Ecologists have long tried to understand global patterns of biological diversity by researching birds, butterflies, reptiles or plants, which are easily visible on the earth's surface and can be easily counted and analyzed. However, the study of the organisms present in the soil is complex and limited due to their microscopic size and because they are hidden in the earth.
Researchers from 24 countries led by Leho Tedersoo, from the University of Tartu (Estonia), have carried out an unprecedented study on soil organisms, specifically fungi. After examining 365 soil samples from around the world with a DNA sequencing method, called pyrosequencing, they have achieved numerous data unknown to date. The work, published today in the journal Science, has described more than 80,000 new species of fungi.
As the authors explain, the kingdom of fungi is one of the most diverse groups of organisms on Earth, and governs processes such as the soil carbon cycle, plant nutrition or pathologies. "Fungi are widely distributed in all terrestrial ecosystems, but the distribution of species, phyla and functional groups have been poorly documented to date," they point out.
Luis Villarreal Ruiz, from the Laboratory of Microbial Genetic Resources & Biotechnology (LARGEMBIO) in Mexico, who is actively participating in the study, recalls that despite the relevant role of fungi in the world's ecosystems and in human societies, “little was known on the general patterns of their diversity, distribution and function in terrestrial biomes ”, information on global diversity that was“ fragmented and imprecise ”.
In order to delve into the diversity and distribution of soil fungi in the world and the biotic (related to living organisms) and abiotic (those that are not the product of living organisms) factors that determine them, the researchers have analyzed 365 soil samples from global ecosystems using state-of-the-art massive genomic sequencing methods.
“The methodological design developed was innovative for world microbiology, by using combined methods of molecular ecology, metagenomics, bioinformatics, multivariate geostatistical analysis or global biogeographic analysis, among others. Next-generation massive genomic sequencing was used, the 454 pyrosequencing method. The 454 method is based on the chemistry of fireflies and with it the genome of the famous British scientist James Watson, co-discoverer of the DNA structure, was sequenced ”, adds Villareal Ruiz.
As the researcher details, since the formal studies on fungi began 285 years ago, around 100,000 species have been documented worldwide. Through this massive genetic study that began just over four years ago, an equivalent number of new species of fungi, 80,486, have been reported for the first time, exclusively inhabiting terrestrial ecosystems.
Likewise, the role of climate, soil, vegetation and spatial variables that govern the diversity patterns of soil fungi on a global scale has been unraveled. They have also shown for the first time that the distribution of the fungi that inhabit the planet is governed by their limitations in dispersal and climate and not by the vegetation where they inhabit, as previously thought.
“Given that the climatic variables explained in a greater proportion the richness and composition of the fungal communities, it is possible to know the impact that climate change may have on the spread of diseases; the consequences of altering native communities of soil microorganisms on ecosystem function; the mechanisms of dispersal of non-native microorganisms in other ecosystems that affect the native microbial biota and the economy and human health; how man can disperse harmful microorganisms; and the possibility of locating regions with a great wealth of microbial genetic resources useful for curing diseases, producing better food and protecting the environment ”, Villareal Ruiz summarizes.
Consortium for macroecology in fungi
Scientists from 36 universities and R & D & I centers from 24 countries on five continents have collaborated in the research that form the Fungal Macroecology Consortium, a global fungal research network made up of 58 microbiologists from Estonia, Benin, Sri Lanka, Mexico, Vietnam, USA, Zimbabwe, Italy, Germany, Australia, Thailand, Argentina, Cameroon, Sweden, Holland, Malaysia, Puerto Rico, Norway, Japan, China, New Zealand, Belgium and the United Kingdom .
The Consortium was created in 2011 to develop the current Global Microbial Metagenomics Project, funded by the European Union, the Estonian Science Foundation and the contributions of the 36 participating institutions. The first pilot sampling of the project was carried out in 2010 in the jungle region of the El Edén reserve, in Quintana Roo (Mexico). In the opinion of Luis Villareal Ruiz, this alliance "constitutes a massive effort and teamwork of synergy unprecedented in the history of world microbiology."