An inter-laboratory comparison of multi-enzyme and multiple substrate-induced respiration assays to assess method consistency in soil monitoring

The use of indicators in soil monitoring schemes to detect changes in soil quality is receiving increased attention, particularly the application of soil biological methods. However, to date, the ability to compare information from different laboratories applying soil microbiological techniques in broad-scale monitoring has rarely been taken into account. This study aimed to assess the consistency and repeatability of two techniques that are being evaluated for use as microbiological indicators of soil quality: multi-enzyme activity assay and multiple substrate-induced respiration (MSIR). Data were tested for intrinsic (within-assay plate) variation, inter-laboratory repeatability (geometric mean regression and correlation coefficient) and land-use discrimination (principal components analysis). Intrinsic variation was large for both assays suggesting that high replicate numbers are required. Inter-laboratory repeatability showed diverging patterns for the enzyme assay and MSIR. Discrimination of soils was significant for both techniques with relatively consistent patterns; however, combined laboratory discrimination analyses for each technique showed inconsistent correspondence between the laboratories. These issues could be addressed through the adoption of reliable analytical standards for biological methods along with adequate replication. However, until the former is addressed, dispersed analyses are not currently advisable for monitoring schemes.     

Colorimetric studies of benzoquinoline based hot brand monoazo reactive dyes and their dyeing performance on various fibers

A series of hot brand monoazo reactive dyes (9a-l) were obtained by the coupling of diazotized 1Hbenzo[ g]pyrazolo[3,4-b]quinoline-3-ylamine (5) with various cyanurated coupling components (8a-l) in good yield. Synthesized dyes were characterized by various spectroscopic techniques. Their dyeing performances as reactive dyes have been assessed on silk, wool, and cotton fabrics. The percentage dye bath exhaustion and fixation on different fibers were found to be very good. The dyed fabric showed moderate to very good light fastness and good to excellent washing and rubbing fastness properties. Spectral properties and colorimetric data of synthesized dyes have also been studied in detail.     

Evidence for the enhanced biodegradation of napropamide in soil

In laboratory incubations, the time to 50% loss of napropamide was approximately 60; 21 and 8 days in soil treated for the first, second and third time respectively. In a survey of soils from commercial fields, there was evidence that enhanced biodegradation of the compound had been induced by normal field applications—in some soils by a single previous treatment. Confirmation of the observations of rapid rates of loss in pre-treated soil was obtained in experiments with three formulations of napropamide. The rate of degradation in enhanced soils was unaffected by treatment of the soils with the antifungal antibiotic cycloheximide, but was inhibited by the antibacterial antibiotic chloramphenicol. Mixed bacterial cultures able to degrade the herbicide were obtained from three rapid-degrading soils by enrichment culture. Isolates from two of them were able to degrade the herbicide in pure culture. These bacteria have, as yet, not been characterised.     

Studies on antimicrobial activity for multidrug resistance strain by using phenyl pyrazolones substituted 3-(4-aminophenyl)-2-phenylquinazolin-4(3H)-one derivatives in vitro condition and their dyeing performance

Heterocyclic monoazo quinazolinone based azo dyes derived by the diazotization of 3-(4-aminophenyl)-2-phenylquinazolin-4(3H)-one with various phenyl pyrazolones based coupling components. All the heterocyclic azo dyes have been characterized by their percentage yield, UV-VIS spectroscopy, elemental analysis, IR spectroscopy, ¹H NMR spectroscopy, and dyeing performance on silk, wool, nylon, and polyester fibers. All the dyes gave moderate to excellent fastness properties on each fiber. The main focus was to synthesize heterocyclic monoazo dyes that give good dyeing property along with pharmacological activity (anti bacterial and antifungal). Therefore, the synthesized compounds were examined for their antimicrobial activity at various concentrations using well-known Kirby-Bauer disk diffusion method.     

