Screening for Multifarious Plant Growth Promoting and Biocontrol Attributes in Bacillus Strains Isolated from Indo Gangetic Soil for Enhancing Growth of Rice Crops.

Multifarious plant growth-promoting Bacillus strains recovered from rhizospheric soils of the Indo Gangetic plains (IGPs) were identified as Bacillus licheniformis MNNITSR2 and Bacillus velezensis MNNITSR18 based on their biochemical characteristics and 16S rDNA gene analysis. Both strains exhibited the ability to produce IAA, siderophores, ammonia, lytic enzymes, HCN production, and phosphate solubilization capability and strongly inhibited the growth of phytopathogens such as Rhizoctonia solani and Fusariun oxysporum in vitro. In addition, these strains are also able to grow at a high temperature of 50 °C and tolerate up to 10-15% NaCl and 25% PEG 6000. The results of the pot experiment showed that individual seed inoculation and the coinoculation of multifarious plant growth promoting (PGP) Bacillus strains (SR2 and SR18) in rice fields significantly enhanced plant height, root length volume, tiller numbers, dry weight, and yield compared to the untreated control. This indicates that these strains are potential candidates for use as PGP inoculants/biofertilizers to increase rice productivity under field conditions for IGPs in Uttar Pradesh, India.

Green synthesis of silver nanoparticles using methanolic fruit extract of Aegle marmelos and their antimicrobial potential against human bacterial pathogens.

Plant-based synthesis of nanoparticles has generated worldwide interest because of cost-effectiveness, eco-friendly nature and plethora of applications. In the present investigation, antimicrobial potential of silver nanoparticles (AgNPs) of methanolic extract of Aegle marmelos fruit has been investigated. Agar well diffusion method was used for determining antimicrobial activity of solvent extracts (viz., petroleum ether, chloroform, acetone, methanol and aqueous), and AgNPs. Among these, methanolic extract of A. marmelos showed highest inhibitory activity against B. cereus (16.17 ±â€¯0.50 mm) followed by P. aeruginosa (13.33 ±â€¯0.62 mm) and E. coli. Phytochemical analysis of methanolic extract of A. marmelos revealed the presence of tannins, saponins, steroids, alkaloids, flavonoids, and glycosides. AgNPs synthesized using A. marmelos methanolic extract, characterized by UV-Visible spectroscopy, atomic force microscopy, dynamic light scattering, and X-ray diffraction showed a peak at 436 nm and size ranged between 159 and 181 nm. Evaluation of the antimicrobial potential of green synthesized AgNPs recorded the highest inhibitory activity against B. cereus (19.25 ±â€¯0.19 mm) followed by P. aeruginosa (16.50 ±â€¯0.30 mm) and S. dysentriae. The minimum inhibitory concentration (MIC) of synthesized AgNPs was found to be in the range of 0.009875-0.0395 mg/100 µl which was quite lower than the MIC of crude extract i.e. 0.0781-0.3125 mg/100 µl. The results obtained indicated that the different crude extracts of A. marmelos plant as well as AgNPs have a strong and effective antimicrobial potential that provide a marvelous source for the development of new drug molecules of herbal origin which may be used for the welfare of humanity.