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In this investigation, cellulose-degrading fungi and bacteria were isolated from different partially decomposed cellulose-rich substrates, such as groundnut residues, rice straw, and rotten wood, following dilution plating techniques on carboxymethyl cellulose agar media and screening for potential cellulose degradation ability. The development of a clear halo zone surrounding the microbial colonies during the initial screening process using the Congo red test (20 isolates) suggested cellulose hydrolysis, and the highest cellulase production activity was implied by the isolates with the largest clear zone ratio (9 isolates). Using both macroscopic and microscopic examinations, as well as standard biochemical tests outlined in Bergey’s Manual of Determinative Bacteriology, the genus-level identification of fungi and bacteria was accomplished. In order to molecularly identify the 4 isolated fungal and bacterial strains at the species level after being ultimately selected for cellulase production potential under in vitro studies, fungal and bacterial DNA was extracted and amplified by PCR using the universal primers ITS1 and ITS4 for fungi (ITS rRNA, 5.8S rRNA) and 8F and 1492R for bacterial isolates (16S rRNA). After sequencing, the PCR results were compared to other comparable sequences in GenBank (NCBI). Based on the available NCBI data, phylogenetic analysis of their ribosomal gene partial sequences revealed that DAJ2 (PP086700) shares 100% homology with Aspergillus foetidus, DTJ4 (PP086699) shares 99.74% similarity with Trichoderma atrobrunnium, DBJ6 (PP082584) shares 100% identity with Priestia megaterium, and DMB9 (PP082585) shares 99.88% homology with Micrococcus yunnanensis. The cellulolytic potential of Phanerochaete chrysosporium is well established. Therefore, it was considered a standard culture for comparison and was collected from the MTCC, Chandigarh, India. Overall, all 4 selected isolates and the check organism were mutually compatible or synergistic with each other, and their consortium is useful for the accelerated decomposition of organic constituents during rapid composting. [ABSTRACT FROM AUTHOR]

Peanut is mostly grown in calcareous soils with high pH which are deficient in available iron (Fe2+) for plant uptake causing iron deficiency chlorosis (IDC). The most pertinent solution is to identify efficient genotypes showing tolerance to limited Fe availability in the soil. A field screening of 40 advanced breeding lines of peanut using NRCG 7472 and ICGV 86031 as IDC susceptible and tolerant checks, respectively, was envisaged for four years. PBS 22040 and 29,192 exhibited maximum tolerance while PBS 12215 and 12,185 were most susceptible. PBS 22040 accumulated maximum seed resveratrol (5.8 ± 0.08 ppm), ferulic acid (378.6 ± 0.31 ppm) and Fe (45.59 ± 0.41 ppm) content. Enhanced chlorophyll retention (8.72–9.50 µg ml−1), carotenoid accumulation (1.96–2.08 µg ml−1), and antioxidant enzyme activity (APX: 35.9–103.9%; POX: 51- 145%) reduced the MDA accumulation (5.61–9.11 µM cm−1) in tolerant lines. The overexpression of Fe transporters IRT1, ZIP5, YSL3 was recorded to the tune of 2.3–9.54; 1.45–3.7; 2.20–2.32- folds respectively in PBS 22040 and 29,192, over NRCG 7472. PBS 22040 recorded the maximum pod yield (282 ± 4.6 g/row), hundred kernel weight (55 ± 0.7 g) and number of pods per three plants (54 ± 1.7). The study thus reports new insights into the roles of resveratrol, ferulic acid and differential antioxidant enzyme activities in imparting IDC tolerance. PBS 22040, being the best performing line, can be the potent source of IDC tolerance for introgression in high yielding but susceptible genotypes under similar edaphic conditions. [ABSTRACT FROM AUTHOR]

Archaea are unique microorganisms that are present in ecological niches of high temperature, pH and high salinity. Archaea may be present freely or associated with plant rhizosphere. The plant-microbe interactions may be implicit to plants adaptation to abiotic stress of hypersalinity. With an aim to look for population dynamics of archaea at different seasons of the year in hypersaline environments of Rann of Kutch, the rhizospheric, non-rhizospheric, water and sediment samples were collected during autumn, winter and summer. Sampling sites were selected on the basis of topography and vegetation which included barren land, salt pan and rhizosphere of monocot and dicot plants. Soil pH and salinity (mS cm−1) varied from 7.4–10.15 and 1.19–106.7 respectively. A total of 157 halophilic archaea were isolated using seven different selective media. The isolated archaeal were screened for abiotic stress and it has been found they show the wide range of in the tolerance to temperatures (25–65 °C), NaCl concentrations (0.86–5.48 M), water stresses (upto −0.75Mpa) and pH (4–10). The profiling of archaeal community using 16S rRNA gene sequencing and phylogenetic analysis revealed that all archaeal isolates belonged to a family halobacteriaceae of phylum euryarchaeota. Based on 16S rRNA gene sequencing the cultures were identified and belonged to twenty eight distinct species of 16 genera namely Haladaptatus, Haloarcula, Halobacterium, Halococcus, Haloferax, Halogeometricum, Halolamina, Halopenitus, Halorubrum, Halosarcina, Halostagnicola, Haloterrigena, Natrialba, Natrinema, Natronoarchaeum and Natronomonas. In the present study, seasonal and niche-specific archaea were reported and characterized from hypersaline environments. The haloarchaea with multifunctional plant growth promoting attributes, prevalent in the hypersaline environments must be colonizing the rhizosphere of plants and contributing to the growth and sustenance of plants. [ABSTRACT FROM AUTHOR]

Archaea are unique microorganisms that are present in ecological niches of high temperature, pH and salinity. A total of 157 archaea were obtained from thirteen sediment, water and rhizospheric soil samples collected from Rann of Kutch, Gujarat, India. With an aim to screen phosphate solubilizing archaea, a new medium was designed as Haloarchaea P Solubilization (HPS) medium. The medium supported the growth and P solubilization activity of archaea. Employing the HPS medium, twenty isolates showed the P-solubilization. Phosphate solubilizing archaea were identified as seventeen distinct species of eleven genera namely Haloarcula, Halobacterium, Halococcus, Haloferax, Halolamina, Halosarcina, Halostagnicola, Haloterrigena, Natrialba, Natrinema and Natronoarchaeum. Natrinema sp. strain IARI-WRAB2 was identified as the most efficient P-solubilizer (134.61 mg/L) followed by Halococcus hamelinensis strain IARI-SNS2 (112.56 mg/L). HPLC analysis detected seven different kinds of organic acids, namely: gluconic acid, citric acid, formic acid, fumaric acid succinic acid, propionic acid and tartaric acid from the cultures of these isolates. These phosphate solubilizing halophilic archaea may play a role in P nutrition to vegetation growing in these hypersaline soils. This is the first report for these haloarchaea to solubilize considerable amount of P by production of organic acids and lowering of pH. [ABSTRACT FROM AUTHOR]