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
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.
This study was funded by the Office of Biological and Environmental Research within DOE’s Office of Science, by Brookhaven’s Laboratory Directed Research and Development Fund, and by the Flanders Science Foundation and the Institute for the Promotion of Innovation by Science and Technology in Flanders, both in Belgium.
Karen McNulty Walsh | EurekAlert!
Further reports about: > Biomass > Burkholderia cepacia BU72 > Enterobacter sp. 638 > Plant Growth > agricultural land > agricultural resources > bacteria > bacterial species > biofuel production > endophytic bacteria > environmental risk > food crop > mass production > metabolic pathways > plant-associated microbes > poplar trees
Algorithm could streamline harvesting of hand-picked crops
13.03.2018 | University of Illinois College of Engineering
A global conflict: agricultural production vs. biodiversity
06.03.2018 | Georg-August-Universität Göttingen
Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...
On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...
The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...
At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.
When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...
At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.
Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...
16.03.2018 | Event News
13.03.2018 | Event News
08.03.2018 | Event News
16.03.2018 | Earth Sciences
16.03.2018 | Physics and Astronomy
16.03.2018 | Life Sciences