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The use of chemical defensives to control fungal diseases has by consequence to impact negatively over the environment and human health, this way, the use of plant extracts with antifungal properties along with proper cultural management makes viable an alternative plant production control, specially for familiar and organic cultures. The objective of this study was to perform phytochemical and antioxidant analysis of Byrsonima crassifolia (canjiqueira) barks and evaluate its antifungal potential over Fusarium solani and Sclerotinia sclerotiorum mycelial growth. The ethanol extract from plants collected in Pantanal, Mato Grosso do Sul, Brazil was submitted to phytochemical prospection, total phenol and flavonoids quantification and antioxidant activiy determination (DPPH). To evaluate antifungal activity concentrations of 800, 1200, 1600, 2000 and 2400 µg 100 mL -1 of ethanol extract were used. Which concentration was separately incorporated in agar (PDA) and shed in Petri dishes, followed by the fungi mycelial disc where the colonies diameter was measured daily. Negatives control with agar without extract and agar with an ethanol solution were used. The B. crassifolia ethanol extract presented inhibitory activity over the fungi studied where concentrations of 800 and 1600 µg 100 mL -1 , inhibited 38% of the mycelial growth of F. solani; to S. sclerotiorum the best concentration was 2400 µg 100 mL 1 , reducing 37.5%. The antifungal bark extract potential of this specie is attributed to phenolic compounds and to triterpenes derivatives.

-Isolates of Pseudomonas veronii (DFs513), Bacillus spp. (DFs093 and DFs348), Bacillus cereus (DFs769), Rodhococcus fascians (DFs843 and DFs912) and Pseudomonas fluorescens (DFs831 and DFs842), selected for Xanthomonas axonopodis pv. phaseoli control, and a combination of some of these bacteria isolates, were evaluated for possible influence on Colletotrichum lindemuthianum transmission from naturally infected and/or infested bean seeds to seedlings. In the first trial, using the paper roll method, seeds were sown in eight replications of 25 seeds that were incubated at 20 ± 2°C. Germination percentage and pathogen incidence were evaluated. In the second trial, pathogen transmission to seedlings was evaluated in sterile substratum and incubated for 10 days. Daily emerged seedlings, pathogen incidence, leaf and root dry mass were

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Resumo -O objetivo deste trabalho foi avaliar a compatibilidade entre rizobactérias biocontroladoras pré-selecionadas e o efeito de suas combinações sobre a queima-das-bainhas (Rhizoctonia solani), a meloidoginose (Meloidogyne graminicola) e a promoção de crescimento de plantas de arroz. A compatibilidade foi determinada pela antibiose. O efeito das combinações de isolados foi avaliado por microbiolização de sementes de arroz, cultivar El Paso L144, com suspensões das rizobactérias DFs185 (Pseudomonas synxantha), DFs223 (P. fluorescens), DFs306 (ainda não identificada), DFs416 e DFs418 (Bacillus sp. Biocontrol of sheath blight and root-knot nematode and growth promotion of rice plants by rhizobacteriaAbstract -The objective of this work was to evaluate the compatibility between previously selected biocontroller rhizobacteria and the effect of their combination upon sheath blight (Rhizoctonia solani), root-knot nematode (Meloidogyne graminicola) and growth promotion in rice plants. The compatibility between these bacteria was determined by the overlay antibiosis. The effect of isolate combinations was evaluated by seed microbiolization of the rice cultivar El Paso L144 with rhizobacteria suspensions of DFs185 (Pseudomonas synxantha), DFs223 (P. fluorescens), DFs306 (unidentified), DFs416 and DFs418 (Bacillus sp.). These rhizobacteria were used alone or combined in arrangements of two, three and four isolates. The DFs223 isolate was not combined because it is incompatible with the other bacteria. Five rhizobacteria combinations (DFs185/418, DFs306/416, DFs306/418, DFs416/418, DFs185/306/418) and the isolate DFs306 stood out for reducing M. graminicola reproduction and promoting plant growth. Combination DFs185/306 presented the best results for the control of R. solani and for growth promotion. The DFs306/416 combination provided the best results for the control of the two diseases.Index terms: Meloidogyne graminicola, Rhizoctonia solani, biological control, seed microbilization, growth-promoting rhizobacteria. IntroduçãoVários microrganismos podem associar-se patogenicamente às plantas de arroz (Oryza sativa L.) e causar lesões na parte aérea e radicular, levando à redução da produção (Nunes et al., 2004 A queima-das-bainhas no arroz, causada por R. solani, ocorre em áreas temperadas e tropicais. Alguns fatores têm agravado sua incidência e severidade, como a utilização excessiva de adubação nitrogenada, alta densidade de plantas e plantio de cultivares de ciclo precoce, de baixa estatura, alto perfilhamento e de maior suscetibilidade. O cultivo do arroz sucedido por hospedeiros desse fungo leva à continuidade do ciclo do patógeno e ao aumento de inóculo (Nunes et al., 2004).

