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Researchers have discovered that beneficial soil bacteria give plants an unexpected survival advantage in salty soils。 Instead of helping plants keep salt out, the microbes stimulate the production of lignin, a natural compound that strengthens roots and makes plants more resilient。 Greenhouse and field tests showed healthier plants and higher yiel
In nature, plants abundantly form beneficial associations with soilborne microbes that are important for plant survival and, as such, affect plant biodiversity and ecosystem functioning. Classical examples of symbiotic microbes are mycorrhizal fungi that aid in the uptake of water and minerals, and Rhizobium bacteria that fix atmospheric nitrogen for the plant. Several other types of beneficial soilborne microbes, such as plant-growth-promoting rhizobacteria and fungi with biological control activity, can stimulate plant growth by directly suppressing deleterious soilborne pathogens or by priming aboveground plant parts for enhanced defense against foliar pathogens or insect herbivores. The establishment of beneficial associations requires mutual recognition and substantial coordination of plant and microbial responses. A growing body of evidence suggests that beneficial microbes are initially recognized as potential invaders, after which an immune response is triggered, whereas, at later stages of the interaction, mutualists are able to short-circuit plant defense responses to enable successful colonization of host roots. Here, we review our current understanding of how symbiotic and nonsymbiotic beneficial soil microbes modulate the plant immune system and discuss the role of local and systemic defense responses in establishing the delicate balance between the two partners.
Microbes are the most abundant and diverse organisms on Earth. In contrast to macroscopic organisms, their environmental preferences and ecological interdependencies remain difficult to assess, requiring laborious molecular surveys at diverse sampling sites. Here, we present a global meta-analysis of previously sampled microbial lineages in the environment. We grouped publicly available 16S ribosomal RNA sequences into operational taxonomic units at various levels of resolution and systematically searched these for co-occurrence across environments. Naturally occurring microbes, indeed, exhibited numerous, significant interlineage associations. These ranged from relatively specific groupings encompassing only a few lineages, to larger assemblages of microbes with shared habitat preferences. Many of the coexisting lineages were phylogenetically closely related, but a significant number of distant associations were observed as well. The increased availability of completely sequenced genomes allowed us, for the first time, to search for genomic correlates of such ecological associations. Genomes from coexisting microbes tended to be more similar than expected by chance, both with respect to pathway content and genome size, and outliers from these trends are discussed. We hypothesize that groupings of lineages are often ancient, and that they may have significantly impacted on genome evolution.
A new study suggests Earth may have been sending tiny hitchhikers to Venus for billions of years。 Researchers found that asteroid impacts could launch microbes into space, where some might survive the journey and end up suspended in Venus' clouds。 If future missions detect life there, there's a surprising chance it didn't originate on Venus at all—
A centimeter-sized crystal has revealed clear signs of quantum entanglement, showing that large, everyday objects can display surprisingly deep quantum behavior。 The discovery could help solve the mystery of strange metals while opening new possibilities for ultra-precise quantum sensors and other advanced technologies
Physicists have developed a new optical centrifuge that can precisely spin molecules inside a superfluid for the first time。 The advance could help unravel some of the biggest mysteries of quantum liquids and reveal how superfluidity breaks down at the atomic scale
Researchers have achieved a major milestone by creating a long-sought two-dimensional quantum material and confirming its unusual conducting edge states。 The ability to control these states through strain could make the material a promising platform for future room-temperature quantum electronics
A strange "chirping" signal from a distant supernova has revealed the birth of a magnetar, confirming that these incredibly magnetic neutron stars can power the universe's brightest stellar explosions。 The discovery also marks the first time Einstein's general relativity has been used to explain the mechanics of a supernova
Ultra-fine bubbles may offer a cleaner way to perfect inkjet printing for next-generation electronics。 By simply changing the number of bubbles in each droplet, researchers were able to dramatically reshape the final printed pattern without leaving behind unwanted chemical residues
An unusual gravitational wave signal has renewed hopes that primordial black holes, long considered purely theoretical, may finally be within reach of discovery。 If confirmed, they could solve one of astronomy's greatest mysteries by explaining the nature of dark matter
Astronomers may have witnessed one of the rarest and most dramatic cosmic events ever seen: a long-sought intermediate-mass black hole ripping apart a dense white dwarf star and devouring it。 The Einstein Probe space telescope caught the explosion in its earliest moments, revealing an unusual sequence of intense X-ray flashes unlike anything seen i
Wildfires produce a charcoal layer, which has an adsorbing capacity resembling activated carbon. After the fire a new litter layer starts to accumulate on top of the charcoal layer, which liberates water‐soluble compounds that percolate through the charcoal and the unburned humus layer. We first hypothesized that since charcoal has the capacity to adsorb organic compounds it may form a new habitat for microbes, which decompose the adsorbed compounds. Secondly, we hypothesized that the charcoal may cause depletion of decomposable organic carbon in the underlying humus and thus reduce the microbial biomass. To test our hypotheses we prepared microcosms, where we placed non‐heated humus and on top one of the adsorbents: non‐adsorptive pumice (Pum), charcoal from Empetrum nigrum (EmpCh), charcoal from humus (HuCh) or activated carbon (ActC). We watered them with birch leaf litter extract. The adsorbing capacity increased in the order Pum<HuCh<EmpCh<ActC, the adsorbents being capable of removing 0%, 26%, 42% and 51% of the dissolved C org in the litter extract, respectively. After one month, all adsorbents harboured microbes, but their amount and basal respiration was largest in EmpCh and HuCh, and smallest in Pum. In addition, different kinds of microbial communities with respect to their phospholipid fatty acid and substrate utilization patterns were formed in the adsorbents. The amount of microbial biomass and number of bacteria did not differ between humus under different adsorbents, although different microbial communities developed in humus under EmpCh compared with Pum, which is obviously related to the increased pH of the humus under EmpCh, and also ActC. We suggest that charcoal from burning can support microbial communities, which are small in size but have a higher specific growth rate than those of the humus. Although the charcoal layer induces changes in the microbial community of the humus, it does not reduce the amount of humus microbes.
Scientists have combined machine learning with quantum physics to discover two new superconductors and create a much faster way to search for many more。 The technique could bring researchers significantly closer to the long-sought goal of a room-temperature superconductor
Researchers discovered that electricity can dramatically reshape how heat flows through certain ceramic materials, increasing heat conduction by almost threefold in a preferred direction。 The unexpected result could lead to much more efficient cooling technologies and energy-saving devices
What if time doesn't actually exist until something changes。 Scientists at the University of Birmingham created a tiny "mini universe" using 24,000 ultracold atoms and showed that the flow of time can emerge naturally from changes inside a quantum system, without relying on any external clock
A decades-old puzzle about water has finally been unraveled。 Researchers found that water trapped in tiny nanoscale spaces is not inherently more reactive。 Instead, the intense pressures created inside these microscopic gaps explain most of the effect, while the surrounding material can further enhance water's chemistry if it interacts with the rea