Archaea endowed with plant growth promoting attributes

Abstract

The archaea are ubiquitous in extreme habitat and have been firstly reported from only in harsh environments, such as hot springs and salt lakes, but due to metagenomic, it revealed that archaea found in a broad range of habitats, including soils, oceans, and marshlands. Archaea are a major part of Earth’s planets and may play roles in C-cycle and N-cycle. The archaea belonged to mainly two phyla Euryarchaeota and Crenarchaeota, other groups have been tentatively created such as Nanoarchaeota and Korarchaeota, which contains a small group of unusual thermophilic species that shares features of both of the main phyla of Euryarchaeota and Crenarchaeota. Microorganisms, particularly eubacteria and fungi are known to play an important role in biogeochemical cycling and making available important nutrients like N, P, K, Fe and Zn to the plants through fixation, solubilization or mobilization of nu-trients. However, the role of archaea, that inhabits extreme environments, comprises more than 20% of the world’ biomass has not been well studied. There are few reports on plant growth promoting archaea including phosphorus solubilization, nitrogen fixation, siderophore production and Indole acetic acids production. Plant growth promoting attributes found in different archaea including Natrialba, Natrinema, Halolamina, Halosarcina, Halostagnicola, Haloarcula, Natronoarchaeum, Halobacterium, Halococcus, Haloferax and Haloterrigena. Due to unique adaptation to drastically varying ecosystems, archaea have special interest of potential biotechno-logical application in agriculture, medicine and industry.