Multivariate analysis and genetic diversity for morphometric and root textural quality traits in ashwagandha (Withania somnifera Dunal)

Ashwagandha (Withania somnifera) is an important medicinal plant and its dried roots are used in traditional systems of medicine. The market price of roots is determined by physical (textural) quality. Brittle roots with high starch and low fiber are considered to be superior because of ease in grinding. Genetic diversity studies based on root textural parameters have not been done so far. So the present study was designed to assess genetic diversity for morphometric traits and root textural quality parameters among two morphologically distinct groups: Poshita and Nagore. The PCA separated the morphometric and root texture variables distinctly into two different principal components: PC-1 and PC-2 respectively, indicating that both are negatively associated. All the morphotypes in Poshita group showed high positive loadings in PC-1 indicating that component genotypes are high root yielding. Nagore morphotypes were low yielding but the root texture was good. Clustering of morphotypes grouped Poshita and Nagore separately with high inter-cluster distances indicating that both groups are highly divergent from each other, suggesting that there is sufficient scope for varietal improvement through hybridization.     

Giant piezoelectricity on Si for hyperactive MEMS

Microelectromechanical systems (MEMS) incorporating active piezoelectric layers offer integrated actuation, sensing, and transduction. The broad implementation of such active MEMS has long been constrained by the inability to integrate materials with giant piezoelectric response, such as Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) (PMN-PT). We synthesized high-quality PMN-PT epitaxial thin films on vicinal (001) Si wafers with the use of an epitaxial (001) SrTiO(3) template layer with superior piezoelectric coefficients (e(31,f) = -27 ± 3 coulombs per square meter) and figures of merit for piezoelectric energy-harvesting systems. We have incorporated these heterostructures into microcantilevers that are actuated with extremely low drive voltage due to thin-film piezoelectric properties that rival bulk PMN-PT single crystals. These epitaxial heterostructures exhibit very large electromechanical coupling for ultrasound medical imaging, microfluidic control, mechanical sensing, and energy harvesting.     

Characterizing rangeland vegetation using Landsat and 1-mm VLSA data in central Wyoming (USA)

As an alternative to ground-cover data collection by conventional and expensive sampling techniques, we compared measurements obtained from very large scale aerial (VLSA) imagery for calibrating moderate resolution Landsat data. Using a grid-based sampling scheme, 162 VLSA images were acquired at 100 m above ground level. The percent vegetation cover in each photo was derived using SamplePoint (a manual inventory method) and VegMeasure (a reflectance based, automated method). Approximately two-thirds of the VLSA images were used for calibrating Landsat data while the remainder was used for validation. Regression models with Landsat bands accounted for 55% of the VegMeasure-based measurements of vegetation, whereas models that included both Landsat bands and elevation data accounted for 67%. The relationship between the Landsat bands and the percent vegetation cover measured by SamplePoint was lower (R ² = 20%), highlighting the differences between the inventory and reflectance based protocols. Results from the model validation indicated that the model’s predictive power was lower when the vegetation cover was either <20% or >55%. Additional work is needed in these ecosystems to improve the calibration techniques for sites with low and high vegetation cover; however, these results demonstrate the VLSA imagery could be used for calibrating Landsat data and deriving rangeland vegetation cover. By adopting such methodologies the US Federal land management agencies can increase the efficiency of the monitoring programs in Wyoming and in other western states of the US. Mention of trade names is for information only and does not imply endorsement by USDA over comparable products or services.     

Environmental exposure to residues after aerial spraying of endosulfan: residues in cow milk,fish, water,soil and cashew leaf in Kasargode,Kerala, India

A detailed study has been conducted to evaluate the residues of endosulfan and its principal metabolite (alpha-endosulfan, beta-endosulfan and endosulfan sulfate) which may have accumulated in environmental samples due to regular aerial spray application of endosulfan on cashew leaf plantation for a period of 20 years. Three months after the last spray of endosulfan 350 g litre-1 EC at 300 ml acre-1 (equivalent to 105 g AI acre-1 = 42.5 g ha-1), a total of 93 samples of cow milk, fish, water, soil and dried cashew leaf were collected from a village in Kasargode District, Kerala, India, where endosulfan contamination was likely to have occurred. All the samples were analyzed for total residues of endosulfan (comprising alpha- and beta-endosulfan), endosulfan sulfate and also the potential hydrolysis product endosulfan diol, using gas chromatography with electron capture detection. The minimum detection limits of total endosulfan was 0.001 microgram g-1. Analysis of soil samples showed the deposition of total endosulfan residues in the range < 0.001-0.010 microgram g-1, and dried leaf samples showed residues of endosulfan in the range < 0.001-3.43 micrograms g-1 dry weight. In cow milk, fish and water, endosulfan residues could not be detected above the minimum detection limit. Endosulfan diol was not observed in any sample. The data obtained was confirmed by GC-MS-EI using selective ion monitoring (SIM) mode.     

