Molecular Profiling of Rhizosphere Bacterial Communities Associated with Prosopis juliflora and Parthenium hysterophorus

Abstract

Prosopis juliflora and Parthenium hysterophorus are the two arid, exotic weeds of India that are characterized by distinct, profuse growth even in nutritionally poor soils and environmentally stressed conditions. Owing to the exceptional growth nature of these two plants, they are believed to harbor some novel bacterial communities with wide adaptability in their rhizosphere. Hence, in the present study, the bacterial communities associated with the rhizosphere of Prosopis and Parthenium were characterized by clonal 16S rRNA gene sequence analysis. The culturable microbial counts in the rhizosphere of these two plants were higher than bulk soils, possibly influenced by the root exudates of these two plants. The phylogenetic analysis of V1_V2 domains of the 16S rRNA gene indicated a wider range of bacterial communities present in the rhizosphere of these two plants than in bulk soils and the predominant genera included Acidobacteria, Gammaproteobacteria, and Bacteriodetes in the rhizosphere of Prosopis, and Acidobacteria, Betaproteobacteria, and Nitrospirae in the Parthenium rhizosphere. The diversity of bacterial communities was more pronounced in the Parthenium rhizosphere than in the Prosopis rhizosphere. This culture-independent bacterial analysis offered extensive possibilities of unraveling novel microbes in the rhizospheres of Prosopis and Parthenium with genes for diverse functions, which could be exploited for nutrient transformation and stress tolerance in cultivated crops.

Microbial Ecology of Qatar, the Arabian Gulf: Possible Roles of Microorganisms

“…Moreover, in many clinical situations (Mignard and Flandrois, 2006), these methods are time-consuming and fail to identify some bacteria groups (for example, Gram-positive rods). Other studies have found the rhizosphere of P. juliflora harbors more diversified bacteria communities from various phyla than the non-rhizosphere areas, which means that such bacteria communities might boost the nutritional status for crops and wild plants (Jothibasu et al, 2012). In this study, the molecular approach to investigate the bacterial activity at the rhizosphere of P. juliflora revealed that the culturable microbes were higher than those remote of the rhizosphere region, and the root exudates of this plant might influence such activity.…”

“…These substances might play active roles related to the availability of nutrients and phytoremediation of various compounds (organic and inorganic origin). It has been reported that the rhizospheres of some arid plants (e.g., Prosopis juliflora) offer niches for bacteria that exert beneficial effects, including nutrient transformation, plant growth promotion, disease suppression, resistance to drought and salinity, and might remediate pollutants of various origin (Jothibasu et al, 2012;Yasseen and Al-Thani, 2013;Yasseen, 2014a). Al-Thani (2007) showed that soil populations of bacteria at the rhizosphere were quite different from the non-rhizosphere sites.…”

Silvopastoral systems in dry Chaco, Argentina: Impact on soil chemical parameters and bacterial communities

“…These taxonomic classes have many important biological roles, especially in the carbon and nitrogen cycles, including metabolic strategies such as nitrogen fixation, ammonia oxidation and methylotrophy (Dube et al, 2019;Kotzé et al, 2017;Vasileiadis et al, 2015). Previously, Jothibasu et al (2012) observed a dominant presence of Acidobacteria, followed by Alphaproteobacteria and Bacteroidetes in the Prosopis rhizosphere. Interestingly, no Firmicutes were reported in any of their clonal libraries.…”

Invasive Plant Alternanthera philoxeroides Benefits More Competition Advantage from Rhizosphere Bacteria Regardless of the Host Source

“…For example, Bromus tectorum can alter and disturb the composition and structure of rhizosphere mycorrhizal communities [20][21][22]. The invasive species Prosopis juliflora can alter its root bacterial and fungal community diversity, thereby enhancing its root colonization and increasing dry biomass and plant phosphorus, and supporting its growth and invasion [23,24]. Alnus trabeculosa increases soil bacterial diversity in invaded areas [25].…”