Now research led by Michigan Technological University scientists has identified the molecular mechanism that Populus—the scientific name for common poplars, cottonwoods and aspens—uses to adapt to changing soil conditions, as well as some of the genes that turn the process off or on. They hope to apply what they’ve learned to find ways to use biotechnology or selective breeding to modify the trees to make them more stress-tolerant.
“Our hope is that by understanding how this works, we can manipulate the system so the plants can adapt faster and better to stressful conditions,” explained Victor Busov, associate professor in Michigan Tech’s School of Forest Resources and Environmental Science and senior author on a paper published in the March 2010 issue of the journal The Plant Cell.
Busov and colleagues at Michigan Tech, the University of Georgia, Oregon State University and the Beijing Forestry University in China analyzed thousands of genes in the Populus genome, the only tree genome that has been completely sequenced. They were searching for the mechanism that regulates the plant’s decision to grow tall or to spread its roots out in an extensive underground exploration system that can sample the soil near and far until it finds what the rest of the plant needs.
The key players turned out to be a family of hormones called gibberellins, referred to by the scientists as GAs.
“GAs’ role in root development is poorly understood,” said Busov, “and the role of GAs in lateral root formation is almost completely unknown.” Lateral roots are the tangle of tiny roots that branch out from the primary root of a plant. ”They are the sponges,” Busov explained, “the ones that go looking for nutrients, for water—the ones that do most of the work.”
The researchers found that GAs interact with other plant hormones such as auxin to tell the plant whether to concentrate on reaching for the sky or on building a bigger, better network of roots under ground. “The GAs and auxin are definitely talking, molecularly,” said Busov.
Growing poplar seedlings mutated to make them GA-deficient, the scientists compared their root and stem growth to others that contained moderate amounts of GAs and a control group of wild-type plants with normal GAs. They found that more GAs, the more a plant’s stem flourished, but its roots remained spindly. When GA production was shut down, either by using mutants that lacked the necessary genes or by silencing the genes that form the molecular on-off switch, the resulting plants looked dwarfed, but their lateral roots grew luxuriant and full.
Application of GA to the GA-deficient dwarf plants rapidly reversed the process. The plants grew tall, but their lateral root systems shriveled.
“Clearly, lack of the hormone promotes growth below ground, while the hormone itself promotes growth above ground,” said Busov. “This is a natural mechanism that we don’t know much about. It’s always a tradeoff between growth above ground and growth below ground. Normally there is a fine balance, and this balance is a little disturbed under stress.”
In a commentary on the research published in the same issue of the journal, Kathleen Farquharson, science editor of The Plant Cell, wrote: “This study provides important insights into how plant hormones regulate lateral root development.”
The research was supported in part by grants from the US Department of Energy’s Poplar Genome Based Research for Carbon Sequestration in Terrestrial Ecosystems project ad by the US Department of Agriculture’s National Plant Genome initiative.
Michigan Technological University (mtu.edu) is a leading public research university developing new technologies and preparing students to create the future for a prosperous and sustainable world. Michigan Tech offers more than 130 undergraduate and graduate degree programs in engineering; forest resources; computing; technology; business; economics; natural, physical and environmental sciences; arts; humanities; and social sciences.
Jennifer Donovan | Newswise Science News
Six-legged livestock -- sustainable food production
11.05.2017 | Faculty of Science - University of Copenhagen
Elephant Herpes: Super-Shedders Endanger Young Animals
04.05.2017 | Universität Zürich
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy