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Identification of Fusarium isolates in a sample at the species level is an important and difficult task because many Fusarium species have similar morphological characteristics. The phylogenetic relations of species have been applied in Fusarium systematic and may solve taxonomic difficulties. The aim of the present study is to characterize pathogeny of Fusarium isolates through morphological analysis (concept of morphological species) associated with symptoms in hosts together with phylogeny analysis (concept of phylogenetic species) using internal transcribed spacer region (ITS) of ribosomal DNA for species identification. For the morphological characterization, Fusarium isolates were grown in PDA culture medium. Then, they were classified based on colony color and the microconidial, macroconidial and chlamydospore structures. The isolates were characterized molecularly by amplifying and sequencing the ITS region of the ribosomal DNA. The sequences generated were compared with those placed in the Genbank and Maximum Likelihood phylogenetic trees were constructed. Out of 14 isolates characterized morphologically and molecularly, five isolates were grouped in the Gibberella fujikuroi species complex in the Liseola section, seven presented characteristics of species from the Elegans section within the F. oxysporum species complex and two isolates presented characteristics of the section Gibbosum species complex in the F. incarnatum-equiseti species complex. Thus, seven isolates (section Elegans) belonged to the species F. oxysporum, two isolates (section Gibbosum) to the species F. equiseti. However, the ITS region of the ribosomal DNA did not provide sufficient evidence to define the species of G. fujikuroi species

The objective of the present study was to assess the seed health quality, quantification of seed-seedling pathogen transmission and the effect of plant extracts in reducing plant pathogens in the seeds of the tomato varieties San Marzano and Ipa 6. For the seed health, the samples were disinfested, plated and assessed after seven days, according to the Brazilian Seed Analysis Rule. For the transmission rate, 12 trays were prepared with 100 seeds each and assessed at 7, 14 and 21 d.a.s. (days after seeding) using 100 seedlings. The plant (main root, stalk and leaves) tissues were plated in PDA culture medium and assessed after seven days of incubation. Aqueous extracts were prepared from cinnamon, basil, neem and eucalyptus with 0.5% concentration and the seeds were immersed in each solution for 10 minutes. Then, they plated and assessed after seven days. The health test showed that biggest incidences of Aspergillus fumigatus (26 %) and Aspergillus flavus (26 %) were occurred in the seeds of the varieties Ipa 6 and San Marzano, respectively. The fungi A. flavus, A. fumigatus, A. niger, R. stolonifer and Curvularia sp. were detected in quantification of transmission in the seeds of the two tomato varieties. The treatment with basil extract resulted in the least fungus incidence in the transmission quantification of ‘San Marzano’ tomato seeds, while on Ipa 6 seeds the eucalyptus treatment performed better. The interference of treatments was not observed in tomato seed germination. However, there was decrease in incident of pathogens in seeds treated with the plant extracts and different effects was observed based on type and species of the pathogen.

The objective of the present study was to assess the anti-fungal activity of medicinal plant extracts on inhibition of Colletotrichum gloesporioides mycelial growth, sporulation and germination and on anthracnose control in Heliconia psitacorum cv. Golden Torch and Heliconia rostrata. Extracts of garlic, lemon grass, cinnamon, lemon balm, eucalyptus, ginger, mint, bitter melon and black pepper were used. The, mycelial were assessed in vitro by measuring their growth in Petri dishes. Sporulation was assessed by counting spores in a Neubauer chamber. Germination was observed based on germination tube emission. In the in vitro tests, the inflorescences were treated with the plant extracts and inoculated with the pathogen 24 h later. The results showed that all the extracts presented anti-fungal activity, in greater or lesser intensity, compared to the control. The garlic extract resulted in the highest mycelial growth inhibition rate. Regarding sporulation, the bitter melon, ginger, mint, popcorn eucalyptus and bitter melon extracts were more efficacious, interfering in spore formation; while the ginger extract most reduced spore germination inhibiting germination tube emission. For the in vivo tests, it was observed that all the plant extracts tested were efficient in reducing lesion severity in the inflorescence, showing that the use of plant extracts may be a promising alternative for managing the diseases that affect helconia post-harvest. Key words: Alternative control, fungi, Colletotrichum gloesporioides, tropical flowers.

