Ever-present but undetectable to the naked eye, micro-predators like viruses, nematodes, protists, and some bacteria are constantly working in the soil to hunt and kill the pathogens that threaten plants. But how they do this "dirty" work is not well understood.
The USDA National Institute of Food and Agriculture (NIFA) has awarded $3.5 million to a UF/IFAS scientist and his team to study these powerful organisms and share research findings to promote crop productivity and sustainable soil health management.
Samuel Martins, a UF/IFAS assistant professor of plant pathology, is leading eight researchers from six institutions: the University of Florida; Pennsylvania State University; the Connecticut Agricultural Experiment Station; the University of California, Davis; William Paterson University in Wayne, New Jersey; and the USDA Agricultural Research Service.
The team will collect soil before and after harvest at 12 organic tomato farms in California, Connecticut, Florida, and Pennsylvania. After extracting DNA from samples, they will conduct computational analyses to identify the soil's microbial and viral composition and determine associations between predators and prey.
The researchers propose to test the effects of various organic amendments like worm casings and chicken manure on micro-predators and pathogens. They want to learn whether micro-predator predation can be enhanced in the soil with amendments to better protect plants.
"Our long-term goal is to investigate the impact of different organic matter amendments on micro-predator diversity, pathogen survival, and soil and plant health," Martins said.
Samuel Martins
The researchers will eventually share their findings with growers through webinars and conferences and with university students through new curricula.
They selected the research project based on grower needs; planning grant-funded trips to grower association workshops around the country, as well as surveys they conducted to learn which functions of soil are important to growers. The results, based on the responses of 99 growers, indicate that 89% consider building organic matter important, and 82% consider pathogen suppression important.
The growers "appreciated the cutting-edge data and refreshing honesty about the state of knowledge of soil microbiomes (despite decades of sequence surveys, we still cannot confidently tell a grower how to use soil microbiome data to inform management decisions)," the researchers wrote in their proposal.
Members of a panel that evaluated the team's NIFA proposal praised Martins' team for engaging stakeholders to develop their research project. They also confirmed statements made within the proposal indicating a lack of similar research in the United States.
"The panel was enthusiastic about this proposal and agreed that the team's proposed research ideas are novel and will significantly add to the scientific community's knowledge base on micro-predators in soil and their impact on disease suppression in soils," according to a summary of the panel's findings.
Source: UF/IFAS.