Next Article in Journal / Special Issue
Host Plant Specific Control of 2,4-Diacetylphloroglucinol Production in the Rhizosphere
Previous Article in Journal / Special Issue
Initial Steps towards Biocontrol in Hops: Successful Colonization and Plant Growth Promotion by Four Bacterial Biocontrol Agents
Open AccessArticle

Bacillus simplex—A Little Known PGPB with Anti-Fungal Activity—Alters Pea Legume Root Architecture and Nodule Morphology When Coinoculated with Rhizobium leguminosarum bv. viciae

1
Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA 90095-1606, USA
2
School of Biological Sciences, University of Waikato, Hamilton 3240, New Zealand
3
Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, CA 90095-1489, USA
4
Department of Botany and Plant Sciences, University of California, Riverside, CA 91521, USA
5
Molecular Biology Institute, University of California, Los Angeles, CA 90095-1570, USA
*
Author to whom correspondence should be addressed.
These authors contributed equally to this work.
Agronomy 2013, 3(4), 595-620; https://doi.org/10.3390/agronomy3040595
Received: 21 June 2013 / Revised: 29 August 2013 / Accepted: 13 September 2013 / Published: 26 September 2013
Two strains, 30N-5 and 30VD-1, identified as Bacillus simplex and B. subtilis, were isolated from the rhizospheres of two different plants, a Podocarpus and a palm, respectively, growing in the University of California, Los Angeles (UCLA) Mildred E. Mathias Botanical Garden. B. subtilis is a well-known plant-growth promoting bacterial species, but B. simplex is not. B. simplex 30N-5 was initially isolated on a nitrogen-free medium, but no evidence for nitrogen fixation was found. Nevertheless, pea plants inoculated with B. simplex showed a change in root architecture due to the emergence of more lateral roots. When Pisum sativum carrying a DR5::GUSA construct, an indicator for auxin response, was inoculated with either B. simplex 30N-5 or its symbiont Rhizobium leguminosarum bv. viciae 128C53, GUS expression in the roots was increased over the uninoculated controls. Moreover, when pea roots were coinoculated with either B. simplex 30N-5 or B. subtilis 30VD-1 and R. leguminosarum bv. viciae 128C53, the nodules were larger, clustered, and developed more highly branched vascular bundles. Besides producing siderophores and solubilizing phosphate, the two Bacillus spp., especially strain 30VD-1, exhibited anti-fungal activity towards Fusarium. Our data show that combining nodulating, nitrogen-fixing rhizobia with growth-promoting bacteria enhances plant development and strongly supports a coinoculation strategy to improve nitrogen fixation, increase biomass, and establish greater resistance to fungal disease. View Full-Text
Keywords: anti-fungal activity; lateral roots; nodulation; plant growth-promoting bacteria; phosphate solubilization; siderophores anti-fungal activity; lateral roots; nodulation; plant growth-promoting bacteria; phosphate solubilization; siderophores
Show Figures

Figure 1

MDPI and ACS Style

Schwartz, A.R.; Ortiz, I.; Maymon, M.; Herbold, C.W.; Fujishige, N.A.; Vijanderan, J.A.; Villella, W.; Hanamoto, K.; Diener, A.; Sanders, E.R.; DeMason, D.A.; Hirsch, A.M. Bacillus simplex—A Little Known PGPB with Anti-Fungal Activity—Alters Pea Legume Root Architecture and Nodule Morphology When Coinoculated with Rhizobium leguminosarum bv. viciae. Agronomy 2013, 3, 595-620.

Show more citation formats Show less citations formats

Article Access Map by Country/Region

1
Only visits after 24 November 2015 are recorded.
Search more from Scilit
 
Search
Back to TopTop