Possibility of Bean yellow mosaic virus detection in Gladiolus plants by different methods

Journal of Plant Diseases and Protection - Serological and molecular methods were compared for the detection of Bean yellow mosaic virus (BYMV) in gladiolus plants. Plants showing mosaic symptoms...     

Carotenogenesis up-regulation in Scenedesmus sp. using a targeted metabolomics approach by liquid chromatography-high-resolution mass spectrometry

Carotenoids have potent antioxidant activity as well as therapeutic value, and their formation has been seen to be induced in algae by stress, including high-salt culture conditions. A differential profiling of carotenoids was conducted using a targeted metabolomics approach with accurate mass data generated by liquid chromatography-electrospray-time-of-flight (LC-ESI-TOF) mass spectrometry followed by postacquisition filtering based on isotope patterns and mass defects to detect carotenoids up-regulated in Scenedesmus sp. exposed to high-salt conditions. Algal cultures treated with high concentrations of sodium acetate or sodium chloride were found to cause an increase in various carotenoids. On the basis of differential analysis, astaxanthin and canthaxanthin increased upon salt treatment. Astaxanthin, in its free form and as fatty acid esters, was seen to increase in Scenedesmus sp. using accurate mass MS. A few other carotenoid compounds increased upon salt treatment, including echinenone and adonirubin, involved in the pathway of astaxanthin biosynthesis from β-carotene, as well as isomers of astaxanthin and canthaxanthin. A time course study of acetate treatment was done to observe the time-dependent up-regulation of carotenogenesis.     

Enhanced micropropagation of Dendrobium huoshanense C.Z. Tang et S.J. Cheng through protocorm-like bodies: The effects of cytokinins,carbohydrate sources and cold pretreatment

The effects of cytokinins, carbohydrate sources and cold pretreatment on the conversion of protocorm-like bodies (PLBs) to shoots were investigated for the enhancement of micropropagation of Dendrobium huoshanense C.Z. Tang et S.J. Cheng, an endangered medicinal plant in China. The effects of cytokinins and carbohydrate sources on the conversion of PLBs to shoots depended on their types and concentrations. The best results in terms of shoot development from PLBs occurred on 1/2 MS medium supplemented with 20 μM kinetin and 10 g l⁻¹ maltose. Cold pretreatment at 10 °C for 1–2 weeks significantly enhanced the conversion of PLBs to shoots, and over 1300 shoots were obtained from one gram of PLBs after 3 months of culture. The developed shoots were rooted on growth regulator-free MS medium supplemented with 8 g/l banana paste to give complete plantlets, which were successfully acclimatized with a survival rate of approximately 65%. The results indicate that a suitable cold pretreatment (10 °C for 1 week) followed by the use of 20 μM kinetin and 10 g/l maltose in 1/2 MS medium would produce a large number of shoots from PLBs for plantlet regeneration of D. huoshanense.     

Changes in the nutritional parameters of muscles of the common carp (Cyprinus carpio) and the silver carp (Hypophthalmichthys molitrix) following environmental exposure to cyanobacterial water bloom

The present study evaluated the effect of naturally developing cyanobacteria on the composition of muscles of two commercially important freshwater fish species. Fish were exposed to cyanobacterial biomass including Microcystis aeruginosa and Microcystis ichthyoblabe for 4 weeks. Then, they were transferred to dechlorinated potable water without any cyanobacteria for another 4-week period, thus modelling their preparation for consumers. Samples of muscles were collected every week during exposure and subsequent stay in dechlorinated potable water. The cyanobacterial water bloom of 3.9–6 × 10⁵ cells mL⁻¹ (133–383 μg g⁻¹ of total MC DW) induced statistically significant effects only in the content of fatty acids ( P <0.05; P <0.01) in the common carp ( Cyprinus carpio ), while all studied parameters including the content of dry matter and fat ( P <0.01), proteins ( P <0.05), fatty acid composition ( P <0.05; P <0.01) and some amino acids ( P <0.05) were affected in the silver carp ( Hypophthalmichthys molitrix ). This study has shown that cyanobacteria in the environment of commercially produced fish may decrease the dietetic value of fish muscles.     

Long temporal gradient of retrograde amnesia for a well-discriminated stimulus

This experiment tested the general validity of recent findings that retrograde amnesia can be produced by electroconvulsive shock only if the shock is administered within 10 to 30 seconds after the learning trial. Precautions were taken to avoid confusion of other shock effects with retrograde amnesia. A temporal gradient of elec- troconvulsive shock-produced retrograde amnesia, extending up to at least 1 hour, for a well-discriminated stimulus, was demonstrated in mice in a one-trial learning passive avoidance situation.     

Chiral fiber gratings

Chiral gratings with double helix symmetry were produced by twisting glass optical fiber with a noncircular core cross section as it passed through a miniature oven. We observed polarization-selective transmission in chiral fibers with pitches of tens of micrometers. Two modes of optical interaction were differentiated. In chirallong-period gratings, dips in transmission were observed at wavelengths associated with scattering into distinct cladding modes mediated by the chiral grating. In chiral intermediateperiod gratings, a broad scattering band was observed. These gratings can be used to produce sharp or broad polarization-selective filters.     

Cardiovascular actions of cadmium at environmental exposure levels

A low intake of dietary cadmium induces specific dose-dependent functional and biochemical changes in the cardiovascular tissues of rats. Maximum changes occur when the cadmium intake is 10 to 20 micrograms per kilogram of body weight per day. The changes reflect the accumulation of "critical" concentrations of cadmium in the cardiovascular tissues. The biologic activity of cadmium is demonstrated for intakes that approach those of the average American adult exposed to the usual environmental concentrations of the element but not to industrial concentrations. The sensitivity of the cardiovascular system to low doses of cadmium could not be anticipated by extrapolation from data on exposure to high concentrations of cadmium. The data support the hypothesis that ingested or inhaled environmental cadmium may contribute to essential hypertension in humans.