Physiological characterization and electron microscopic investigation of cyanobacteria associated with wheat rhizosphere

• Published in: Folia microbiologica Vol. 54; no. 1; pp. 43 - 51
• Main Authors: Karthikeyan, N.,Indian Agricultural Research Inst., New Delhi (India). Div. of Microbiology, Prasanna, R.,Indian Agricultural Research Inst., New Delhi (India). Div. of Microbiology, Sood, A.,Indian Agricultural Research Inst., New Delhi (India). Div. of Microbiology, Jaiswal, P.,Indian Agricultural Research Inst., New Delhi (India). Div. of Microbiology, Nayak, S.,Indian Agricultural Research Inst., New Delhi (India). Div. of Microbiology, Kaushik, B.D.,Indian Agricultural Research Inst., New Delhi (India). Div. of Microbiology
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.01.2009
• Subjects: AIA; Applied Microbiology; Biomedical and Life Sciences; BLE; CALOTHRIX; CYANOBACTERIA; Cyanobacteria - isolation & purification; Cyanobacteria - physiology; Cyanobacteria - radiation effects; Cyanobacteria - ultrastructure; Environmental Engineering/Biotechnology; GERMINACION; GERMINATION; http://www.fao.org/aos/agrovoc#c_15960; http://www.fao.org/aos/agrovoc#c_16266; http://www.fao.org/aos/agrovoc#c_3247; http://www.fao.org/aos/agrovoc#c_3778; http://www.fao.org/aos/agrovoc#c_37796; http://www.fao.org/aos/agrovoc#c_37827; http://www.fao.org/aos/agrovoc#c_4810; http://www.fao.org/aos/agrovoc#c_6569; http://www.fao.org/aos/agrovoc#c_6651; http://www.fao.org/aos/agrovoc#c_7951; http://www.fao.org/aos/agrovoc#c_8373; IAA; Immunology; Indoleacetic Acids - metabolism; Life Sciences; Microbiology; MICROSCOPIA; MICROSCOPIE; MICROSCOPY; Microscopy, Electron; NOSTOC; Plant Roots - growth & development; Plant Roots - microbiology; RACINE; RAICES; RHIZOSPHERE; RIZOSFERA; ROOTS; Soil Microbiology; TRIGO; Triticum - growth & development; Triticum - microbiology; TRITICUM AESTIVUM; WESTIELLOPSIS; WHEATS; Wheat Seedling; Wheat Rhizosphere; Coleoptile Length; Cyanobacterial Isolate; Cyanobacterial Strain
• ISSN: 0015-5632; 1874-9356
• DOI: 10.1007/s12223-009-0007-8

Physiological attributes of a set of cyanobacterial strains, isolated from the rhizosphere of wheat (var. HD 2687), identified as belonging to the genera Calothrix (n=3), Westiellopsis (1), Hapalosiphon (2) and Nostoc (2), were axenized and evaluated. The concentrated culture filtrates of three cyanobacterial strains, C. ghosei, H. intricatus and Nostoc sp., were able to enhance germination percentage, radicle and coleoptile length in inhibition experiments with wheat seeds. Indole-3-acetic acid (IAA) production was recorded in light and dark (+0.5 % glucose) incubated cultures. Incubation in the presence of tryptophan significantly enhanced IAA production. Acetylene-reducing activity was higher in light incubated cultures of Nostoc sp. followed by C. ghosei, while in the dark, C. ghosei recorded the highest values. TLC of the filtrates revealed the presence of several amino acids such as histidine and auxin-like compounds. Co-culturing with selected strains recorded significant enhancement in plant chlorophyll levels. Root sections of wheat seedlings co-cultured with C. ghosei revealed the presence of short filaments inside the root hairs and cortical region. Such strains can be promising candidates for developing plant growth promoting associations for wheat crop, besides serving as model systems for understanding the metabolic interactions of cyanobacteria with host plant, such as wheat.