Reduced cerebral infection of Neospora caninum in BALB/c mice vaccinated with recombinant Brucella abortus RB51 strains expressing N. caninum SRS2 and GRA7 proteins

Neospora caninum, an obligate intracellular protozoan parasite, is the causative agent of bovine neosporosis, an important disease affecting the reproductive performance of cattle worldwide. Currently there is no effective vaccine available to prevent N. caninum infection in cattle. In this study, we examined the feasibility of developing a live, recombinant N. caninum vaccine using Brucella abortus vaccine strain RB51 as the expression and delivery vector. We generated two recombinant RB51 strains each expressing SRS2 (RB51/SRS2) or GRA7 (RB51/GRA7) antigens of N. caninum. BALB/c mice immunized by single intraperitoneal inoculation of the recombinant RB51 strains developed IgG antibodies specific to the respective N. caninum antigen. In vitro stimulation of splenocytes from the vaccinated mice with specific antigen resulted in the production of interferon-gamma, but not IL-5 or IL-10, suggesting the development of a Th1 type immune response. Upon challenge with N. caninum tachyzoites, mice vaccinated with strain RB51/SRS2, but not RB51/GRA7, showed significant resistance to cerebral infection when compared to the RB51 vaccinated mice, as determined by the tissue parasite load using a real-time quantitative TaqMan assay. Interestingly, mice vaccinated with either strain RB51 or RB51/GRA7 also contained significantly lower parasite burden in their brains compared to those inoculated with saline. Mice vaccinated with strain RB51/SRS2 or RB51/GRA7 were protected to the same extent as the strain RB51 vaccinated mice against challenge with B. abortus virulent strain 2308. These results suggest that a recombinant RB51 strain expressing an appropriate protective antigen(s), such as SRS2 of N. caninum, can confer protection against both neosporosis and brucellosis.     

Potentiation of malathion by other insecticides against Musca domestica

Twenty-seven insecticides, including organochlorine, organophosphorus compounds and carbamates were tried for potentiation of the toxic effect of malathion. Carbaryl, diazinon, fenthion, gamma-BHC, parathion and tetrachlorvinphos potentiated the action of malathion. Fourteen insecticides gave additive effects while seven proved antagonistic. Insecticides which showed potentiation, were further tested by mixing with malathion in the ratios of 1:9, 3:7, 5:5, 7:3 and 9:1. All the five combinations in the six mixtures gave potentiating effects. Maximum potentiation of 17.6 times was observed in 1:9 combination of malathion and gamma-BHC. The proportions in which the insecticides were mixed had a pronounced effect on the toxic effect of malathion.     

Antibacterial activity of Terminalia pallida

The methanol extract of the dried fruit powder of Terminalia pallida was evaluated for antimicrobial activity. The methanol extract showed a broad spectrum of antibacterial activity.     

Genetic Diversity in Colletotrichum gloeosporioides from Stylosanthes spp. at Centers of Origin and Utilization

ABSTRACT Using molecular markers, this work compares the genetic diversity in Colletotrichum gloeosporioides infecting species of the tropical forage legume Stylosanthes at the center of origin in Brazil and Colombia with that of Australia, China, and India, where Stylosanthes spp. have been introduced for commercial use. There was extensive diversity in the pathogen population from Brazil, Colombia, China, and India. The Australian pathogen population was least diverse probably due to its geographical isolation and effective quarantine. The extensive diversity in China and India means that threats from exotic pathogen races to Stylosanthes pastures can potentially come from countries outside the South American center of origin. In Brazil and India, both with native Stylosanthes populations, a high level of genetic differentiation in the pathogen population was associated with sites where native or naturalized host population was widely distributed. There was limited genetic diversity at germplasm evaluation sites, with a large proportion of isolates having identical haplotypes. This contrasts recent pathogenicity results for 78 of the Brazilian isolates that show hot spots of complex races are more common around research stations where host germplasm are tested, but few are found at sites containing wild host populations. For a pathogen in which the same races arise convergently from different genetic backgrounds, this study highlights the importance of using both virulence and selectively neutral markers to understand pathogen population structure.