Pankaj Kumar

Bio: Pankaj Kumar is an academic researcher from Gurukul Kangri Vishwavidyalaya. The author has contributed to research in topics: Rhizosphere & Rhizobacteria. The author has an hindex of 7, co-authored 14 publications receiving 452 citations.

Inoculation of siderophore producing rhizobacteria and their consortium for growth enhancement of wheat plant

Abstract: This experiment has been designed to assess the effects of consortium and individual strain on growth promotion, biocontrol and nutrient uptake by wheat growing in Punjab. Fifteen rhizobacteria were isolated from rhizospheric soil of farmer's field of Punjab. Based on their ability to produce siderophore and strongly inhibition of phytopathogen (Fusarium solani), three potential plant growth promoting rhizobacteria (Aneurinibacillus aneurinilyticus WBC1, Aeromonas sp. WBC4 and Pseudomonas sp. WBC10) have been identified on the basis of phenotypic and genotypic (16S rRNA gene sequencing) characters. These three rhizobacteria are best in siderophore production and antagonistic property against F. solani. Consortium (WBC1+ WBC4+ WBC10) of three rhizobacteria significantly increased germination, root and shoot length and fresh and dry weight of wheat plant compared to single inoculation of any rhizobacteria and uninoculated control. It has been suggested that this consortium could be used for production of an effective bioinoculant for eco-friendly and sustainable production of wheat and other crops of Punjab. Consequently, we suggest to the farmers of Punjab to use this type of bioinoculants by replacing detrimental chemical fertilizers and pesticides (one of the leading cause of cancer in Punjab) and could regain their natural agro-ecosystem environment and again can be breadbasket of India. Indirectly the state of Punjab can be free from stigma of cancer state of India.

Effect of silver nanoparticles and Bacillus cereus LPR2 on the growth of Zea mays.

Abstract: The effect of Plant Growth Promoting Rhizobacteria (Bacillus sp.) and silver nanoparticles on Zea mays was evaluated. The silver nanoparticles were synthesized from Tagetes erecta (Marigold) leaf and flower extracts, whereas PGPR isolated from spinach rhizosphere. The silver nanoparticles (AgNPs) were purified using ultra centrifugation and were characterized using UV-Vis spectroscopy at gradient wavelength and also by High Resolution Transmission Electron microscopy (HRTEM). The average particles size of AgNPs was recorded approximately 60 nm. Almost all potential isolates were able to produce Indole Acetic Acid (IAA), ammonia and Hydrogen cyanide (HCN), solubilized tricalcium phosphate and inhibited the growth of Macrophomina phaseolina in vitro but the isolate LPR2 was found the best among all. On the basis of 16S rRNA gene sequence, the isolate LPR2 was characterized as Bacillus cereus LPR2. The maize seeds bacterized with LPR2 and AgNPs individually showed a significant increase in germination (87.5%) followed by LPR2 + AgNPs (75%). But the maximum growth of root and shoot of maize plant was observed in seeds coated with LPR2 followed by AgNPs and a combination of both. Bacillus cereus LPR2 and silver nanoparticles enhanced the plant growth and LPR2 strongly inhibited the growth of deleterious fungal pathogen. Therefore, LPR2 and AgNPs could be utilized as bioinoculant and growth stimulator, respectively for maize.

Effect of sediment and water quality parameters on the productivity of coastalshrimp farm

Abstract: The present study deals with the sediment and water characteristic of selected shrimp farms. The study envisaged to assess the sediment and water quality, productivity and fertility of the culture ponds and to understand the fluctuations in the values of sediment and water related parameters during the shrimp farming. Results have showed significant monthly variations at all four stations. Positive correlation was found between water temperature and salinity, salinity and primary productivity, primary productivity and dissolve oxygen, dissolve oxygen and nitrate, nitrate and total available phosphorous, soil salinity and soil organic carbon. However a negative correlation was observed between soil organic carbon and pH. Overall mean values of the nutrients in the sediment and water indicated that ponds are fertile and productive for shrimp culture operations.

Overview of the Antimicrobial Compounds Produced by Members of the Bacillus subtilis Group.

