Navigation Links
Scientists identify bacteria that increase plant growth
Date:1/26/2009

UPTON, NY Through work originally designed to remove contaminants from soil, scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory and their Belgium colleagues at Hasselt University have identified plant-associated microbes that can improve plant growth on marginal land. The findings, published in the February 1, 2009 issue of Applied and Environmental Microbiology, may help scientists design strategies for sustainable biofuel production that do not use food crops or agricultural land.

"Biofuels are receiving increased attention as one strategy for addressing the dwindling supplies, high costs, and environmental consequences of fossil fuels," said Brookhaven biologist and lead author Daniel (Niels) van der Lelie, who leads the Lab's biofuels research program. "But competition with agricultural resources is an important socioeconomic concern."

Ethanol produced by fermenting corn, for example, diverts an important food source and the land it's grown on for fuel production. A better approach would be to use non-food plants, ideally ones grown on non-agricultural land, for biofuel production.

Van der Lelie's team has experience with plants growing on extremely marginal soil soil contaminated with heavy metals and other industrial chemicals. In prior research, his group has incorporated the molecular "machinery" used by bacteria that degrade such contaminants into microbes that normally colonize poplar trees, and used the trees to clean up the soil. An added benefit, the scientists observed, was that the microbe-supplemented trees grew faster even when no contaminants were present.

"This work led to our current search for bacteria and the metabolic pathways within them that increase biomass and carbon sequestration in poplar trees growing on marginal soils, with the goal of further improving poplar for biofuel production on non-agricultural lands," said co-author Safiyh Taghavi. In the current study, the scientists isolated bacteria normally resident in poplar and willow roots, which are known as endophytic bacteria, and tested selected strains' abilities to increase poplar growth in a controlled greenhouse environment. They also sequenced the genes from four selected bacterial species and screened them for the production of plant-growth promoting enzymes, hormones, and other metabolic factors that might help explain how the bacteria improve plant growth.

"Understanding such microbial-plant interactions may yield ways to further increase biomass," van der Lelie said.

The plants were first washed and surface-sterilized to eliminate the presence of soil bacteria so the scientists could study only the bacteria that lived within the plant tissues true endophytic bacteria. The plant material was then ground up so the bacterial species could be isolated. Individual strains were then supplemented with a gene for a protein that "glows" under ultraviolet light, and inoculated into the roots of fresh poplar cuttings that had been developing new roots in water. The presence of the endophytic bacteria was confirmed by searching for the glowing protein. Some bacterial species were also tested for their ability to increase the production of roots in the poplar cuttings by being introduced during the rooting process rather than afterward.

The results

The scientists identified 78 bacterial endophytes from poplar and willow. Some species had beneficial effects on plant growth, others had no effect, and some resulted in decreased growth. In particular, poplar cuttings inoculated with Enterobacter sp. 638 and Burkholderia cepacia BU72 repeatedly showed the highest increase in biomass production up to 50 percent as compared with non-inoculated control plants. Though no other endophyte species showed such dramatic effects, some were effective in promoting growth in particular cultivars of poplar.

In the studies specifically looking at root formation, non-inoculated plants formed roots very slowly. In contrast, plant cuttings that were allowed to root in the presence of selected endophytes grew roots and shoots more quickly.

The analysis of genes and metabolically important gene products from endophytes resulted in the identification of many possible mechanisms that could help these microbes thrive within a plant environment, and potentially affect the growth and development of their plant host. These include the production of plant-growth-promoting hormones by the endophytic bacteria that stimulate the growth of poplar on marginal soils.

The scientists plan to conduct additional studies to further elucidate these mechanisms. "These mechanisms are of prime importance for the use of plants as feedstocks for biofuels and for carbon sequestration through biomass production," van der Lelie said.


'/>"/>

Contact: Karen McNulty Walsh
kmcnulty@bnl.gov
631-344-8350
DOE/Brookhaven National Laboratory
Source:Eurekalert

Related biology news :

1. Scientists use lasers to measure changes to tropical forests
2. Scientists unlock possible aging secret in genetically altered fruit fly
3. Jefferson scientists discover a key protein regulator of inflammation and cell death
4. MUHC and McGill scientists explain genetic disease first discovered in Quebec 24 years ago
5. Scientists uncover evolutionary keys to common birth disorders
6. Invasive plants challenge scientists in face of environmental change
7. Key to future medical breakthroughs is systems biology, say leading European scientists
8. Scripps scientists develop first examples of RNA that replicates itself indefinitely
9. Florida professor creates endowment for insect scientists
10. NYU scientists discover dangerous new method for bacterial toxin transfer
11. Scientists can now differentiate between healthy cells and cancer cells
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/2/2017)... NEW YORK , March 2, 2017 Summary ... to better understand Perrigo and its partnering interests and activities ... ... The Partnering Deals and Alliance since 2010 report provides an ... world,s leading life sciences companies. On demand company ...
(Date:3/1/2017)... 2017  Aware, Inc. (NASDAQ: AWRE), a leading supplier ... P. Moberg has resigned, effective March 3, 2017, ... Officer and Treasurer of Aware citing a desire to ... member of the Board of Directors of Aware. ... Officer and co-President, General Counsel has been named Chief ...
(Date:2/27/2017)... , Feb. 27, 2017   Strategic Cyber Ventures ... it has led a $3.5 million investment in  Polarity ... Strategic Cyber Ventures is DC based and is led ... Hank Thomas . Ron Gula , also a ... also participated in this series A round of funding. ...
Breaking Biology News(10 mins):
(Date:3/23/2017)... , March 23, 2017  Agriculture technology company ... A financing and note conversion to commercialize its Cool ... is focused on developing products that are simultaneously profitable ... million in the last 18 months. This latest round ... Bridge Venture Partners. The company,s primary ...
(Date:3/22/2017)... , March 22, 2017  Ascendis Pharma A/S ... innovative TransCon technology to address significant unmet medical ... for the full year ended December 31, 2016. ... for our company as we broadened our pipeline ... integrated rare disease company with an initial focus ...
(Date:3/22/2017)... New York , March 22, 2017 ... is largely fragmented, states a research report by Transparency ... S.A., Pfizer Inc., Amgen Inc., and AbbVie Inc., accounted ... in 2015. The prominent players in this market are ... expand their product portfolio, which is likely to lead ...
(Date:3/22/2017)... ... 21, 2017 , ... Premier executive recruitment firm, Slone Partners, is proud to ... Scanlon Media. , Hunt Scanlon Media is one of the most respected ... source in the human capital sector. , “It is a great honor for Slone ...
Breaking Biology Technology: