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Due to the ever-changing climate, plants face stressors that limit their growth. Therefore it is vital to find new ways to protect plants from biotic and abiotic stressors such as pathogen infection, drought, heavy metal poisoning, and salinity. With an increasing population, limiting the effects of stress on plant growth and development for agriculture is vital. One approach to this is focusing on beneficial plant-microbe interaction, such as plant growth-promoting rhizobacteria (PGPR). These bacteria are found in the rhizosphere- the soil that is attached to the roots of a plant. Various PGPRs share a symbiotic relationship with plants and help plants cope with stresses. The purpose of this study is to isolate rhizospheric bacteria off Ceanothus velutinus (snowbrush), a plant native to the Intermountain West region of North America. This plant thrives in dry and harsh conditions. The rhizosphere soil of the snowbrush plant was collected from the Tony Grove Region of Logan, Utah. Samples were diluted and cultured using the spread plate method. Unique colonies were isolated and purified by streak plate technique. The isolated colonies were tested for Gram staining, catalase activity, and morphological characteristics. Ten randomly selected bacterial species were sequenced for 16s rRNA and identified by BLAST against the 16s rRNA database at NCBI. Many of the isolated colonies belonged to the genus Streptomyces, which aids in nutrient absorption, antibiotic production, and antioxidant activity. Other identified bacterial species included Terrabacter spp., aiding in nutrient mineralization. We are working on isolating more bacteria species from the rhizosphere of snowbrush, identifying and validating their functions.


Utah State University

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Physical Sciences and Mathematics

Isolation and Purification of Bacterial Species from Rhizosphere of Native Plant Ceanothus velutinus (Snowbrush)