Evaluation of synergistic effects of bacterial and cyanobacterial strains as biofertilizers for wheat

Abstract

An investigation was undertaken to screen, select and evaluate a set of bacterial and cyanobacterial isolates from the wheat rhizosphere for their role as biofertilizers in wheat. From an initial set of 23 cyanobacterial strains and 110 bacterial isolates from wheat rhizospheric soil, 3 bacterial and 3 cyanobacterial strains were selected based on their plant growth promoting potential under laboratory and controlled greenhouse conditions. In vitro compatibility studies revealed positive interactions among the six strains. Pot experiments were conducted with wheat variety HD 2687, with a total of 51 treatments, along with recommended fertilizer controls. Various combinations of the selected set of three bacterial (PW1, PW5 and PW7) and three cyanobacterial isolates (CW1, CW2 and CW3) were used along with 1/3 N and full dose of P and K fertilizers. Significant enhancement in the soil microbiological (Dehydrogenase activity, FDA hydrolase, Alkaline phosphatase and microbial biomass) and plant growth/yield parameters were recorded. Observations revealed a two-fold increase in panicle weight in selected combinations (PW1+PW7+CW3; PW1+ CW1+CW2/CW1+CW3; CW2+CW3), as compared to control treatment involving full dose of chemical fertilizers. Such combinations, which also provided N savings of 40-80 kg N/ha are being further evaluated in field experiments. This study for the first time illustrated the positive and dynamic interactions among bacterial and cyanobacterial strains and their promise in integrated nutrient management of wheat crop.

Effectiveness of cyanobacteria and green algae in enhancing the photosynthetic performance and growth of willow (Salix viminalis L.) plants under limited synthetic fertilizers application

“…Our results are in line with the studies of other researchers (Falch et al 1995, Kreitow et al 1999, Burja et al 2001, Nain et al 2010, and Rana et al 2012 who demonstrated the stimulatory influence of green-blue algae on wheat development and their inhibitory effect on pathogenic microflora growth, by synthesizing some active compounds, which inhibit the growth of bacteria and fungi. The presented results also agree with reports of Rastogi and Singha (2009) who indicated that some cyanobacterial secondary metabolites were toxic to living organisms.…”

Developments in Cyanobacterial Biofertilizer

“…VAM, PS and cyanobacteria. A similar pattern of observations has been reported by many workers based on the interaction studies between nitrogen fixing microorganisms [5,11,33,40,41]. These benefits may also be due to the combined influence of nutrient supply as well as bioprotection [38].…”

Enhancing micronutrient uptake and yield of wheat through bacterial PGPR consortia

“…PGPR are known to employ one or more direct and indirect mechanisms of action to improve plant growth and health, although the major mode of action of many PGPR is through increasing the availability of nutrients for the plant in the rhizosphere region (Glick 1995). PGPR play an important role not only in cereal crops (Karthikeyan et al 2007;Selvakumar et al 2008;Prasanna et al 2009;Manjunath et al 2010;Nain et al 2010) but also for production of horticultural (Baset et al 2010) and other crops (Khalid et al 2004;Fischer et al 2007;Gholami et al 2009). However, the enhancement of crop growth has been mainly evaluated in terms of crop yields.…”