Effect of Bacillus spp. and Brevibacillus sp. on the Photosynthesis and Redox Status of Solanum lycopersicum

Plant-growth-promoting bacteria (PGPB) are gaining attention as a sustainable alternative to current agrochemicals. This study evaluated the impact of three Bacillus spp. (5PB1, 1PB1, FV46) and one Brevibacillus sp. (C9F) on important crop tomato (Solanum lycopersicum) using model cv. ‘MicroTom’. The effects these isolates were assessed (a) seedlings’ growth vigor, (b) adult potted plants. In plants, several photosynthetic parameters (chlorophylls (a b), carotenoids anthocyanins contents, transpiration rate, stomatal conductance, net CO2 intercellular concentration, chlorophyll fluorescence yields light- dark-adapted leaves)), well soluble sugars starch quantified. Additionally, redox status evaluated. While seedlings was, overall, not influenced by strains, some observed safensis FV46 stimulated content pigments, compared C9F. zhangzhouensis 5PB1 increased levels was positively correlated with photophosphorylation gas exchange phases. Interestingly, megaterium 1PB1 decreased superoxide (O2?) content, B. promoted non-enzymatic antioxidant defenses, increasing total phenol levels. These results, conducted cultivar, support theory that differently act plant physiology, their activity depends age plant, may influence photosynthesis. It would now be interesting analyze commercial cultivars.