Biochemical and Molecular Characterization of High Population Density Bacteria Isolated from Sunflower

Natural and beneficial associations between plants and bacteria have demonstrated potential commercial application for several agricultural crops. The sunflower has acquired increasing importance in Brazilian agribusiness owing to its agronomic characteristics such as the tolerance to edaphoclimatic...

Full description

Saved in:
Bibliographic Details
Published inJournal of microbiology and biotechnology Vol. 22; no. 4; pp. 437 - 447
Main Authors Goes, Kelly Campos Guerra Pinheiro de, State University of Londrina, Rodovia Celso Garcia Cid, Campus Universitario, Londrina, Parana, Brasil, Fisher, Maria Luisa de Castro, State University of Londrina, Rodovia Celso Garcia Cid, Campus Universitario, Londrina, Parana, Brasil, Cattelan, Alexandre Jose, Embropa Soybean, Rodovia Carlos Joao Strass, Distrito de Warta, Londrina, Parana, Brasil, Nogueira, Marco Antonio, Embropa Soybean, Rodovia Carlos Joao Strass, Distrito de Warta, Londrina, Parana, Brasil, Portela de Carvalho, Claudio Guilherme, Embropa Soybean, Rodovia Carlos Joao Strass, Distrito de Warta, Londrina, Parana, Brasil, Martinez de Oliveira, Andre Luiz, State University of Londrina, Rodovia Celso Garcia Cid, Campus Universitario, Londrina, Parana, Brasil
Format Journal Article
LanguageEnglish
Published Seoul Korean Society for Applied Microbiology 01.04.2012
한국미생물·생명공학회
Subjects
Online AccessGet full text

Cover

Loading…
More Information
Summary:Natural and beneficial associations between plants and bacteria have demonstrated potential commercial application for several agricultural crops. The sunflower has acquired increasing importance in Brazilian agribusiness owing to its agronomic characteristics such as the tolerance to edaphoclimatic variations, resistance to pests and diseases, and adaptation to the implements commonly used for maize and soybean, as well as the versatility of the products and by-products obtained from its cultivation. A study of the cultivable bacteria associated with two sunflower cultivars, using classical microbiological methods, successfully obtained isolates from different plant tissues (roots, stems, florets, and rhizosphere). Out of 57 plant-growth-promoting isolates obtained, 45 were identified at the genus level and phylogenetically positioned based on 16S rRNA gene sequencing: 42 Bacillus (B. subtilis, B. cereus, B. thuringiensis, B. pumilus, B. megaterium, and Bacillus sp.) and 3 Methylobacterium komagatae. Random amplified polymorphic DNA (RAPD) analysis showed a broad diversity among the Bacillus isolates, which clustered into 2 groups with 75% similarity and 13 subgroups with 85% similarity, suggesting that the genetic distance correlated with the source of isolation. The isolates were also analyzed for certain growth-promoting activities. Auxin synthesis was widely distributed among the isolates, with values ranging from 93.34 to 1653.37 μM auxin per jug of protein. The phosphate solubilization index ranged from 1.25 to 3.89, and siderophore index varied from 1.15 to 5.25. From a total of 57 isolates, 3 showed an ability to biologically fix atmospheric nitrogen, and 7 showed antagonism against the pathogen Sclerotinia sclerotiorum. The results of biochemical characterization allowed identification of potential candidates for the development of biofertilizers targeted to the sunflower crop.
Bibliography:2013000117
A50
G704-000169.2012.22.4.003
ISSN:1017-7825
1738-8872
DOI:10.4014/jmb.1109.09007