Municipal wastewater treatment plants (MWWTPs) are a milieu for co-occurrence of multiple antibiotic resistance genes (ARGs). This facilitates mixing and genetic exchange; and promotes dissemination of multidrug resistance (MDR) to wastewater bacterial communities which is hazardous for the effluent receiving environment. This study investigated the co-occurrence of extended-spectrum beta-lactamase (ESBL) genes (bla, bla, bla, bla), and integron-integrase genes (intI1, intI2, intI3) in MDR bacteria isolated from the Bharwara MWWTP in Lucknow, India.
View Article and Find Full Text PDFSoil contaminants threaten global food security by posing threats to food safety through food chain pollution. Fly ash is a potential agent of soil contamination that contains heavy metals and hazardous pollutants. However, being rich in macro- and micronutrients that have direct beneficial effects on plant growth, fly ash has been recommended as a low-cost soil ameliorant in agriculture in countries of the Global South.
View Article and Find Full Text PDFDistillery spent wash (DSW) from molasses-based distilleries is being used as a low-cost alternative to chemical fertilizers in countries like India and Brazil. However, using DSW as a fertilizer substitute causes organic pollutant leaching, including melanoidins and caramel colourants that turn bodies of water dark brown. This study investigated the arbuscular mycorrhiza (AM) mediated degradation of organic pollutants in DSW.
View Article and Find Full Text PDFWe investigated the role of plant host and soil variables in determining arbuscular mycorrhizal fungi (AMF) community composition in plant roots of two spatially separated mangrove estuaries on the rivers Aghanashini (14° 30' 30″ N-74° 22' 44″ E) and Gangavali (14° 35' 26″ N-74° 17' 51″ E) on the west coast of India. Both mangrove estuaries had similar plant species composition but differed in soil chemistries.We amplified a 550-bp portion of 18S small subunit (SSU) rDNA from mangrove plant roots and analysed it by restriction fragment length polymorphism (RFLP).
View Article and Find Full Text PDFThe gharial (Gavialis gangeticus Gmelin) is a fish-eating specialist crocodylian, endemic to south Asia, and critically endangered in its few remaining wild localities. A secondary gharial population resides in riverine-reservoir habitat adjacent to the Nepal border, within the Katerniaghat Wildlife Sanctuary (KWS), and nests along a 10 km riverbank of the Girwa River. A natural channel shift in the mainstream Karnali River (upstream in Nepal) has reduced seasonal flow in the Girwa stretch where gharials nest, coincident with a gradual loss of nest sites, which in turn was related to an overall shift to woody vegetation at these sites.
View Article and Find Full Text PDFArbuscular mycorrhizal fungi (AMF) and plant growth-promoting rhizobacteria inhabit the plant rhizosphere. Both functional groups can influence plant community structures, and interactions between them can vary from being synergistic to antagonistic. HCN-producing Pseudomonas protegens CHA0 is a plant growth-promoting rhizobacterium.
View Article and Find Full Text PDFEctomycorrhizal (EM) fungi form symbioses with dominant tree families in boreal, temperate and tropical ecosystems and are important drivers of ecosystem function. EM fungal hyphae extend over a large area making them susceptible to enhanced radiation levels from naturally occurring or anthropogenically originating radioisotopes in the rhizosphere. In this study, the in-vitro effects of ionizing radiation on the growth and biomass of EM fungi Suillus luteus, S.
View Article and Find Full Text PDFSubstantial amounts of nutrients are lost from soils through leaching. These losses can be environmentally damaging, causing groundwater eutrophication and also comprise an economic burden in terms of lost agricultural production. More intense precipitation events caused by climate change will likely aggravate this problem.
View Article and Find Full Text PDFLong-lived radionuclides such as (90)Sr and (137)Cs can be naturally or accidentally deposited in the upper soil layers where they emit β/γ radiation. Previous studies have shown that arbuscular mycorrhizal fungi (AMF) can accumulate and transfer radionuclides from soil to plant, but there have been no studies on the direct impact of ionizing radiation on AMF. In this study, root organ cultures of the AMF Rhizophagus irregularis MUCL 41833 were exposed to 15.
View Article and Find Full Text PDFMultiple species of arbuscular mycorrhizal fungi (AMF) can colonize roots of an individual plant species but factors which determine the selection of a particular AMF species in a plant root are largely unknown. The present work analysed the effects of drought, flooding and optimal soil moisture (15-20 %) on AMF community composition and structure in Sorghum vulgare roots, using PCR-RFLP. Rhizophagus irregularis (isolate BEG 21), and rhizosphere soil (mixed inoculum) of Heteropogon contortus, a perennial C4 grass, collected from the semi-arid Delhi ridge, were used as AMF inocula.
View Article and Find Full Text PDFPseudomonas fluorescens CHA0 has been shown to suppress the growth of a wide range of microbial plant pathogens as well as invertebrate pests such as root nematodes. Hydrogen cyanide, a secondary metabolite produced by the bacterium, has been credited as being one of the determinants of its biocontrol ability. The use of biocontrol agents against social insect pests such as termite Odontotermes obesus has limitations because of behavioural adaptations that include (1) removal of the pathogen when grooming by the termites and (2) isolation of infested members of the colony.
View Article and Find Full Text PDFThe subterranean termite Odontotermes obesus is an important pest of the Indian subcontinent, causing extensive damage to major agricultural crops and forest plantation trees. Control of termites by strategies employing their parasites has limitations because they have evolved a complex social structure, immune responses, and adaptive behavior toward pathogen-infected individuals. Nonparasitic rhizobacteria that produce harmful metabolites might facilitate the biocontrol of termites.
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