Isolation and Characterization of Plant Growth-Promotion Diazotrophic Endophytic Bacteria Associated to Sugarcane (Saccharum officinarum L.) Grown in Paraíba, Brazil

• Published in: Brazilian Archives of Biology and Technology Vol. 65
• Main Authors: Antunes, Jadson Emanuel Lopes, Freitas, Ana Dolores Santiago de, Bonifacio, Aurenivia, Oliveira, Louise Melo de Souza, Santos, Carolina Etienne de Rosália e Silva, Lyra, Maria do Carmo Catanho Pereira de, Oliveira, José de Paula, Ollero, Francisco Javier, Araújo, Ademir Sérgio Ferreira de, Figueiredo, Marcia do Vale Barreto
• Format: Journal Article
• Language: English
• Published: Instituto de Tecnologia do Paraná (Tecpar) 01.01.2022
• Subjects: catalase; indol 3-acetic acid; Nitrogen-fixing bacteria; phosphate; phytohormones; protease
• ISSN: 1516-8913; 1678-4324
• DOI: 10.1590/1678-4324-2022200439

Sugarcane is an important Brazilian commodity, being usually cultivated in soils with low natural fertility. This study aimed to isolate diazotrophic endophytes from sugarcane tissues and evaluate the morphological and physiological characteristics of their colonies as well as their plant growth-promoting (PGP) traits in select diazotrophic endophytic bacteria. Fifty-six bacterial isolates were identified in the sugarcane tissues, and these isolates presented distinct morphological and physiological traits. A total of thirty-five bacterial isolates were biochemically evaluated. Overall, Bacillus was the dominant genus. Isolates of Methylobacterium spp. and Brevibacillus agri were present only in leaves, while Herbaspirillum seropedicae occurred only in stems. Except to IPA-CF45A, all isolates were nitrogenase positive. All endophytes exhibit production of indol 3-acetic acid. Over 50% of endophytes solubilize phosphate, release N-acyl homoserine lactones, and present the activity of 1-aminocyclopropane-1-carboxylic acid deaminase, catalase, lipase and protease. The network analysis showed that isolates belonged to Burkholderia, Herbaspirillum, and Methylobacterium interact with Bacillus. Bacterial endophytes exhibited distinct morphological, physiological, and PGP traits that are useful for sustainable agriculture, highlighting the isolates IPA-CC33, IPA-CF65, IPA-CC9 and IPA-CF27. Further studies on the effects of these diazotrophic endophytes and their potential for providing microbial inoculants for improving sugarcane fields will provide valuable information to maintain the sustainability and environment quality.