS2 of nrDNA was done. The phylogenetic relations, inferred by Bayesian analysis among the rhizoctonia-like isolates of the present study and found in GenBank showed three clusters, and Xylarioides showed one cluster. The molecular results of micorrhizal Rhizoctonia sp. and Xylariodes are in close agreement with the results on morphology. The micorrhizal isolates formed one poliphyletic clad with the isolates of the GenBank. The micorrhizal isolate of Rhizoctonia sp. obtained from E. nocturnum formed one lineage different from Rhizoctonia spp. originating from other orchid species of GenBank. The Xylarioides isolates obtained in the present study showed lineage different of the found in GenBank.Item Caracterização fenotípica e molecular de Xanthomonas axonopodis pv. phaseoli e Xanthomonas fuscans subsp. fuscans procedentes de regiões produtoras de feijoeiro-comum no Brasil(Universidade Federal de Goiás, 2014-02-25) Paiva, Bruna Alicia Rafael de; Wendland, Adriane; http://lattes.cnpq.br/7196405181790361; Araújo, Leila Garcês de; http://lattes.cnpq.br/3488880262260757; Araújo, Leila Garcês de; Borba, Tereza Cristina de Oliveira; Coelho, Gesimária Ribeiro Costa; Wendland, AdrianeThe Common bacterial blight caused by Xanthomonas axonopodis pv. phaseoli (Xap) and Xanthomonas fuscans subsp. fuscans (Xff), is one of most important bacterial etiology diseases from the common bean plant. This pathogen causes a great loss in the production, mainly in the “water” harvest, when the environmental conditions are helpful to the development of this disease and to its dissemination. Among the strategies about integrated handling of diseases, the genetic resistance is the main measure of control and, for obtaining some cultivate with lasting resistance and of notorious specter, it is important to the know the genetic pathogen diversity. The present work has the goal of studying the diversity and the genetic structure around and inside the population of Xap and Xff using the markers rep-PCR; to connect the genetic pathogen diversity with its geographical distribution inside Brazilian producing common bean plant regions. There were obtained 42 Xap and Xff isolated and four Xanthomonas isolated not pathogens of to the bean plant, originated in the States of São Paulo, Goiás, Paraná and Rio Grande do Sul. The genetic profiles obtained by primers BOX, ERIC and REP produced 12 haplotipes matched (HC), where the HC 3, specific xff, was more frequent in PR and GO, and was not found in RS. The dendrogram produced through the analysis showed that Xap, Xff and isolated not pathogens are genetically different. In the analysis of genetic structure, the total genetic diversity (Ht), among three populations was 0,2385 revealing that there was variability from a population to the other one. Higher values of the Shannon rate (0,3648) show that Xap population is more different genetically. From a total of 51 locos, 94,12 % are polymorphic, inside Xap population they are all polymorphicand inside Xff, only 18,18 % are polymorphic. The genetic differentiation coefficient (Gst = 0,5194) revealed diversity inside and among the patogenic populations, confirming AMOVA’s result, where 51,98 % of the diversity was among the populations and 48,06 % inside them. Then, the technique helped how to find differences between Xap and Xff and measure the values of genetic diversity among and inside populations. The results of this study give us much information about the pathogens diversity, which is considered useful to identify and to characterize the resistant germoplasm in a more efficient way.Item Estudo de resistência à murcha-de-fusarium e identificação de QTLs em feijeiro-comum(Universidade Federal de Goiás, 2017-04-27) Valdo, Stella Cristina Dias; Wendland, Adriane; http://lattes.cnpq.br/7196405181790361; Araújo, Leila Garcês de; http://lattes.cnpq.br/3488880262260757; Wendland, Adriane; Gonçalves, Fábio José; Coelho, Alexandre Siqueira Guedes; Filippi, Marta Cristina Corsi; Araújo, Leila Garcês deThe common bean (Phaseolus vulgaris) crop plays an important role in the culture and economy of Brazil. It is cultivated in all Brazilian regions and is affected by several diseases like fusarium wilt which is caused by Fusarium oxysporum f. sp. phaseoli (soil-born fungus). This disease brings significant