Studies on bacteriological quality of nainital lake water in different seasons

The total coliform and E. coli load of Nainital lake water in different seasons has been studied. The variation of these organisms with season, rainfall and human activities in the catchment area were observed.     

Susceptibility of betanodavirus in a newly established vertebra-derived cell line from Mosquitofish (Gambusia affinis)

In the present study, a new cell line from the vertebra of mosquitofish Gambusia affinis was successfully established and characterized. The cell line is named as bone Gambusia affinis (BGA) and subcultured for more than 55 passages in Leibovitz's/L15 medium supplemented with 15% FBS at 28°C. The cell line has a modal chromosome number of 48. Molecular characterization of the partial sequence of the coi gene confirmed the origin of the BGA cell line from mosquitofish. These cells exhibited epithelial morphology confirmed by the cytokeratin marker. The BGA cells showed mineralization of their extracellular matrix when stained with alizarin red and von Kossa stain. BGA cells were found to be susceptible to RGNNV and SJNNV strains of betanodavirus (NNV) showing cytopathic effect with multiple vacuolations in the cells. The RT-PCR confirmed the betanodavirus infections in BGA cells. The SEM micrograph showed the morphological changes observed in the cell during virus infection. The in vivo challenge experiment also showed the viral replicating efficiency in the Gambusia affinis with increasing viral titre. Thus, our present results show that the BGA cell line is a useful tool for isolating betanodavirus and could be used to investigate bone cell differentiation and extracellular matrix mineralization.     

The effects of high CO2 pre-storage treatments and rate of establishment of controlled atmosphere conditions on bitter pit and bruise susceptibility of ‘Bramley’s Seedling’ apples

Summary

Bitter pit incidence in Bramley apples that were cooled prior to either slow (three weeks) or rapid (one day) establishment of controlled atmosphere (CA) conditions (9% CO₂, 12% O₂) was 14.7 and 3.2% respectively. Bruise susceptibility was also reduced by rapid CA establishment although the rate of fruit softening was unaffected. The control of bitter pit by pre-storage treatment with 15–25% CO₂ for one to three weeks was no better than by rapid establishment of CA, although bruise susceptibility was further reduced by some treatments. Some pre-storage treatments caused injury to the apple skin and flesh (brownheart). The extent to which fruits were injured was dependent on CO₂ concentration and the duration of CO₂ treatment. There was some evidence that early picked fruit not cooled prior to CO₂ treatment was more severely injured both internally and externally by CO₂ than that harvested later and cooled prior to treatment.     

Tyrosinase-Immobilized MCM-41 for the Detection of Phenol

In the present investigation, we report the immobilization of the enzyme tyrosinase on mesoporous silica material, i.e. MCM-41 to serve as a tool for the detection of phenol. The enzyme immobilized onto the MCM-41 matrix has shown to retain its activity and is quite stable. The immobilization of enzyme has been discussed, and the various factors that affect the loading of enzyme onto MCM-41 were studied and optimized. The applicability of tyrosinase-immobilized MCM-41 was then demonstrated for the detection of phenol. The lowest detectable concentration of phenol by tyrosinase-immobilized MCM-41 was observed to be 1 mg l⁻¹. The factors influencing the detection of phenol were then studied in detail.     

Effect of root competition and shade on survival and growth of nine woody plant taxa within a pecan [Carya illinoinensis (Wangenh.) C. Koch] alley cropping system

Suitability for production of woody floral stems in a pecan [Carya illinoinensis (Wangenh.) C. Koch] alley cropping was determined for nine shrub species in northwest Florida. Treatments included partial shade without root competition, partial shade with root competition, and full sun. Only three species had high rates of survival for all treatments throughout both years of the study: Callicarpa americana L. (American beautyberry), C. americana var. Lactea (white American beautyberry), and Crataegus marshallii Eggl. (parsley haw). For C. americana, plant growth index increased through time and was similar among the three treatments, indicating that this species grew equally well in sun or shade irrespective of root competition from the tree crop. C. americana var. Lactea had similarly high rates of survival and grew largest in partial shade without root competition (81.7?cm) compared to partial shade with root competition (67.2?cm) and full sun (57.0?cm). C. marshallii had 100 % survival in partial shade without root competition, with one mortality in partial shade with root competition (91.7 % survival) and one in full sun (91.7 % survival). Growth index did not increase over time and was similar among all three treatments. Other species tested had low rates of survival in all treatments throughout both years of the study and included: Ilex glabra L. (inkberry), Ilex myrtifolia Walt. (myrtle-leaf holly), Hydrangea paniculata Seibold var. ??Tardiva?? (panicle hydrangea), Hydrangea quercifolia Bart. (oakleaf hydrangea), Lyonia lucida (Lam.) K. Koch, and Salix matsudana Koidz. F. tortuosa Rehd. (corkscrew willow). No species produced sufficient flowers, fruits or ornamental stems during this establishment period to allow a florist evaluation of the stems for use as woody floral stems.     

