Ishwar Prakash Sharma

Physiological and biochemical changes in tomato cultivar PT-3 with dual inoculation of mycorrhiza and PGPR against root-knot nematode

Arbuscular mycorrhizal fungi (AMF) and plant growth promoting rhizobacteria (PGPR) have potential to control soil-borne diseases including plant-parasitic nematodes. First, the effects of dual inoculation of mycorrhiza (Rhizophagus irregularis) and two stains of pseudomonads (Pseudomonas jessenii strain R62 and Pseudomonas synxantha strain R81) on tomato (Solanum lycopersicum cv. PT-3) growth were tested. Further, the physiological and biochemical changes caused by these beneficial organisms during infection by the root-knot nematode Meloidogyne incognita were studied. The experiment was conducted under glass house conditions and carried out up to one month after nematode inoculation. Plants treated with dual or individual inoculation of AMF and PGPR showed significantly enhanced plant growth and reduced nematode infection. In addition, they exhibited potent activity of phenolics (28xa0%) and defensive enzymes i.e. peroxidase (PO; 1.26 fold), polyphenyloxidase (PPO; 1.35 fold) and superoxide dismutase (SOD; 1.09 fold) while a significant reduction in malondialdehyde (MDA; 1.63 fold) and hydrogen peroxide (H2O2; 1.30 fold) content was recorded when compared to the nematode-infected plants. These findings indicate the feasibility of AMF and PGPR individually or in combinations as potential biocontrol agents for the management of root-knot nematodes.

Bryophytes: Hoard of remedies, an ethno-medicinal review

Bryophytes are the second largest group of land plants after angiosperms. There is very less knowledge available about medicinal properties of these plants. Bryophytes are popular remedy among the tribal people of different parts of the world. Tribal people use these plants to cure various ailments in their daily lives. Bryophytes are used to cure hepatic disorders, skin diseases, cardiovascular diseases, used as antipyretic, antimicrobial, wound healing and many more other ailments by different tribal communities of Africa, America, Europe, Poland, Argentina, Australia, New Zealand, Turkey, Japan, Taiwan, Pakistan, China, Nepal and different parts of South, North and Eastern India. Apart from ethno-medicinal uses some bryophytes possesses antitumor activities against different cancer cell lines and this property of bryophytes needs to be more focused in the future. Compile information about medicinal properties and anticancer properties of bryophytes is lacking till date. In the present review, the authors tried to compile all the ethno-medicinal and other related information of bryophytes and fill the knowledge lacuna in this particular field. Some published reviews are available but the information is segregated. This manuscript will help people doing research in the bryophytes.

PGPR: Heart of Soil and Their Role in Soil Fertility

Soil is an excellent niche for the growth of microorganisms which includes plant growth-promoting rhizobacteria (PGPRs). PGPRs have great potential for plant growth promotion as they control pest and disease and have been considered important in sustainable agriculture. PGPRs induce and/or synthesize various growth-promoting and biocontrolling chemicals which are useful for sustainable agriculture and environment. These chemicals are phytohormones, antibiotics, enzymes, etc., which react with the soil and provide better health to the plants. PGPRs directly or indirectly circulate their products to soil for better soil health which further enhance the soil immunity followed by influencing plant growth, productivity, and yield. Soil immune system works strongly by the activities of soil microbes which are considered as a heart of soil. These soil microbes are responsible for increasing soil fertility and productivity which are considered important for sustainable agriculture.

Application of arbuscular mycorrhiza for managing root-knot disease in tomato (Lycopersicon esculentum) under glass-house conditions in Pantnagar, India

Root-knot disease caused by Meloidogyne spp. poses a worldwide threat to agriculture as well as environment due to excess use of chemical nematicides for its management. Recently, arbuscular mycorrhizal fungi (AMF) have achieved importance as biocontrol agent for the managements of root-knot disease. In this aspect, the present study was focused on the effect of AMF (Glomus intraradices) against root-knot disease of tomato (Lycopersicon esculentum) caused by Meloidogyne incognita. Observations of G. intraradices against M. incognita were taken at 10, 20 and 30 days after M. incognita second stage juveniles (J2) inoculation on tomato roots, which were pre-colonized by G. intraradices. A significant effect was observed on plant growth (length and biomass) and nematode induced (root galls, egg masses, egg and adult females) parameters in nematode inoculated G. intraradices colonized plants as compared to non-colonized plants at all the three harvesting periods. The finding of present study indicates the potential of G. intraradices as a potential biocontrol tool for the management of root-knot disease and can be used in the place of environmentally hazardous chemical nematicides. n n Key words:xa0Arbuscular mycorrhiza, root-knot disease, nematicides, biocontrol, management.

