A Novel Interaction between Plant-Beneficial Rhizobacteria and Roots: Colonization Induces Corn Resistance against the Root Herbivore Diabrotica speciosa

Author(s)

Santos, Franciele ^[1] ; Penaflor, Maria Fernanda G. V. ^[1] ; Pare, Paul W. ^{[2, 3]} ; Sanches, Patricia A. ^[1] ; Kamiya, Aline C. ^[1] ; Tonelli, Mateus ^{[1, 4]} ; Nardi, Cristiane ^[4] ; Bento, Jose Mauricio S. ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Entomol & Acarol, Escola Super Agr Luiz de Queiroz, Piracicaba, SP - Brazil

^[2] Texas Tech Univ, Dept Chem, Lubbock, TX 79409 - USA

^[3] Texas Tech Univ, Dept Biol, Lubbock, TX 79409 - USA

^[4] Mid West State Univ, Dept Agron, Guarapuava, PR - Brazil

• Document type: Journal article
• Source: PLoS One; v. 9, n. 11 NOV 18 2014.
• Web of Science Citations: 17

Abstract

A number of soil-borne microorganisms, such as mycorrhizal fungi and rhizobacteria, establish mutualistic interactions with plants, which can indirectly affect other organisms. Knowledge of the plant-mediated effects of mutualistic microorganisms is limited to aboveground insects, whereas there is little understanding of what role beneficial soil bacteria may play in plant defense against root herbivory. Here, we establish that colonization by the beneficial rhizobacterium Azospirillum brasilense affects the host selection and performance of the insect Diabrotica speciosa. Root larvae preferentially orient toward the roots of non-inoculated plants versus inoculated roots and gain less weight when feeding on inoculated plants. As inoculation by A. brasilense induces higher emissions of (E)-beta-caryophyllene compared with non-inoculated plants, it is plausible that the non-preference of D. speciosa for inoculated plants is related to this sesquiterpene, which is well known to mediate belowground insect-plant interactions. To the best of our knowledge, this is the first study showing that a beneficial rhizobacterium inoculant indirectly alters belowground plant-insect interactions. The role of A. brasilense as part of an integrative pest management (IPM) program for the protection of corn against the South American corn rootworm, D. speciosa, is considered. (AU)

• FAPESP's process: 12/12252-1 - Effect of multiple herbivory and red rot infection on induced resistance mechanisms of sugarcane
• Grantee: Maria Fernanda Gomes Villalba Peñaflor
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 08/57701-2 - Technological bases for identification, synthesis and use of semiochemicals in agriculture
• Grantee: José Roberto Postali Parra
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 13/11993-0 - Effect of jasmonic acid on sugarcane induced defenses against Diatraea saccharalis Fabricius (Lepidoptera: Crambidae) herbivory
• Grantee: Patricia Alessandra Sanches
• Support Opportunities: Scholarships in Brazil - Scientific Initiation