Variation in transpiration efficiency and its related traits in a groundnut (Arachis hypogaea L.) mapping population

Transpiration efficiency (TE) has been recognized as an important source of yield variation under drought stress in groundnut. Here the variation for TE is evaluated in a set of 318 recombinant inbred lines (RILs) of groundnut at F₈ generation, derived from a cross between a high TE (ICGV 86031) and a low TE (TAG 24) parent, and the value of specific leaf area (SLA), SPAD chlorophyll meter readings (SCMR) and carbon isotope discrimination (Δ¹³C) as surrogates of TE are measured. Transpiration efficiency was measured gravimetrically in the 318 RILs and parents under progressive soil drying in a pot culture in two post-rainy seasons. Large and consistent variation for TE existed among the RILs across years. The overall distribution of TE among the RILs indicated that TE was governed by dominant and additive genes. Surrogates SLA and SCMR, were measured prior, during and after completion of the drought period, whereas Δ¹³C was measured on the dried tissue after harvest. Transpiration efficiency was negatively associated with SLA after the completion of stress treatment (r² = 0.15) and Δ¹³C in leaves (r² = 0.13) and positively associated with SCMR during stress (r² = 0.17). These associations, all fairly weak, were significant only in 2004. None of these relationships was found in 2005. Although the heritability of SCMR during 2005 was relatively higher than that of TE, and although SCMR has previously been used to identify contrasting germplasm for TE, the stress-dependence of the relationship with TE, and the poor regression coefficients (r²) with that RIL population, do not confer that these surrogates are adequately robust enough in that population. Though more time consuming, a direct gravimetric evaluation for TE appeared to be more reliable.     

Molecular characterization of Desmodium species — An important ingredient of ‘Dashmoola’ by RAPD analysis

Identification of medicinal plants by their molecular signature is a fast growing tool. The identification of Desmodium gangeticum (L.) DC. (Shalparni, a constituent of Ayurvedic formulation “Dashmoolarishtha”) was carried out using genomic approach. Authentic samples of D. gangeticum(L.) DC., D. velutinum (Willd.) DC. and D. triflorum (L.) DC. were analyzed and compared to commercial samples of various origin. Within twenty primers used, eleven gave 223 RAPD fragments. RAPD profiles of three species showed very low similarity index (0.21–0.39), whereas market samples showed high similarity of 0.82–0.89 with authenticated D. gangeticum.     

Antiviral activity of sulfated polysaccharides from Sargassum ilicifolium against fish Betanodavirus infection

Sulfated polysaccharides (SP) from seaweeds exhibit numerous biological activities and are less toxic than conventional antiviral drugs. However, little is known about their mode of action. This study aims at extracting the polysaccharides from brown seaweed Sargassum ilicifolium and then evaluating its antiviral activity against fish Betanodavirus. The extracted SP was characterized through FT-IR, ¹H NMR, and thermal gravimetric analysis (TGA). The antiviral activity of SP was tested on SGA cell line by syncytia reduction and the polysaccharide represented a prominent antiviral activity to Betanodavirus by reducing the cytopathic effect (CPE) formation in vitro. The study revealed that SP effectively blocked viral attachment and entry. Moreover, during the in vivo challenge experiment in Gambusia affinis, SP treatment showed a significant decrease in the viral titers. Hence, these results indicate that the polysaccharides obtained from S. ilicifolium exhibited the high antiviral potential to Betanodavirus infection in fishes both in vitro and in vivo.

     

Genetic closeness of Zanskari and Spiti ponies of India inferred through microsatellite markers

The Zanskari and Spiti ponies were characterized for genetic variation using a set of 25 equine microsatellite markers. The DNA was isolated from the 42 blood samples of Zanskari and 32 blood samples of Spiti ponies collected from their respective breeding tracts. The DNA was amplified by polymerase chain reaction at the studied microsatellite loci and amplified product was resolved for alleles by denaturing urea-polyacrylamide gel electrophoresis. The allelic frequency data so obtained was statistically analyzed using POPGENE computer program. The PCR product size-range varied from 84 to 102 at locus HTG6 to 238 to 244 at locus UCDEQ425. The observed number of alleles ranged from four to nine with a mean (± standard deviation) of 5.80 ± 1.32 alleles per locus in Zanskari and 5.40 ± 1.04 alleles per locus in Spiti ponies. The mean observed heterozygosity was found to be 0.61 ± 0.06 and 0.56 ± 0.09 for Zanskari and Spiti ponies, respectively. The Nei's standard and unbiased genetic distance were found to be 0.11 and 0.09, respectively, indicating close genetic relatedness of Zanskari and Spiti ponies.