Deep may not be meaningful: Cost and effectiveness of various ripping tine configurations in a plantation cultivation trial in eastern Australia

Deep ripping (subsoiling) is one of the more significant costs of establishing tree plantations on ex-pasture sites with compact soils. Ripping cost increases with depth, but the appropriate ripping depth required for successful tree establishment and growth is rarely clear. Tine modifications such as winged shanks and shallow leading tines have been shown to improve the work efficiency (volume soil loosened per unit drawbar pull) of deep ripping. We investigated whether increased work efficiency also translated to greater cost efficiency (volume soil loosened per unit cost), and whether additional depth and volume of loosened soil improved tree growth on a compact, medium clay, soil. We measured the operating costs for nine different ripping tine configurations, applied in conjunction with bed mounding, and compared early tree (Eucalyptus pilularis Sm.) growth and survival between the nine treatments and a no-cultivation control. Tine variations included presence or absence of wings, presence or absence of shallow leading tines, and depth (0.8 m, 0.6 m and 0.4 m). In most cases, increasing ripping depth or adding wings to the main tine increased operating cost but also tended to increase cost efficiency. The most cost efficient arrangement was for a winged main tine operating at 0.6 m with no leading tines. All cultivation treatments greatly enhanced survival and more than doubled growth to age 19 months compared to the control, but no cultivation treatment resulted in significantly better growth or survival than any other. Our provisional conclusion is that, when performed in conjunction with mounding, ripping beyond 0.4 to 0.6 m is not needed for satisfactory establishment on similar sites.     

Studies on a mixed bacterial culture from soil which degrades the herbicide linuron

A stable mixed bacterial culture which degrades the herbicide linuron was isolated from soil by enrichment with linuron in a liquid mineral medium. Radio-respirometry studies showed that the culture mineralised linuron completely. No intermediate degradation products were detected in the medium. The culture was able to utilise linuron as a source of both nitrogen and carbon and was also able to degrade the related herbicides monolinuron and chlorbromuron and the possible intermediate degradation products of linuron: 3,4-dichlorophenyl-l-methylurea, 3,4-dichlorophenylurea and 3,4-dichloroaniline. The culture was unable to degrade the 1,1-dimethyl substituted ureas monuron, diuron or metoxuron. The culture contained Gram-negative aerobic rods, and Gram-positive aerobic non-spore-forming rods and cocco-bacilli. Of 124 isolates from the mixed culture, none degraded linuron in pure culture, indicating that a consortium of organisms is involved. Further investigation suggested that Pseudomonas spp. were important components of the population responsible for degradation.     

Genetic diversity and differentiation of <Emphasis Type="Italic">Helicoverpa armigera</Emphasis> nuclear polyhedrosis virus isolates from India

India has a rich biodiversity of microbes. Soil is the major source for isolation of entomopathogens, after the infected insects themselves. Four isolates of Helicoverpa armigera nuclear polyhedrosis virus (HearNPV) were obtained from the samples collected one each from Anand, Surat and Junagadh of Gujarat and Patancheru of Andhra Pradesh. All the HearNPV isolates appeared as clear, irregular six-sided objects with rounded edges, phase-bright under phase contrast. Junagadh, Surat, Patancheru and Anand isolates gave 27.47–42.80%, 36.83–51.32%, 26.05–43.76% and 42.99–54.85% mortality, respectively, when the percent mortality was pooled over period. The least number of HearNPV polyhedral inclusion bodies (PIBs) (5.1 × 10⁷) of the Anand isolate were required to kill 50% of the H. armigera population within 120 h. The Anand isolate was fastest (90.30 h), followed by Surat (120.26 h), Junagadh (139.53 h) and Patancheru (143.10 h) in killing 50% of the H. armigera population at a dose of 10⁹ PIBs ml⁻¹. RAPD analysis of all 15 arbitrary oligonucleotide primers generated 353 scorable bands with 201 loci. A total of 181 polymorphic bands were obtained, ranging in size from 141 to 1,873 base pairs. The percentage of polymorphic loci was 90.19%. The mean polymorphism information content (PIC) value for 15 primers was found to be 0.99. The similarity coefficient values based on 15 RAPD markers ranged from 0.235 to 0.407. The four isolates were grouped into two clusters: one cluster consisted of Junagadh and Anand and the second cluster consisted of Surat and Patancheru.