Objetivou-se, com esse estudo, isolar e selecionar rizobactérias autóctones de arroz, com potencial para o controle in vitro de Pyricularia grisea, para o controle de fungos veiculados por sementes e para a promoção de crescimento em plântulas de arroz. Para isso, foram isoladas 18 rizobactérias autóctones de arroz, as quais foram submetidas ao teste de antibiose in vitro, em que se avaliou o índice de velocidade de crescimento micelial e o percentual de inibição de crescimento micelial. No tratamento de sementes com rizobactérias, as sementes foram bacterizadas e, posteriormente, avaliou-se a qualidade sanitária (incidência de fungos), a qualidade fisiológica (vigor, germinação e índice de velocidade de germinação de sementes) e a promoção de crescimento das plântulas. No teste de antibiose, todos os isolados apresentaram potencial de antagonismo frente à P. grisea. Houve melhorias na qualidade sanitária das sementes de arroz. Contudo, os isolados não apresentaram efeito positivo sobre a qualidade fisiológica das sementes. Três isolados induziram os maiores incrementos de parte aérea e raiz de plântulas de arroz na promoção de crescimento. Assim, conclui-se que as rizobactérias testadas apresentaram potencial de controle in vitro de fungos, em especial a P. grisea, e também para promoção de crescimento de plântulas de arroz.
The aim of this study was to determine the effects of type of substrate and expanded polystyrene trays on the production of snapdragon seedlings. The experiment was completely randomized with a 3 x 2 factorial design (substrates x number of tray cells) and four replications. 'Baixa Sortida' snapdragon seeds, commercial substrate A (rice husk + vermiculite), commercial substrate B (Sphagnum + torrefied rice straw + perlite), A + B mixture (1:1) and expanded polystyrene trays with 72 and 128 cells were used. The characteristics evaluated were plant emergence rate, percentage of plant emergence at 14, 21, 28 and 35 days, number of leaves at 44 and 58 days after sowing, shoot height, root length and plant dry matter. The results showed that the substrates directly influenced the production of snapdragon seedlings. Seedling emergence and seedling development is favored by the mixture of the substrates A and B (1:1) as well as by the use of expanded polystyrene trays with 72 cells due to the higher volume available to the seedling.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.