Isolation and characterization of potential plant growth-promoting bacteria from sugarcane

CLAPS P; CINÀ, P; CASTAGNARO AP.; RACEDO J; ALIBRANDI, P; WELIN B.; MICHAVILA G; CIACCIO, M; GALLO, G

San Miguel de Tucumán

Congreso; XXX International Society of Sugarcane Technologists Congress; 2019

ISSCT

The inappropriate use of agrochemicals to improve crop production can be hazardous for both the environment and human/animal health. It is therefore of great interest to develop effective and more environmental-friendly crop-management alternatives, such as the use of plant growth-promoting bacteria (PGPB). PGPB can enhance plant growth and protect plants from biotic and abiotic stresses. In general, biological-control mechanisms and plant-growth promotion by PGPB are based on microbial metabolites that can adversely affect the pathogen, induce systemic resistance in the plant and/or improve plant growth. The aim of this work was to isolate PGPB from sugarcane roots, stalks, and rhizosphere that potentially could promote plant growth and generate stress protection. Biochemical markers associated with growth promotion and microbial antagonism of the bacterial isolates, i.e. siderophore production, synthesis of indole acetic acid (IAA), phosphate solubilization and antibiotic production, were studied. I n addition, isolates were taxonomically characterized by sequence comparison of the 16S rRNA coding DNA. A total of 32 strains were isolated exhibiting a variable capacity of producing IAA and siderophores, phosphate solubilization, nitrogen-fixation, antibiotic production and tolerance to salt and water stress. These isolates belong to several bacterial genera and revealed a great bacterial diversity. Several isolates showed important plant-growth promoting abilities, indicating their usefulness in development of bioinoculants intended for sugarcane management.