Cyanobacterial inoculation as resource conserving options for improving the soil nutrient availability and growth of...

Harnessing the benefits of plant-microbe interactions towards better nutrient mobilization and plant growth is an important challenge for agriculturists globally. In our investigation, the focus was towards analyzing the soil-plant-environment interactions of cyanobacteria-based formulations (Anabaena-Nostoc consortium, BF1-4 and Anabaena-Trichoderma biofilm, An-Tr) as inoculants for ten maize genotypes (V1-V10). Field experimentation using seeds treated with the formulations illustrated a significant increase of 1.3- to 3.8-fold in C-N mobilizing enzyme activities in plants, along with more than five- to six-fold higher values of nitrogen fixation in rhizosphere soil samples. An increase of 22-30% in soil available nitrogen was also observed at flag leaf stage, and 13-16% higher values were also recorded in terms of cob yield of V6 with An-Tr biofilm inoculation. Savings of 30 kg N ha^-1 season^-1 was indicative of the reduced environmental pollution, due to the use of microbial options. The use of cyanobacterial formulations also enhanced the economic, environmental and energy use efficiency. This was reflected as 37-41% reduced costs lowered GHG emission by 58-68 CO₂ equivalents and input energy requirement by 3651-4296 MJ, over the uninoculated control, on hectare basis. This investigation highlights the superior performance of these formulations, not only in terms of efficient C-N mobilization in maize, but also making maize cultivation a more profitable enterprise. Such interactions can be explored as resource-conserving options, for future evaluation across ecologies and locations, particularly in the global climate change scenario.