Root colonization and interaction among growth promoting rhizobacteria isolates and eucalypts species

Abstract

This work aimed to evaluate root colonization and interaction among isolates of rhizobacteria and eucalypt species. The method used to evaluate "in vitro" root colonization was able to indicate if the effect was benefic or deleterious allowing to pre-select isolates as potential growth promoter. There was interaction among isolates of rhizobacteria and Eucalyptus species for seed germinating and seedling growth. MF2 (Pseudomonas sp.) was the best rhizobacteria isolate for growth promotion of E. cloeziana e E. grandis. S1 (Bacillus subtilis) was the most effective for E. globulus, and Ca (Pseudomonas fulva), MF2 (Pseudomonas sp.), CIIb (Stenotrophomonas maltophilia) and S2 (B. subtilis) were the most promising isolates for the E. urophylla.RESUMO -O presente trabalho teve como objetivos avaliar a colonização de raízes e a interação entre isolados de rizobactérias e espécies de eucalipto. O método de avaliação da colonização de raízes "in vitro" possibilitou determinar o efeito benéfico ou deletério, permitindo uma pré-seleção de isolados potencialmente promotores de crescimento. Constatou-se interação entre isolados de rizobactérias e espécies de Eucalyptus em relação à germinação de sementes e o crescimento de mudas. MF2 (Pseudomonas sp.) foi o melhor isolado de rizobactéria para promoção de crescimento de E. cloeziana e E. grandis. Para E. globulus, destacou-se o S1 (Bacillus subtilis). Para E. urophylla, os isolados mais promissores foram Ca (Pseudomonas fulva), MF2 (Pseudomonas sp.), CIIb (Stenotrophomonas maltophilia) e S2 (B. subtilis).

Effect of Hydropriming and Biopriming on Seed Germination and Growth of Two Mexican Fir Tree Species in Danger of Extinction

“…Possible mechanisms include production of plant and tree hormones, an increase in the availability of nutrients, as well as biological control due to the production of antibiotics and/or siderophores [61,62]. PGPR bacteria are able to promote the growth and biomass production in different plant species, including pines [63]. In this regard, one study in particular points out that some species of Pseudomonas spp.…”

Effect of priming and seed-coating when associated with Bacillus subtilis in maize seeds

“…Correa, Bettiol and Sutton (2010) applying the formulation of Bacillus subtilis in nutrient solution to lettuce infected by Pythium spp., observed a greater accumulation of mass in the plants, and Mafia et al (2007) and Mafia et al (2009) The application of Bacillus subtilis associated with water restriction (T2) and combined with film coating (T4) favoured the growth and development of seedlings, resulting in a greater number of leaves (Table 4). The increase in the speed of emergence index (SEI) was conditional on the adoption of micropriming techniques with water restriction and film coating, both isolated and in combination; when these techniques were not adopted, B. subtilis did not display its potential, being similar to the control.…”

“…However, the treatments did not affect seed germination under those conditions ideal for the growth of microorganisms. Mafia et al (2009) (2) Significant effect by the F testa t a 5% level of significance. ns Not significant;…”

Antifungal Activity and Genetic Diversity of Selected Endophytic Fluorescent Pseudomonads

“…This delay may be due to either preliminary induced systemic resistance (Van loon et al, 1998) or preliminary colonization which suppress pathogen onset directly via different mechanisms such as production of antibiotics and volatile compound competition for space or nutrition (Mafia et al, 2009).…”