losses in common bean culture and genetic resistance is the primary form of control. One of the core goals of breeding programs is the development of resistant cultivars, therefore the objectives of this work are: i) To select F. oxysporum f. sp. phaseoli resistant F5:7 lines resulted from the crossing between Ouro Branco X CNFP10132, under controlled field and environment conditions ii) To identify SSR markers and QTL-linked SNPs associated with the resistance of common bean to fusarium wilt using 92 recombinat inbred lines(RILs) resulted from the crossing between Ouro Branco x CNFP10132. In the first study, 140 lines, the breeders Ouro Branco and CNFP10132, BRS Esplendor (resistant) and BRS Supremo (susceptible) as controls were evaluated. Field trials were conducted in a center pivot area where natural infestation of the pathogen occurs. The treatments were evaluated in summer and winter crop and the experimental design used was 12x12 triple lattice. The two controlled environment trials were conducted in a completely randomized design. The treatments were inoculated by cutting and immersing the roots in a conidial suspension, which was adjusted to 1x106 conidia/ml for five minutes. The evaluation was performed using a scale of nine grades that represent the severity of the disease: 1 – absence of symptoms and 9 – over 75% of foliage with wilt symptoms. Data were submitted to analysis of variance and Scott-Knott test for both environments. The area under the disease progress curve (AUDPC) and genetic parameters were estimated for controlled environment tests. Significant differences were observed for crops and for controlled environment trials, indicating that environment influences directly the severity of the disease. Highly significant differences were found for lines in all environments evaluated, demonstrating the existence of genetic variability, which allows the selection of resistant lines resistant to fusarium wilt. Treatments were classified in different groups according to the Scott-knott test. When considering the lowest averages in field, controlled environment and AUDPC, the strains Ouro Branco x CNFP 10132.140, Ouro Branco x CNFP 10132.49, Ouro Branco x CNFP 10132.12, Ouro Branco x CNFP 10132.90 and Ouro Branco x CNFP 10132.48 were prominent and are candidates to produce a breeding program. Heritability estimates were high for all environments, mean of 85.48% for field and 95.47% for controlled environment. Therefore, selection for resistance to F. oxysporum f. sp. phaseoli of these lines, will be successful. In the second study it was extracted DNA from 92 lines and from genitors for genotyping with SSRs and SNPs. In order to obtain the localization of these markers, sequences of the primers were aligned to the andean genome of the common bean. The method of single marker (analysis of QTLs based on linear regression) was used to identify QTLs associated with fusarium wilt resistance. These markers were considered significant when brought up p-value <0.05. Ninety-three markers were linked to 104 QTLs associated with fusarium wilt resistance and among these, were considered significant in more than one environment PV 115, PV 251, BARC-PV-0004089, BARC-PV-0004548, BARC-PV-0003450, BARC-PV-0006051, BARC-PV-0003368 , BARC-PV-0005477 and BARC-PV-0004897. However only the BARC-PV-0003450 marker was highly significant in the two environment controled trials (p <0.001) and winter crop (p <0.01) and explained up to 21.5% of the phenotypic variance. Subsequently, the gene annotation was made considering the location of all markers that were significant at p <0.01 comprising 500 kb before and after the localization. 960 coded transcripts were annotated. It was observed in gene annotation that BARC-PV-0003450 marker is located on the chromosome 8, 338.54 kb distant of the gene Phvul.008G014700 which is associated with the putative protein RPP13 related to disease resistance, identified in Arabidopsis thaliana. This protein belongs to the third class of resistance genes that encloses the domain called Leucine-Rich Repeats (LRR). This domain is involved in the recognition of the pathogen by the host during the infection process. Therefore, this marker is suitable for marker- assisted selection aiming the development of cultivars resistant to fusarium wilt.