This study discusses the possibilities of liquid silk (Silk gland silk) of Muga and Eri silk, the indigenous non mulberry silkworms of North Eastern region of India, as potential biomaterials. Silk protein fibroin of Bombyx mori, commonly known as mulberry silkworm, has been extensively studied as a versatile biomaterial. As properties of different silk-based biomaterials vary significantly, it is important to characterize the non mulberry silkworms also in this aspect. Fibroin was extracted from the posterior silk gland of full grown fifth instars larvae, and 2D film was fabricated using standard methods. The films were characterized using SEM, Dynamic contact angle test, FTIR, XRD, DSC, and TGA and compared with respective silk fibers. SEM images of films reveal presence of some globules and filamentous structure. Films of both the silkworms were found to be amorphous with random coil conformation, hydrophobic in nature, and resistant to organic solvents. Non mulberry silk films had higher thermal resistance than mulberry silk. Fibers were thermally more stable than the films. This study provides insight into the new arena of research in application of liquid silk of non mulberry silkworms as biomaterials.

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Plant growth promoting rhizobacteria (PGPR) exhibit an intricate and interdependent relationship with plants, which involves biotic and abiotic factors of the rhizosphere region other than the two partners. Success of PGPR is dependent on their survival and establishment on the root/rhizosphere. In this article, we have highlighted root colonization and celldensity dependant quorum sensing as the two important factors that play a key role in determining the outcome of the interaction.

Some fungi grow within plant parts and live as endosymbiont without causing apparent disease and enhance host growth, carrying defense response, nutrient acquisition, decrease biotic and abiotic stress, used as biofertilizer, also great role in medicine industry, known as endophytic fungi. Here five different fungi strains have been isolated from different plant parts of Plumbago zeylanica Linn. from the Departmental garden of Botany department of Burdwan university. These fungi strains show different plant growth traits like IAA production, Nitrogen fixation, phosphate solubilization, production of ammonia, polysaccharide, HCN, organic acid. These strains also can tolerate from different concentrations of salt. Among all fungal strains SL4 was identified as Colletotrichum sp. by 18S rRNA gene sequencing and gave the best result in most of the PGP traits of the fungal strains. Considering all these properties, SL4 strain can be used in agricultural field for cultivation of crops or in different nurseries as phytostimulator as well as biofertilizer.

Mature and healthy root nodules of Vigna mungo appeared to contain higher amount of indole-acetic acid (IAA) than non-nodulated roots. Dual effect of VAM fungus, Glomus fasciculatum and the nitrogen-fixing bacteria, Rhizobium sp. on the nodulation of roots of V. mungo was studied. It was recorded that the roots which were inoculated simultaneously with both the symbionts i.e., G. fasciculatum and Rhizobium exhibited greater amount of IAA production than the non-inoculated roots. A tryptophan pool present in the mature nodules and young leaves might serve as a precursor for IAA production in the roots and in the nodules. Activity of IAA-metabolizing enzymes, such as IAA oxidase, peroxidase, and polyphenol oxidase was investigated which indicates the active metabolism of IAA in roots and nodules. The Rhizobium symbiont isolated from fresh nodules of V. mungo produced significant amount of IAA under in vitro condition when tryptophan was added to the medium as precursor. Present study represents some beneficial effects of Rhizobium and G. fasciculatum on the production and metabolism of IAA in roots and nodules of V. mungo. The important physiological implication of the study on IAA production and its metabolism in Rhizobium-Legume-VAM tripartite symbiosis is certainly representing a new approach to satisfy the hormonal balance in the host plant.