Abstract: Over the last seven decades, applications using members of the Bacillus subtilis group have emerged in both food processes and crop protection industries. Their ability to form survival endospores and the plethora of antimicrobial compounds they produce has generated an increased industrial interest as food preservatives, therapeutic agents and biopesticides. In the growing context of food biopreservation and biological crop protection, this review suggests a comprehensive way to visualize the antimicrobial spectrum described within the B. subtilis group, including volatile compounds. This classification distinguishes the bioactive metabolites based on their biosynthetic pathways and chemical nature: i.e., ribosomal peptides (RPs), volatile compounds, polyketides (PKs), non-ribosomal peptides (NRPs), and hybrids between PKs and NRPs. For each clade, the chemical structure, biosynthesis and antimicrobial activity are described and exemplified. This review aims at constituting a convenient and updated classification of antimicrobial metabolites from the B. subtilis group, whose complex phylogeny is prone to further development.

ACC Deaminase Producing Bacteria With Multifarious Plant Growth Promoting Traits Alleviates Salinity Stress in French Bean (Phaseolus vulgaris) Plants.

Abstract: Plant growth promoting rhizobacteria (PGPR) with 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity has the potential to promote plant growth and development under adverse environmental conditions. In the present study, rhizobacterial strains were isolated from Garlic (Allium sativum) rhizosphere and were screened in vitro ACC deaminase activity in DF salt minimal media supplemented with 3 mM ACC. Out of six isolates, two could degrade ACC into α-ketobutyrate, exhibiting ACC deaminase activity producing more than ∼1500 nmol of α-ketobutyrate mg protein-1 h-1, and assessed for other plant growth promoting (PGP) functions including indole acetic acid production (greater than ∼30 μg/ml), siderophore, Ammonia, Hydrogen cyanide production and inorganic Ca3(PO4)2 (∼85 mg/L) and ZnSO4 solubilization. Besides facilitating multifarious PGP activities, these two isolates augmented in vitro stress tolerance in response to 6% w/v NaCl salt stress and drought stress (-0.73 Mpa). The strains ACC02 and ACC06 were identified Aneurinibacillus aneurinilyticus and Paenibacillus sp., respectively on the basis of 16S rDNA gene sequence analysis and were evaluated for growth promoting potential in French bean seedlings under non-saline and salinity stress conditions through pot experiments. The seed bacterization by ACC02 and ACC06 revealed that treatment of plants with bacterial isolates in the form of consortia significantly declined (∼60%) stress stimulated ethylene levels and its associated growth inhibition by virtue of their ACC deaminase activity. The consortia treatment alleviated the negative effects of salinity stress and increased root length (110%), root fresh weight (∼45%), shoot length (60%), shoot fresh weight (255%), root biomass (220%), shoot biomass (425%), and total chlorophyll content (∼57%) of French bean seedlings subjected to salinity stress.

Influence of resistance breeding in common bean on rhizosphere microbiome composition and function

Abstract: The rhizosphere microbiome has a key role in plant growth and health, providing a first line of defense against root infections by soil-borne pathogens. Here, we investigated the composition and metabolic potential of the rhizobacterial community of different common bean (Phaseolus vulgaris) cultivars with variable levels of resistance to the fungal root pathogen Fusarium oxysporum (Fox). For the different bean cultivars grown in two soils with contrasting physicochemical properties and microbial diversity, rhizobacterial abundance was positively correlated with Fox resistance. Pseudomonadaceae, bacillaceae, solibacteraceae and cytophagaceae were more abundant in the rhizosphere of the Fox-resistant cultivar. Network analyses showed a modular topology of the rhizosphere microbiome of the Fox-resistant cultivar, suggesting a more complex and highly connected bacterial community than in the rhizosphere of the Fox-susceptible cultivar. Metagenome analyses further revealed that specific functional traits such as protein secretion systems and biosynthesis genes of antifungal phenazines and rhamnolipids were more abundant in the rhizobacterial community of the Fox-resistant cultivar. Our findings suggest that breeding for Fox resistance in common bean may have co-selected for other unknown plant traits that support a higher abundance of specific beneficial bacterial families in the rhizosphere with functional traits that reinforce the first line of defense.