Papaya target-spot, caused by fungus Corynespora cassiicola presents a wide geographic distribution, causing leaf spots in several hosts. The aim of this research was to evaluate the behavior of papaya varieties and/or selections to the natural occurrence of target spot, and test the fungi toxic effect of neem, citronella and eucalyptus extracts, and fungi static effects of Bacillus isolates on the fungus C. cassiicola in vitro. To evaluate the natural occurrence of the disease in field, symptoms on leaves of 11 papaya varieties and/or selections have been assessed. The pathogenicity of isolates was verified by inoculation of plants in greenhouse. Neem, citronella and eucalyptus extracts were prepared at concentrations of 10, 15 and 20% and poured into Petri dishes containing C. cassiicola mycelium discs. For , Bacillusnine isolates were used, and the antagonistic potential was evaluated by the pairing of pathogen and isolate colonies by the circle method. Papaya varieties and/or selections presented all leaves with injury, and Canaan Sunrise Solo and Canaan Golden selections showed the greatest number of injuries per leaf, showing that papaya varieties and/or selections respond differently to the phytopathogen. All plant extracts tested showed inhibitory effect on the mycelial growth of C. cassiicola in vitro. Bacillus isolates showed an antagonistic potential on the mycelial growth of the fungus, with B. methylotrophicus (Iso 31 and Iso 41) being the most promising as a biological control agent. The results indicate that forms of alternative control of diseases are promising in the management of papaya target-spot. RESUMO A mancha-alvo do mamoeiro, causada pelo fungo Corynespora casiicola, possui ampla distribuição geográfica, causando manchas foliares em vários hospedeiros. O objetivo desta pesquisa foi avaliar o comportamento de variedades/seleções de mamoeiro à ocorrência natural da mancha-alvo e testar o efeito fungitóxico de extratos de nim, citronela e eucalipto, e fungistático de isolados de Bacillus sobre o fungo C. cassiicola in vitro. Para avaliar a ocorrência natural da doença no campo, foram avaliados os sintomas em folhas de 11 variedades e/ou seleções de mamoeiro. A patogenicidade dos isolados foi verificada pela inoculação de plantas em casa de vegetação. Os extratos de nim, citronela e eucalipto foram preparados nas concentrações de 10; 15 e 20% e vertidos em placas de Petri, contendo discos de micélio de C. cassiicola. Para Bacilllus, foram utilizados nove isolados, e a potencialidade antagonista foi avaliada pelo pareamento de colônias do patógeno e dos isolados, pelo método de círculo. As variedades e seleções de mamoeiro apresentaram a totalidade das folhas com lesões, sendo as seleções Canaã Sunrise Solo e Canaã Golden as que apresentaram maior número de lesões/folhas, mostrando que as variedades/seleções de mamoeiro respondem diferentemente ao fitopatógeno. Todos os extratos vegetais testados apresentaram efeito inibitório sobre o crescimento micelial in vitro de C. cassiicola. Os isolados de Bacillus apresentaram potencial antagônico sobre o crescimento micelial do fungo, sendo os isolados de B. methylotrophicus (Iso 31 e Iso 41) mais promissores como agentes de controle biológico. Estes resultados indicam que formas de controle alternativo de doenças são promissoras no manejo da mancha-alvo do mamoeiro.

