Biosurfactant from Bacillus sp. A5F Reduces Disease Incidence of Sclerotinia sclerotiorum in Soybean Crop.

The present study was conducted to assess the biocontrol activity of biosurfactants obtained from Bacillus species A5F. The variables significantly influencing the production of biosurfactants under in vitro conditions were further optimized using response surface methodology. Optimal values of selected culture variables, i.

Retraction Note to: Ecological Significance of Microdiversity: Coexistence Among Casing Soil Bacterial Strains Through Allocation of Nutritional Resource.

[This retracts the article DOI: 10.1007/s12088-011-0068-7.].

Draft Genome Sequence of the Plant Growth-Promoting Rhizobacterium Pseudomonas protegens Strain BNJ-SS-45, Isolated from Rhizosphere Soil of Wheat (Triticum aestivum).

Here, we present the draft genome sequence of Pseudomonas protegens strain BNJ-SS-45, which was isolated from wheat rhizosphere. The genome is assembled with 7,116,445 bp with a GC content of 63.34% consisting of 32 scaffolds.

Thermophilic molds: Biology and applications.

Thermophilic molds thrive in a variety of natural habitats including soils, composts, wood chip piles, nesting materials of birds and other animals, municipal refuse and others, and ubiquitous in their distribution. These molds grow in simple media containing carbon and nitrogen sources and mineral salts. Polyamines are synthesized in these molds and the composition of lipids varies considerably, predominantly containing palmitic, oleic and linoleic acids with low levels of lauric, palmiotoleic and stearic acids.

Characterization of an antifungal compound produced by Bacillus sp. strain A(5) F that inhibits Sclerotinia sclerotiorum.

A potential antagonist, Bacillus sp. strain A(5) F was isolated from soybean rhizosphere following in vitro dual plate screening. The bacterium displayed strong inhibitory activity in vitro against soybean stem rot pathogen, Sclerotinia sclerotiorum.

Ecological significance of microdiversity: coexistence among casing soil bacterial strains through allocation of nutritional resource.

A combination of cultivation-based methods with a molecular biological approach was employed to investigate whether bacteria with identical 16S rRNA gene sequences can represent distinct eco- and genotypes. A set of eight bacterial strains wherein three were Pseudomonas putida and rest were Acinetobacter calcoaceticus, were isolated from casing soils community by conventional plating. These strains had identical 16S rRNA gene sequences and represented the dominant phylotype in the plateable fraction.

Selection of plant growth-promoting Pseudomonas spp. that enhanced productivity of soybean-wheat cropping system in Central India.

The aim of this investigation was to select effective Pseudomonas sp. strains that can enhance the productivity of soybean-wheat cropping systems in Vertisols of Central India. Out of 13 strains of Pseudomonas species tested in vitro, only five strains displayed plant growth-promoting (PGP) properties.

Shelf-life enhancement of bio-inoculant formulation by optimizing the trace metals ions in the culture medium for production of DAPG using fluorescent pseudomonad R62.

Statistical experimental design was used to optimize the concentration of trace elements for production of antifungal compound, 2,4-diacetylphloroglucinol (DAPG), from fluorescent pseudomonad R62 in shake-flask cultivation. The selection of the trace metal ions, influencing DAPG production, was done using Plackett-Burman design (PBD). Only Zn(2+), Mn(2+) and MoO(4)(2-) were the most significant components (p<0.

Evaluation of in situ functional activity of casing soils during growth cycle of mushroom (Agaricus bisporus (Lange) Imbach) employing community level physiological profiles (CLPPs).

Community level physiological profiles (CLPPs) have been rarely applied to mushroom compost ecosystem, probably for the lack of standardized methodology. Recently, however CLPPs have been employed as a tool to investigate the degree of maturity of compost (Mondini and Insam, 2005, Compost Science and Utilization, 13(1): 27-33). The potential of CLPPs to detect compost maturity test is considerably significant in that it provides sensitivity and the simplicity of the assay.

Impact of antifungals producing rhizobacteria on the performance of Vigna radiata in the presence of arbuscular mycorrhizal fungi.

Plant growth-promoting rhizobacteria (PGPR) that produce antifungal metabolites are potential threats for the arbuscular mycorrhizal (AM) fungi known for their beneficial symbiosis with plants that is crucially important for low-input sustainable agriculture. To address this issue, we used a compartmented container system where test plants, Vigna radiata, could only reach a separate nutrient-rich compartment indirectly via the hyphae of AM fungi associated with their roots. In this system, where plants depended on nutrient uptake via AM symbiosis, we explored the impact of various PGPR.

Interactions of Bacillus spp. and plants--with special reference to induced systemic resistance (ISR).

Biological control of soil-borne pathogens comprises the decrease of inoculum or of the disease producing activity of a pathogen through one or more mechanisms. Interest in biological control of soil-borne plant pathogens has increased considerably in the last few decades, because it may provide control of diseases that cannot or only partly be managed by other control strategies. Recent advances in microbial and molecular techniques have significantly contributed to new insights in underlying mechanisms by which introduced bacteria function.

Metagenomics: Future of microbial gene mining.

Modern biotechnology has a steadily increasing demand for novel genes for application in various industrial processes and development of genetically modified organisms. Identification, isolation and cloning for novel genes at a reasonable pace is the main driving force behind the development of unprecedented experimental approaches. Metagenomics is one such novel approach for engendering novel genes.

Antimycobacterial serratamolides and diacyl peptoglucosamine derivatives from Serratia sp.

