The Multifarious Endophytic Actinobacterial Isolate, Streptomyces tubercidicus UAE1, Combined With the Seaweed Biostimulant Further Promotes Growth of Avicennia marina

Mangrove ( Avicennia marina ) is a “green lung” tree growing along the Arabian Gulf coastline in United Arab Emirates. Here, we aimed to determine impact of application commercial seaweed extract (SWE) biostimulant and endophytic actinobacterial isolates on growth performance endogenous hormonal levels mangroves. Therefore, isolated plant growth-promoting (PGP) actinobacteria (PGPA) from mangrove roots evaluated their potential as biological inoculants seedlings under greenhouse open-field nursery conditions. Seven salt-tolerant had ability produce different vitro regulators (PGRs) 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase (ACCD) solubilize phosphorus. Accordingly, only one isolate, Streptomyces tubercidicus UAE1 St ), was selected based its relative superiority displaying multiple modes action successfully colonizing tissues for 15 weeks. In experiments, plants treated with SWE significantly p < 0.05) improved dry biomass by 40.2% 55.1% 42.2% 55.4% shoots, respectively, compared seawater-irrigated non-treated (control). However, +SWE caused greater significant increase weight (67.6%) shoots (65.7%) than did control plants. Following combined treatment +SWE, planta PGR were found be greatly enhanced over grown non-SWE supplemented sediments, or inoculated without supplementation SWE, non-inoculated sediments supplied only. This evident increases photosynthetic pigments production PGRs, well reduction ACC those other treatments. Tissue nutrient contents also increased at least two-fold control. Similar effects observed all parameters natural Combining not stimulates but potentially has additive ecosystem productivity nutrient-impoverished soils coastal areas. report first field marine agriculture that uses base capable producing PGRs ACCD.