The fusarium is an important disease in yellow passion fruit that causes severe limitation in fruit production and reduced longevity of the orchards. This study aimed to evaluate the effect of organic residues in vitro and in vivo as alternative control in Fusarium of yellow passion fruit, caused by Fusarium oxysporum f. sp. passiflorae. Six concentrations were evaluated in vitro (0, 2, 4, 6, 8 and 10 %), in the form aqueous extracts, in the mycelial growth inhibition and in vivo (0, 20, 40, 60, 80 and 100 g kg-1), incorporated on soil for the Fusarium control. The organic residues used were eucalyptus leaves, bagasse babassu and cassava peeling. These residues were subjected to nutritional and microbiological analyzes. The pathogenicity of isolates tested was confirmed, which proves the presence of Fusarium in yellow passion fruit in vivo. Bagasse babassu presented the highest N, P and K concentration. Fungal species with higher frequency were Penicillium sp., Aspergillus niger, Aspergillus flavus and Aspergillus ochraceus. I There was a significative inhibition in vitro of the bagasse babassu extract at 6 % and other two residues at 10 %. In vivo the 60 g kg-1 of bagasse babassu and 80 g kg-1 of cassava peeling were efficient for Fusarium control. Eucalyptus leaves presented no effect on development of Fusarium wilt in yellow passion fruit in the greenhouse. The organic residues can be used for the Fusarium control in yellow passion fruit.

Este trabalho objetivou avaliar a qualidade sanitária de sementes de arroz, quantificar a transmissão de Curvularia lunata associada à semente e à plântula, e avaliar o efeito dos isolados de Bacillus spp., no controle da mancha foliar, do cultivar Bonança. Para avaliação da sanidade de sementes, as amostras foram desinfestadas e plaqueadas, sendo avaliadas após sete dias de incubação. Na confirmação da patogenicidade, as plântulas foram inoculadas por meio de pulverização e a avaliação da doença ocorreu sete dias após. Na caracterização do isolado de C. lunata, foi realizada medição da largura, comprimento e número de septos de 100 conídios. Para a taxa de transmissão de C. lunata, foram preparadas 12 bandejas, com 100 sementes cada, de modo a proceder-se às avaliações aos 7, 14, 21 dias após a semeadura (d.a.s.). De cada uma das 100 plântulas, foram separadas as raízes, após sete dias. A inoculação dos isolados de Bacillus foi realizada na forma de suspensão, pulverizada sobre a parte aérea das plântulas. Após uma semana, foi inoculado a C. lunata. A avaliação foi efetuada aos 15 dias após inoculação dos isolados patogênicos, medindo-se o tamanho da lesão. No teste de sanidade foi detectada maior incidência de C. lunata (70%), o qual se apresentou patogênico à variedade de arroz Bonança, sendo detectado em todos os órgãos da plântula. Dentre os isolados de Bacillus, os que mais se destacaram no controle foram B41 (B. Cereus) e B35 (Bacillus sp.), confirmando seu potencial biocontrolador. This study evaluates the sanitary quality of rice seeds cultivar Bonança, quantifies the transmission of Curvularia lunata associated with seeds - seedling and evaluates the efficiency of Bacillus spp. isolates for the control of leaf spot. The samples were disinfected and plated, and seed health was evaluated after seven days. After confirmation of pathogenicity, the seedlings inoculated by the spraying method and the occurrence of disease was assessed after seven days. For characterization of the C. lunata isolate, width and length measurements and number of septa of 100 conidia were taken. We assessed transmission rate of C. lunata in 12 trays, each with 100 seeds, and conducted evaluations at 7, 14, 21 days after infection. From each of the 100 seedlings we separated the primary root, the stem and glumes and plated them on PDA for evaluation after seven days. The inoculation of Bacillus isolates was carried out throughaerial spraying of the suspension on the plants. After one week, C. lunata was inoculated and after 15 days lesion dimensions were measured. We detected the highest incidence of C. lunata (70%), which was pathogenic to the rice variety Bonança and was detected in all organs of the seedling. Among the isolates of Bacillus, those that stood out in controlling C. lunata were B41 (B. Cereus) and B35 (Bacillus sp.), confirming their potential for biocontrol.