The cyclodepsipeptide serratamolide A ( 1) and five closely related compounds together with three new glucosamine derivatives were isolated by bioactivity-guided chromatography from the XAD adsorber resin extract of a Serratia sp. The structures of the compounds were elucidated by 2D NMR and MS analyses. In addition to the known serratamolide A ( 1) with two C 10 alkyl chains, its derivatives always contained one C 10 chain combined with either C 12:1, C 12, C 11, C 9, or C 8 chains.

Induced systemic resistance (ISR) in plants: mechanism of action.

Plants possess a range of active defense apparatuses that can be actively expressed in response to biotic stresses (pathogens and parasites) of various scales (ranging from microscopic viruses to phytophagous insect). The timing of this defense response is critical and reflects on the difference between coping and succumbing to such biotic challenge of necrotizing pathogens/parasites. If defense mechanisms are triggered by a stimulus prior to infection by a plant pathogen, disease can be reduced.

Molecular characterization of plant growth promoting rhizobacteria that enhance peroxidase and phenylalanine ammonia-lyase activities in chile (Capsicum annuum L.) and tomato (Lycopersicon esculentum Mill.).

Pythium and Phytophthora species are associated with damping-off diseases in vegetable nurseries and reduce seedling stand and yield. In this study, bacterial isolates were selected on the basis of in vitro antagonism potential to inhibit mycelial growth of damping-off pathogens along with plant growth properties for field assessment in wet and winter seasons. We demonstrate efficacy of bacterial isolates to protect chile and tomato plants under natural vegetable nursery and artificially created pathogen-infested (Pythium and Phytophthora spp.

Rhamnolipids from the rhizosphere bacterium Pseudomonas sp. GRP(3) that reduces damping-off disease in Chilli and tomato nurseries.

A detailed screening of bacterial isolates from the Central Himalayan region for plant growth promotion and antimycelial activity against Pythium and Phytophthora strains afforded seven isolates, of which three were particularly effective against the incidence of damping-off in field trials on chilli and tomato. In this investigation an initial spectroscopic survey of the methanolic extracts of the seven bacterial isolates showed complex mixtures except for Pseudomonas sp. GRP3, one of the most promising isolates on the basis of field studies.

Rhizosphere Pseudomonas sp. strains reduce occurrence of pre- and post-emergence damping-off in chile and tomato in Central Himalayan region.

Based on in vitro screening for PGP and anti-mycelial activity against three zoosporic pathogenic oomycetes, Pythium aphanidermatum 123, P. aphanidermatum 4746, and Phytophthora nicotianae 4747, seven bacterial isolates were selected for field trials on tomato and chile to test for plant growth promotion under natural and artificial disease-infested field sites in both winter and wet seasons. The effectiveness of isolates in the field trials correlated with the in vitro antagonism screening data.

Plant growth-promoting Pseudomonas sp. Strains reduce natural occurrence of anthracnose in soybean (Glycine max L.) in central Himalayan region.

Biological control is an accepted important component of current plant disease management strategies. Introduction of bacterized seeds carrying bacterial isolates with proven growth-promotion capabilities and antagonistic characteristics offer a valid alternative to chemical protectants. Root colonization of disease-susceptible (PS 1024) and moderately resistant (PS1042) varieties of soyabean (Glycine Max L) by fluorescent pseudomonad (FLPs) strains GRP3, PEn-4, PRS1, and WRS-24 was studied in relation to natural occurrence of anthracnose caused by Colletotrichum dematium (Pers Ex Fr.

Growth promoting influence of siderophore-producing Pseudomonas strains GRP3A and PRS9 in maize (Zea mays L.) under iron limiting conditions.

Maize seeds were bacterized with siderophore-producing pseudomonads with the goal to develop a system suitable for better iron uptake under iron-stressed conditions. Siderophore production was compared in fluorescent Pseudomonas spp. GRP3A, PRS9 and P.

Rhizobacterial diversity in India and its influence on soil and plant health.

The rhizosphere or the zone of influence around roots harbors a multitude of microorganisms that are affected by both abiotic and biotic stresses. Among these are the dominant rhizobacteria that prefer living in close vicinity to the root or on its surface and play a crucial role in soil health and plant growth. Both free-living and symbiotic bacteria are involved in such specific ecological niches and help in plant matter degradation, nutrient mobilization and biocontrol of plant disease.

Combat of iron-deprivation through a plant growth promoting fluorescent Pseudomonas strain GRP3A in mung bean (Vigna radiata L. Wilzeck).

Microorganisms and plants sustain themselves under iron-deprived conditions by releasing siderophores. Among others, fluorescent pseudomonads are known to exert extensive biocontrol action against soil and root borne phytopathogens through release of antimicrobials and siderophores. In this study, production and regulation of siderophores by fluorescent Pseudomonas strain GRP3A was studied.

Purification of alpha-amylase isoenzymes from Scytalidium thermophilum on a fluidized bed of alginate beads followed by concanavalin A-agarose column chromatography.

An alpha-amylase has been purified from the thermophilic fungus Scytalidium thermophilum. A ninefold purification was achieved in a single step using fluidized bed chromatography wherein alginate was used as the affinity matrix. There are at least two isoenzymes as shown by concanavalin A (Con A)-agarose column chromatography.

Comparative behaviour of yeast strains for ethanolic fermentation of culled apple juice.

The culled apple juice contained (% w/v): nitrogen, 0.036; total sugars, 11.6 and was of pH 3.

Formation and activities of xylanhydrolysing enzymes of Humicola grisea var thermoidea.

A thermophilic fungus, Humicola grisea var thermoidea, produced in liquid culture two endoxylanases (1,4-β-D-xylan-xylanohydrolase, EC 3.2.1.