Plants often develop communities with microorganisms in their roots, which influences plant health and development. Although the recruitment of these microbes is dictated by several factors, it is unclear whether the genetic variation in the host plants plays a role. In a new study, researchers from the University of Illinois Urbana-Champaign explored this question and their work can help improve agriculture productivity.
“Previously, researchers have only looked at what kind of microbes are present in association with plants, but not what might be driving the formation of these communities and how we might be able to control these drivers through plant breeding,” said Angela Kent (CABBI), a professor of natural resources and environmental sciences.
Microbes form complex communities called microbiomes in and around the roots of plants. The host plants can dictate which microbes are invited into their roots—known as endophytes—using chemical signals. They can also alter the soil properties around the roots to influence which microbes can grow around the root surface, or rhizosphere. However, in order to breed plants based on what microbes they associate with, researchers first need to understand the extent to which plant genomes can influence the rhizosphere microbiome.
To answer this question, the researchers studied two native silver grass species—Miscanthus sinensis and Miscanthus floridulus. These plants are considered potential bioenergy crops because they require lower nutrient concentrations to achieve more growth compared to traditional crops.
The study was conducted in 16 sites across Taiwan and included a range of environmental conditions, such as hot springs, mountain peaks, and valleys, to represent all possible environmental extremes. The researchers collected 236 rhizosphere soil samples from randomly selected Miscanthus plants and also isolated the microbiome inside the roots.
“Although the scale of this study was unprecedented, we were mindful of the plant protection and quarantine regulations. We processed the samples in Taiwan to extract the endophytic microbial community and collect the rhizosphere microbiome,” Kent said.
The researchers used two types of DNA sequencing techniques in their study. The microbiomes in and around the roots were identified using the DNA sequence of bacterial and fungal rRNA genes, focusing on the part of the genome that is unique to each species. The variation in the plant genome was measured using microsatellites, which are small pieces of repeating DNA that can distinguish even closely related plant populations.
Source: eurekalert.org
Photo Credit: istockgetty-images-plus-claraveritas
Categories: Illinois, Crops