A utilização de materiais orgânicos que melhoram as características físicas, químicas e biológicas do solo vem sendo estudada como indutor da supressividade a fitopatógenos. Objetivou-se avaliar o efeito da incorporação da parte aérea de leguminosas no controle da fusariose do tomateiro. Os resíduos frescos das leguminosas leucena, feijão guandu, amendoim forrageiro e feijão de porco foram incorporados ao solo nas concentrações 0; 20; 40; 60 e 80 g L-1. Sementes de tomateiro da variedade Santa Cruz Kada Gigante foram semeadas em bandejas contendo terra autoclavado e húmus de minhoca. As mudas foram transplantadas para vasos, contendo substrato (terra autoclavada + resíduo fresco), 15 dias após a semeadura. Aos 15 dias após o transplantio realizou-se a inoculação, por meio de ferimento de raízes em meia lua, aplicando em seguida 20 mL da suspensão de 1x10(6) conídios mL-1 por planta. A avaliação foi realizada 21 dias após a inoculação através de escala de notas variando de 1 a 5. O delineamento experimental foi inteiramente casualizado, com quatro repetições, sendo a unidade experimental duas plantas por vaso. A incorporação da parte aérea das leguminosas leucena, feijão guandu, amendoim forrageiro e feijão de porco demonstrou eficiência no controle da fusariose. Maior percentual de controle foi obtido com os resíduos de amendoim forrageiro (40 g L-1), feijão de porco (60 g L-1) e leucena (80 g L-1), apresentando um percentual de controle de 73,3%. O amendoim forrageiro pode ser considerado o mais eficiente, por necessitar de uma menor concentração para atingir o mesmo percentual de controle da fusariose. The use of organic materials that improve physical, chemical and biological soil properties has been studied as inducer of suppressiveness to plant pathogens. This study aimed to evaluate the effect of incorporating legume shoot in the control of Fusarium wilt affecting tomatoes. Fresh residues of the legumes Leucaena, pigeon pea, peanut and jack bean were added to the soil at the concentrations of 0, 20, 40, 60 and 80 g L-1. Seeds from tomato plants of Santa Cruz Kada Gigante variety were sown on trays containing autoclaved soil and earthworm castings. The seedlings were transplanted to pots containing substrate (autoclaved soil + fresh residue) at 15 days after sowing. At 15 days after transplanting, inoculation was done by means of half-moon-shaped injury in the roots, followed by application of 20 mL of a suspension of 1x10(6) conidia mL-1 plant. The evaluation was carried out at 21 days after inoculation by using a visual grading scale from 1 to 5. Experimental design was completely randomized, with four replicates, and the experimental unit was constituted of two plants per pot. Incorporation of shoot of the legumes Leucaena, pigeon pea, peanut and jack bean was efficient in controlling Fusarium wilt. The highest control percentage was obtained with residues of peanut (40 g L-1), jack bean (60 g L-1) and Leucaena (80 g L-1), resulting in a control percentage of 73.3%. The peanut can be considered most efficient because it requires a lower concentration to reach the same percentage of Fusarium wilt control.

