Publications by authors named "Shobit Thapa"

Drought is a global phenomenon affecting plant growth and productivity, the severity of which has impacts around the whole world. A number of approaches, such as agronomic, conventional breeding, and genetic engineering, are followed to increase drought resilience; however, they are often time consuming and non-sustainable. Plant growth-promoting microorganisms are used worldwide to mitigate drought stress in crop plants.

View Article and Find Full Text PDF

Information on the role of boron (B) on soil physico-chemical and biological entities is scarce, and the precise mechanism in soil is still obscure. Present field investigation aimed to assessing the implication of direct and residual effect of graded levels of applied-B on soil biological entities and its concomitant impact on crop productivity. The treatments comprised of five graded levels of B with four replications.

View Article and Find Full Text PDF

Streptomyces is genetically and functionally diverse genus known to produce a wide array of phenolics and flavonoids with significant biotechnological applications. 52 isolates belonging to 26 species of Streptomyces collected from Meghalaya, India were analyzed for their genetic diversity using BOX-PCR. Significant inter- and intra- generic diversity was observed among the Streptomyces isolates especially those belonging to S.

View Article and Find Full Text PDF
Article Synopsis
  • Chitinases are enzymes that break down chitin and are found in all life forms, especially produced by bacteria and fungi for nutrition and as a means to parasitize other organisms.
  • Bacterial chitinases are particularly interesting due to their resilience in extreme conditions, making them useful in agriculture for pest control and in the seafood industry for managing waste.
  • Despite their potential, challenges such as low production rates hinder the widespread use of bacterial chitinases, prompting ongoing research to enhance their efficiency for industrial applications.
View Article and Find Full Text PDF

Cyanobacteria safeguard their photosynthetic machinery from oxidative damage caused by adverse environmental factors such as high-intensity light. Together with many photoprotective compounds, they contain myxoxanthophylls, a rare group of glycosidic carotenoids containing a high number of conjugated double bonds. These carotenoids have been shown to: have strong photoprotective effects, contribute to the integrity of the thylakoid membrane, and upregulate in cyanobacteria under a variety of stress conditions.

View Article and Find Full Text PDF

Accurate and timely disease detection plays a critical role in achieving sustainable crop protection. Globally, rice has been a staple crop for centuries plagued by the diseases that greatly hamper its productivity. Sheath rot, an emerging disease of rice caused by the seed-borne pathogen , has reportedly caused heavy losses to agricultural produce in recent years.

View Article and Find Full Text PDF

Cyanobacteria are ubiquitous photosynthetic prokaryotes responsible for the oxygenation of the earth's reducing atmosphere. Apart from oxygen they are producers of a myriad of bioactive metabolites with diverse complex chemical structures and robust biological activities. These secondary metabolites are known to have a variety of medicinal and therapeutic applications ranging from anti-microbial, anti-viral, anti-inflammatory, anti-cancer, and immunomodulating properties.

View Article and Find Full Text PDF

Medicinal and aromatic plants possess pharmacological properties (antidiabetes, anticancer, antihypertension, anticardiovascular, antileprosy, etc.) because of their potential to synthesize a wide range of therapeutic bioactive secondary metabolites. The concentration of bioactive secondry metabolites depends on plant species, local environment, soil type and internal microbiome.

View Article and Find Full Text PDF

Engineering diazotrophic rice having either an integral component of diazotrophic microbes or placing microbial origin nif gene to the rice plant is the dream of biotechnologist. Rice-Aeschynomene ecosystem of pristine chaur land provides a suitable niche to search Rhizobium endophytes in rice. Accordingly, the work was initiated to search suitable endophytic Rhizobium strain for artificial symbiosis within the roots of Desariya rice and its source through morphological, biochemical and molecular approaches.

View Article and Find Full Text PDF

Heavy metals (HMs) pose a global ecological threat due to their toxic effects on aquatic and terrestrial life. Effective remediation of HMs from the environment can help to restore soil's fertility and ecological vigor, one of the key Sustainable Development Goals (SDG) set by the United Nations. The cyanobacteria have emerged as a potential option for bioremediation of HMs due to their unique adaptations and robust metabolic machineries.

View Article and Find Full Text PDF

Azotobacter chroococcum (Az) and Trichoderma viride (Tv) represent agriculturally important and beneficial plant growth promoting options which contribute towards nutrient management and biocontrol, respectively. When Az and Tv are co-cultured, they form a biofilm, which has proved promising as an inoculant in several crops; however, the basic aspects related to regulation of biofilm formation were not investigated. Therefore, whole transcriptome sequencing (Illumina NextSeq500) and gene expression analyses were undertaken, related to biofilm formation vis a vis Tv and Az growing individually.

View Article and Find Full Text PDF
Article Synopsis
  • The severity of fungal diseases in rice plants is affected by nitrogen (N) availability and varies based on rice cultivar types (basmati vs. non-basmati).
  • Optimal N levels led to improved plant growth and higher levels of photosynthetic pigments and micronutrients, especially in susceptible varieties.
  • The interaction between the chosen rice varieties, the presence of the pathogen (Magnaporthe oryzae), and different N doses influenced both microbial communities in the phyllosphere and the plants' defense responses.
View Article and Find Full Text PDF
Article Synopsis
  • Rice paddies are unique ecosystems that support diverse microbial communities, influenced by water management and cultivation methods like DSR and SRI, which affect crop health and soil nutrients.
  • Research found significant differences in the rice leaf microbiome based on fertilizer use and cultivation methods, revealing diverse bacterial groups such as Bacillus and Pseudomonas.
  • Analyses showed that both the cultivation method and fertilizers notably altered the diversity and functioning of microbial communities on rice leaves, particularly affecting nitrogen and zinc levels.
View Article and Find Full Text PDF
Article Synopsis
  • The study investigated the bacterial communities on the leaves (phyllosphere) of seven rice genotypes, revealing that genotype P-44 had the highest pigment accumulation and CR-1009 and P-44 had the most diverse bacterial profiles.
  • A total of 60 distinct bacterial morphotypes were identified, with many showing biocontrol potential against rice pathogens such as Drechslera oryzae and Rhizoctonia solani.
  • Analysis highlighted that soil and leaf nutrient levels significantly affected bacterial abundance, which suggests that optimizing these nutrients could improve the effectiveness of foliar treatments for better plant growth and disease resistance.
View Article and Find Full Text PDF
Article Synopsis
  • Rice plants selectively associate with beneficial bacteria that enhance growth and help resist pathogens, with cyanobacteria like Calothrix elenkinii being highlighted as effective bioinoculants.
  • The study showed that inoculating rice with Calothrix led to significant increases in the population densities of beneficial culturable bacteria, including those capable of nitrogen fixation and phosphorus solubilization.
  • The findings also revealed that Calothrix inoculation improved rice plant growth, increased nitrogenase activity, and enhanced the overall metabolic activities and health of the plants, confirming its beneficial role in rice cultivation through synergistic interactions with the microbiome.
View Article and Find Full Text PDF