Isolation, characterization and plant growth promotion effects of putative bacterial endophytes associated with sweet sorghum (Sorghum bicolor (L) Moench)

Identification and characterization of the part of the bacterial community associated with field-grown tall fescue (Festuca arundinacea) cv. SFRO Don Tomás in Uruguay

“…However, the initial plant material which we collected for bacterial isolation had no disease symptoms, which is an essential prerequisite for endophytic bacteria (Hallmann et al 1997;Rosenblueth and Martínez-Romero 2006). Within the Gammaproteobacteria, isolates of the genera Pantoea, Acinetobacter, Rhanella and Pseudomonas have been previously reported as being associated with and/or endophytic within several poaceous plants, including sweet sorghum (Sorghum bicolor), sugarcane (Saccharum officinarum), maize (Zea mays), rice (Oryza sativa), grapevine (Vitis vinifera), canola (Brassica napus) and others (Bell et al 1995;Misko and Germida 2002;Hallmann and Berg 2006;Rosenblueth and Martínez-Romero 2006;Taulé et al 2012;Mareque et al 2015). Of particular significance is that Pseudomonas and Rhanella isolates have been previously reported as being associated with tall fescue (Monk et al 2009).…”

“…Pantoea spp. have been reported to be PGPB of several important agronomical crops, such as maize, rice, sugarcane, sweet sorghum, canola, lentil (Lens culinaris) and pea (Pisum sativum) (Verma et al 2001;Sergeeva et al 2007;Montañez et al 2012;Taulé et al 2012;Quecine et al 2012;Mareque et al 2015). Pseudomonas spp.…”

“…The soil profiles of sites A and B were as follows: A (pH 5.7, 13 % sand, 54 % silt, 33 % clay, 2.5 % organic matter, total N 0.28 %), B (pH 5.8, 30 % sand, 67 % silt, 13 % clay, 2.9 % organic matter, total N 0.55 %). The protocol employed for bacterial isolation was as reported by Mareque et al (2015) with slight modifications in the incubation times and the culture media employed. Seeds and plant tissues (root and stems) were surface-disinfected by incubation in 5 % HClO 4 for 45 min and in 4 % HClO 4 for 15 min, respectively.…”

“…The final reaction mixture (25 μl) consisted of 2.5 μl 10X Taq reaction buffer (Fermentas, Thermo Fisher Scientific, Waltham, MA) 3.0 mM MgCl 2 , 0.16 mM dNTPs, 0.8 μM of both set of primers, 0.5 U Taq polymerase (Fermentas), 4 % bovine serum albumin and 4.0 μl of a cell lysate template and was amplified as described by Taulé et al (2012) and Mareque et al (2015). The ability to fix N 2 was also tested in those isolates, which harbored the nifH gene, in vials containing LGI and NFCC, N-free semisolid media (Reis et al 1994;Mirza and Rodrigues 2012).…”

Induction of drought tolerance by inoculation of Bacillus aryabhattai on sugarcane seedlings

“…These phytohormones alter the architecture of the root system, morphoanatomically, by promoting the absorbent and adjacent roots; consequently, intensifying the absorption of mineral resources that condition plant growth and development. The other notable direct and indirect benefits include solubilization of nitrates, phosphates, Ca, Mg, Zn, and Si, making them readily assimilable for functional roots; biofixation of atmospheric N 2 ; symbiotic association to arbuscular mycorrhizal fungi, which is very important to the interception of P, a mineral element practically immobile in soil solution; stimulation of the biosynthesis of jasmonic and salicylic acids, which are fundamental to the phytohormonal signaling of precursor routes of secondary metabolites for the synthesis of antimicrobial compounds, including alkaloids, aldehydes, phenols and phytoalexins, and antioxidant enzymes that are sequesters of reactive oxygen species; and biocontrol of potential phytopathogens by the synthesis of antibiotics and interspecific competition for rhizosphere niches and substrates vital to microbial metabolism (Schmidt et al, 2014;Cherif et al, 2015;Mareque et al, 2015).…”