A fusariose é uma importante doença na cultura do maracujá e causa severa limitação na produção de frutos e redução da longevidade dos pomares. Objetivou-se avaliar o efeito de resíduos orgânicos in vitro e in vivo como medida alternativa no controle da fusariose do maracujazeiro, causada por Fusarium oxysporum f. sp. passiflorae. Foram avaliadas seis concentrações in vitro (0, 2, 4, 6, 8 e 10 %), na forma de extrato aquoso, na inibição do crescimento micelial e in vivo (0, 20, 40, 60, 80 e 100 g kg-1), incorporados ao solo, para o controle de Fusarium. Os resíduos orgânicos utilizados foram folhas de eucalipto, bagaço do coco babaçu e casca de mandioca. Nestes resíduos foram realizadas análises nutricionais e microbiológicas. Foi confirmada a patogenicidade dos isolados testados, o que comprova a fusariose em maracujazeiro amarelo in vivo. O bagaço do coco babaçu foi o que apresentou maiores concentrações de N, P e K. As espécies fúngicas presentes com maior frequência foram Penicillium sp., Aspergillus niger, Aspergillus flavus e Aspergillus ochraceus. In vitro o extrato de bagaço do coco babaçu obteve inibição significativa a 6 % e os extratos de folhas de eucalipto e casca de mandioca a 10 %. In vivo a concentração de 60 g kg¹ de bagaço do coco babaçu e 80 g kg¹ de casca de mandioca foram eficientes no controle da fusariose. O resíduo de eucalipto não influenciou o desenvolvimento da murcha do fusário no maracujazeiro em casa de vegetação. É possível utilizar resíduos orgânicos para o controle da fusariose em maracujazeiro amarelo. The fusarium is an important disease in yellow passion fruit that causes severe limitation in fruit production and reduced longevity of the orchards. This study aimed to evaluate the effect of organic residues in vitro and in vivo as alternative control in Fusarium of yellow passion fruit, caused by Fusarium oxysporum f. sp. passiflorae. Six concentrations were evaluated in vitro (0, 2, 4, 6, 8 and 10 %), in the form aqueous extracts, in the mycelial growth inhibition and in vivo (0, 20, 40, 60, 80 and 100 g kg-1), incorporated on soil for the Fusarium control. The organic residues used were eucalyptus leaves, bagasse babassu and cassava peeling. These residues were subjected to nutritional and microbiological analyzes. The pathogenicity of isolates tested was confirmed, which proves the presence of Fusarium in yellow passion fruit in vivo. Bagasse babassu presented the highest N, P and K concentration. Fungal species with higher frequency were Penicillium sp., Aspergillus niger, Aspergillus flavus and Aspergillus ochraceus. I There was a significative inhibition in vitro of the bagasse babassu extract at 6 % and other two residues at 10 %. In vivo the 60 g kg-1 of bagasse babassu and 80 g kg-1 of cassava peeling were efficient for Fusarium control. Eucalyptus leaves presented no effect on development of Fusarium wilt in yellow passion fruit in the greenhouse. The organic residues can be used for the Fusarium control in yellow passion fruit. La fusariosis, es una importante enfermedad en el cultivo de maracuyá que causa una severa limitación en la producción de frutos y una reducción en la longevidad del cultivo. Este trabajo tuvo como objetivo, evaluar el efecto de residuos orgánicos in vitro e in vivo como medida alternativa para el manejo de la fusariosis en el maracuyá, causada por Fusarium oxysporum f. sp. passiflorae. Se evaluaron seis concentraciones in vitro (0, 2, 4, 6, 8 y 10 %) en forma de extracto acuoso, e igual número, para la inhibición del crecimiento micelial in vivo (0, 20, 40, 60, 80, 100 g kg-1), incorporados al suelo para el control de Fusarium. Los residuos orgánicos utilizados, fueron hojas de eucalipto, bagazo de coco babasú y cáscara de yuca. Estos residuos fueron sometidos a análisis nutricionales y microbiológicos. Se confirmó la patogeneidad de los aislados evaluados, lo que comprobó la presencia de fusariosis en el maracuyá amarillo in vivo. La bagazo babasú, presentó las mayores concentraciones de N, P y K. Las especies fúngicas presentes con mayor frecuencia fueron Penicillium sp., Aspergillus niger, Aspergillus flavus y Aspergillus ochraceus. En el proceso in vitro, el extracto de babasú presento inhibición significativa en la concentración del 6 % y, en los extractos de hojas de eucalipto y cáscara de yuca la del 10 %. A nivel in vivo, la concentración de 60 g kg¹ de bagazo babasú y 80 g kg¹ de cáscara de mandioca, fueron eficientes en el control de fusariosis. El residuo de eucalipto no influenció el desarrollo de la mancha de fusarium del maracuyá en vivero. Es posible utilizar residuos orgánicos para el control de fusarium en el cultivo de maracuyá amarillo.