ABSTRACT
The characteristics of two cyanobacterial strains, Anabaena oryzae and Nostoc muscorum, were studied in order to use them as biofertilizers in a field experiment conducted in the two winter seasons of 2021 and 2022 at the Ismailia Agricultural Research Center Station to study the effect of both strains on peanut plant in sandy soil. Cyanobacterial strains were used individually by coating seed, soil drench, and foliar applications, as well as mixed applications of two strains in various ways. Both cyanobacterial strains morphological examination revealed that they both have heterocysts, nitrogen, phosphorus, and potassium in their culture filtrate, and they were able to produce chlorophyll a and phosphatase enzymes. The results of an agricultural experiment showed that using Nostoc muscorum and Anabaena oryzae separately had a positive effect on peanut plants in a variety of applications, but combining both of these applications with 75% nitrogen increased the growth traits, nutrient contents, and soil biological activities in both peanut plants and their rhizosphere soil. The soil drench treatment with A. oryzae and Nostoc muscorum plus 75% nitrogen produced the highest growth results and peanut yields in a single application. The A. oryzae Soil Drench Application (S) + N. muscorum Foliar Application (F) with 75% N reported the best outcomes in mixed treatments. However, compared to single applications, all blended applications displayed better growth and yield characteristics. The results of the study suggest that employing cyanobacteria in a mixed application will enhance its advantages over a single use.
ABSTRACT
Aims: To investigate the effect of NaCl stress on parent Nostoc muscorum and its spontaneously occurring mutant clone showing resistance to growth inhibitory action of NaCl in terms of various physiological parameters. We have further analyzed the role of iron uptake systems in providing a resistant phenotype. Place and Duration of Study: Division of Microbiology, Department of Botany, Government Motilal Science College, Bhopal 462008 (M.P.) India. This work was carried out between August 2021 to May 2022. Methodology: We have examined the various physiological parameters viz. growth, specific growth rate, photosynthetic O2 evolution, and nitrogenase activity as per the prescribed protocol. Further, DNA microarray analysis was carried out using the Agilent platform. Results: NaCl stress adversely affected growth, photosynthetic O2 evolution, and nitrogenase activity of the wild-type Nostoc muscorum, while NaCl-resistant mutant remains unaffected under a given stress. Microarray data analysis identified 24 ORF related to the uptake of iron with fold regulation ?2 in the mutant strain. These ORFs belonging to the ABC-type ferric iron transporter that plays a significant role in the iron acquisition were identified in the mutant strain. Conclusion: The mechanism of iron homeostasis in the NaCl-resistant mutant has been explained. The results presented are essential to explain the regulatory role of the iron uptake system in stressed conditions.