Cultivable bacterial microbiota of roots, stalks and rhizosphere of Saccharum officinarum: a new reservoir of plant growth-promoting bacteria (PGPB)?

CINÀ, P; ALIBRANDI, P; SIINO, D; LO MONACO, N; MICHAVILA, G; FILIPPONE, MP; CASTAGNARO, AP; RACEDO, J; GALLO, G; CIACCIO, M; PUGLIA, AM

Palermo

Congreso; IBIM-CNR V° Meeting "Biotecnologie: ricerca di base, interdisciplinare e traslazionale in ambito biomedico"; 2018

Microorganisms are widespread inhabitants of rhizosphere and plant tissues and have been shown to assist plant growth and health. However, studies evaluating the diversity, structure and impact of the microbiota in economic important crops are still rare. Modern sugarcane varieties are allopolyploid hybrids, principally derived from crossings between plants of Saccharum officinarum and S. Spontaneum, resulting from more than 150 years of genetic improvement. Sugarcane is produced in tropical and subtropical regions and has been the most important cultivar in the Province of Tucuman, Argentina for over a century. Due to the socio-economic importance of sugarcane production, in Tucumán, the Estación Experimental Agroindustrial Obispo Colombres (EEAOC) developed an important breeding program over 50 years ago that has been responsible for the release of all sugarcane cultivars in the Province for the last decades, among which the variety LCP 85-384 has been one of the most successful.In this work, we aimed to isolate, identify and characterize bacteria isolated from roots, stalks, and rhizosphere of LCP 85-384, where the long term goal is to increase the agronomy, environmental and social sustainability of this important food and energy crop.A total of thirty-two strains were isolated from roots, stalks and rhizosphere of sugarcane variety LCP 85-384, which were taxonomically characterized by sequence comparison of their 16S rRNA gene. Furthermore, plant growth-promoting (PGP) properties of all the strains identified were assayed. The isolated strains differentially produced indole acetic acid (IAA) and siderophores. Moreover, they exhibited a variable capacity for phosphate solubilizations, nitrogen-fixing, antibiotic productions and resistance to water and salt stress.