Plant growth-promoting endophytic bacteria associated with Halocnemum strobilaceum (Pall.) M.Bieb and their plant beneficial traits

Abstract

Halocnemum strobilaceum (Pall.) M.Bieb. is a halophyte desert plant. The plant is known for its antioxidant, antimicrobial, insecticidal and phytoremediation properties. Halocnemum strobilaceum grows in severe salinity and drought conditions and its’ survival can be associated with activity of endophytic bacteria. The aim of the research was to reveal and study plant growth-promoting endophytic bacteria isolated from Halocnemum strobilaceum (Pall.) M.Bieb. The plants were collected from Kyzylkum desert in Uzbekistan. The endophytic bacteria were isolated from Halocnemum strobilaceum (Pall.) M.Bieb. tissues and screened for cotton (Gossypium hirsutum L.) growth-promoting activity. As a result the most active isolates HAST-2, HAST-7, HAST-9, HAST-10 and HAST-17 were selected. The cotton seeds’ inoculation with these bacterial isolates resulted in significant improvement of seeds germination, root and shoot length, and fresh plant weight due to their ability to fix nitrogen, produce indole-3-acetic acid (IAA), 1-aminocyclopropane-1-carboxylate (ACC) deaminase, siderophores and solubilize phosphates. The chosen isolates were identified using 16S rRNA gene analysis and registered in GenBank (NCBI) as Bacillus megaterium HAST-2, Bacillus aryabhattai HAST-7, Pseudomonas plecoglossicida HAST-9, Pseudomonas putida HAST-10 and Pseudomonas chlororaphis HAST-17. These strains can be used as bio-inoculants to improve the growth of cotton and other crops.

A Plant Endophytic Bacterium Priestia megaterium StrainBP-R2 Isolated from the Halophyte Bolboschoenus planiculmis Enhances Plant Growth under Salt and Drought Stresses

“…When plants grow in severe salinity and drought environments, the presence of endophytic bacteria in these plants may help them to survive and grow in these conditions. Several studies have shown the beneficial effects of endophytic bacteria on their host plants, such as the Salicornia brachiate [ 21 ] plant, Cicer arietinum [ 22 ], Haloxylon ammodendron [ 23 ], Nypa fruticans [ 24 ], Salicornia bigelovii [ 25 ], Armoracia rusticana [ 26 ], Seidlitzia rosmarinus [ 27 ], Calendula officinalis [ 28 ], Halocnemum strobilaceum [ 29 ], Haloxylon aphyllum [ 30 ], Tetragonia tetragonioides [ 31 ], and other plants. In this study, we have isolated an endophytic bacterium from the salt marsh halophyte, Bolboschoenus planiculmis .…”

Population of Halocnemum strobilaceum (Pall.)M.Bieb in a Dry Salt Lake of the Central Kyzylkum

“…Like almost all xerophytes and halophytes, sarsazan does not have developed leaves, is able to accumulate salts in its tissues, and tolerates extreme soil salinity. Therefore, H. strobilaceum is classified as a hyperhalophyte (14,15). Data from the IR spectrum analysis were used to study soil samples around the root system of H. strobilaceum, as well as soil around it at the site of the studied drying lake.…”

Mechanisms of Salt Stress Reduction in Plants Using Salt-Resistant Bacteria Isolated From Halophytes

“…Кроме того, эти корни являются источником галотолерантных N 2 -фиксирующих бактерий с потенциалом стимулирования роста растений [31], некоторые из которых усиливают рост галофитов, а также негалофитных культур на засоленных почвах. Потенциальные преимущества биологических фиксаторов азота для галофитов и чувствительных к засолению культур, подчеркивают интерес к изучению галотолерантных PGPR и эндофитных бактерий, фиксирующих N 2 , в качестве потенциальных источников биоудобрений для засоленных почв [32].…”