Impact of arbuscular mycorrhizal fungus, Glomus intraradices , Streptomyces and Pseudomonas spp. strain on finger millet ( Eleusine coracana L.) cv Korchara under water deficit condition

In present study, a total of 104 bacteria and 96 actinomycetes were isolated from rhizosphere plant rootxa0of finger millet (E leusine coracana ) from Almora district of Uttarakhand, India. Isolates werexa0characterized using microscopic and morphological methods followed by their biochemical test. Basedxa0on functional tests, four most promising isolates were identified using 23S rDNA primers asxa0 Streptomyces labedae (SB-9), Streptomyces flavofuscus (SA-11), and 16S rDNA primers asxa0 Pseudomonas poae (KA-5), and Pseudomonas fluorescens (KB-7). Influence of Glomus intraradices xa0(G.I.) singly and along with actinomycetes and Pseudomonas spp. were evaluated under irrigated andxa0water deficit conditions. Out of eight treatments studied in this study, a higher significant increase inxa0plant height with S. labedae SB-9 + G.I and P. poae KA-5 + G.I were recorded. In well watered and waterxa0deficient conditions, maximum shoot dry matter content was recorded in P. Poae + P. flurosence + G.Ixa0and S. labedae + S. flavofuscus + G.I inoculated plants in comparison to their respective control. Under xa0in vitro condition, P. poae KA-5 produced higher amount of indole acetic acid (IAA) among the selectedxa0isolates. Anti-oxidant enzyme, superoxide dismutase (SOD) and accumulation of free proline content inxa0leaves were maximum in P. Poae + G.I inoculated plants under water deficit condition. In the presence ofxa0 Streptomyces and Pseudomonas spp. a better mycorrhizal infection was observed in treated plantxa0roots. This investigation support mutual symbiosis of Streptomyces and Pseudomonas strains with G.xa0intraracides which had synergic effect on finger millet cv. Korchara plant under irrigated as well asxa0under water stress condition. Keywords: Glomus intraradices , Streptomyces , Pseudomonas , anti oxidants, plant growth promotion, IAAxa0production

Elucidating stress proteins in rice (Oryza sativa L.) genotype under elevated temperature: a proteomic approach to understand heat stress response

Rice is one of the widely consumed staple foods among the world’s human population. Its production is adversely affected by high temperature and is more pronounced at flowering stage. Elucidating elevated temperature stress-related proteins as well as associated mechanisms is inevitable for improving heat tolerance in rice. In the present study, a proteomic analysis of heat-sensitive rice genotype, IET 21405 was conducted. Two-dimensional electrophoresis (2-DE) and MALDI-TOF/MS-based proteomics approaches revealed a total of 73 protein spots in rice leaf. The protein profiles clearly indicated variations in protein expression between the control and heat treated rice genotypes. Functional assessment of 73 expressed proteins revealed several mechanisms thought to be involved in high temperature including their putative role in metabolism, energy, protein synthesis, protein transport/storage, etc. Besides these, some proteins are expected to involve in photosynthesis, tricarboxylic acid (TCA) cycle, glycolysis and other proteins for energy production. The proteins identified in the present study provide a strong basis to elucidate gene function of these proteins and to explain further the molecular mechanisms underlying the adaptation of rice to high temperature stress.

Correction to: Mycorrhizal colonization and phosphorus uptake in presence of PGPRs along with nematode infection

The article Mycorrhizal colonization and phosphorus uptake in presence of PGPRs along with nematode infection, written by Ishwar Prakash Sharma and A. K. Sharma, was originally published electronically on the publisher’s internet portal (currently SpringerLink) on 20 September 2018 with open access.

Mycorrhizal colonization and phosphorus uptake in presence of PGPRs along with nematode infection

Arbuscular mycorrhiza (AM), plant growth promoting rhizobacteria (PGPRs) and root-knot nematode survive in the rhizosphere and perform the same niche. AM and PGPRs play positive role in roots while nematode oppose it. Nematode damages the root system, which reduces the nutrient uptake specially phosphorus (P) while AM help to uptake. PGPRs are another symbiotic micro-organism helpful to mycorrhizal survival and colonization. AM and PGPRs can defeat the soil borne diseases like root-knot disease which lead to increasing mycorrhizal colonization and nutrient uptake. On this basis current work emphasizes the effects on mycorrhizal colonization and P uptake in presence of PGPRs along with root-knot nematode infection in tomato plants.