-Bipolaris oryzae and Gerlachia oryzae, which cause rice brown spot and leaf scald, respectively, are mainly disseminated by seeds. The aim of this study was to evaluate the potential of seeds microbiolization to reduce transmission of these pathogens to seedlings by using the bacteria DFs185 (Pseudomonas synxantha), DFs223 (P. fluorescens), DFs306 (unidentified) and DFs418 (Bacillus sp.). Seeds naturally infested/infected with both pathogens were immersed in suspension of these bacteria (A 540 = 0.5) individually or in saline solution (control treatment). After 30 minutes of agitation at 10 °C, 400 seeds were submitted to a sanity test through the blotter method and the isolate DFs223 was the best to reduce the incidence of B. oryzae and G. oryzae in both seed lots evaluated. Seeds treated like above were sowed in sterilized vermiculite. Seed transmission and growth promotion were recorded after 21 days of incubation in the same conditions. The isolates DFs185 and DFs306 reduced transmission of both pathogens, although the isolate DFs306 was the one wich gave the greatest growth increases. The evaluation of the in vitro antibiosis showed that isolates inhibited the mycelial growth of both pathogens, except DFs306. It is possible to affirm that these bacteria have the potential to be used as a seed treatment for seed-borne disease control.Index terms: biological control, rice brown spot, rice leaf scald, seed treatment, Oryza sativa L. Biocontrole e transmissão de Bipolaris oryzae eGerlachia oryzae para plântulas de arroz RESUMO -Bipolaris oryzae e Gerlachia oryzae causadores, respectivamente, da mancha parda e da escaldadura do arroz são principalmente disseminados por sementes. Objetivou-se com esse trabalho avaliar o potencial da microbiolização de sementes para a redução da transmissão destes patógenos das sementes para as plântulas usando as bactérias DFs185 (Pseudomonas synxantha), DFs223 (P. fluorescens), DFs306 (não identificado) e DFs418 (Bacillus sp. Termos para indexação: controle biológico, mancha parda do arroz, escaldadura do arroz, tratamento de sementes, Oryza sativa.

Objetivou-se avaliar repostas da Avena sativa L. à inoculação, com isolados de Bacillus subtilis e B. megaterium. O experimento foi conduzido em solo classificado como Latossolo Vermelho distrófico no município de Campo Grande, MS. Os tratamentos foram constituídos de cinco doses de inoculante (0, 50, 100, 150, 200 mL) aplicados no sulco de plantio, sendo distribuídos em parcelas experimentais, com as dimensões de 3,0 m x 4,0 m, segundo delineamento em blocos ao acaso com quatro repetições. Foram avaliados os parâmetros biométricos da planta diâmetro do perfilho e quantidade de perfilho, produção de biomassa fresca e seca da parte aérea, produção de grãos. Na qualidade do produto avaliou-se a bromatologia e os teores de minerais da folha bandeira. As plantas de aveia, apresentaram aumento na taxa de crescimento (TC), diâmetro de perfilho (DP), teores foliar de N, Fe e Cu, proteína bruta (PB), fibra detergente neutro (FDN). A aveia teve seu desempenho favorecido com as doses de inoculante até 125 mL. Observou-se, também, aumento da concentração de proteína na planta de forma concentração-resposta. Conclui-se que, o inoculante à base dos dois isolados das bactérias utilizadas no sulco de plantio, beneficia a produção de aveia.