Indoleacetic acid production and chromium reduction by cyanobacteria Synechocystis SP. P2A (Chroococcales) immobilized in alginate beads

Abstract

A simple extrusion method was used to entrap Synechocystis sp.P2A in alginate beads. The viability, growth response and Indoleacetic acid (IAA) production at different pH were studied in alginate immobilized Synechocystis sp.P2A. 2.6% sodium alginate (w/v) and pH-7 was found to be optimum for growth of Synechocystis sp. P2A as well as IAA production (79µg/ml). To prepare effective formulation for plant inoculation, alginate beads were further modified by coating with chitosan or chitosan-polyethylene glycol. Effect of all formulations containing Synechocystis sp. P2A in free and immobilized form on growth of Triticumaestivum was evaluated. Soil inoculation of entrapped Synechocystis in alginate beads coated with chitosan resulted in 20% increase in root length and 14% increase in dry weight as compared to non-inoculated seedlings. Free and immobilized cyanobacteria were allowed to grow in BG11 medium supplemented with 100µg/ml K 2 CrO 4 and chromium reduction was measured at variable pH. At pH 7 immobilized showed 5% more reduction than free form. The current study showed that alginate immobilized Synechocystis sp. P2A can accomplish viable functions including plant growth promoting hormone production and chromium reduction and therefore propose an efficient and convenient method for storage and use of cyanobacteria.

Groundnut grain yield responses to inoculation with Bradyrhizobium sp. and cyanobacteria

“…In addition, the cyanobacteria IPR7059 and IPR7061 were chosen to be co-inoculated with Bradyrhizobium sp. SEMIA6144 because their genera have been related to plant growth in other crops (Bhowmik et al 2010;Khurshid et al 2017;Sivalingam 2020;Supraja et al 2020a). Despite initial evidences of plant growth stimulation in other crops, there were only signi cant effects on nodule mass in Umuarama due to co-inoculation of strain SEMIA6144 with Arthrospira platensis IPR 7059 (Table 3), and higher (but not signi cant) grain yield in Paranavaí due to co-inoculation with IPR7061 (Table 2).…”

“…The second one, Synechocystis sp. is also a unicellular non-nitrogen xing cyanobacterium that primarily inhabits water environments and soil, which has been characterized for the elevated production of phytohormones when inoculated in the rhizosphere of wheat (Triticum aestivum) (Khurshid et al 2017).…”

Does coinoculation with bradyrhizobia and cyanobacteria improve groundnut growth and yield?

“…In our study, the cyanobacteria IPR7059 and IPR7061 were chosen to be coinoculated with B. arachidis (SEMIA6144) because these genera are related to plant growth in other crops (Bhowmik et al., 2010; Khurshid et al., 2017; Sivalingam, 2020; Supraja et al., 2020). According to Liebig’s law of the minimum, crop yield is limited by the lack of one or more factors that are present in lesser quantities.…”

“…The first, Arthrospira ( Spirulina ) platensi s, is a filamentous cyanobacterium that grows under photoautotrophic conditions and does not fix N. When inoculated in Phaseolus aureus or P. mungo seeds (Bhowmik et al., 2010) or applied as a biofertilizer in Begonia semperflorens (Jowkar et al., 2017), rice (Dineshkumar et al., 2018), tomato (Supraja et al., 2020), or groundnut (Sivalingam, 2020), it increases seed germination and plant growth. The second species, Synechocystis sp., is also a unicellular nonnitrogen-fixing cyanobacterium that primarily inhabits water environments and soil and has been characterized by elevated production of phytohormones when inoculated in the rhizosphere of wheat (Khurshid et al., 2017).…”