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Wheat dwarf virus (WDV, genus Mastrevirus, family Geminiviridae) has a wide host range among Poaceae (Vacke, 1961). Grass species such as Briza media, Poa pratensis, Poa compressa, Bothriochloa ischaemum, Brachypodium pinnatum, Anthoxanthum odoratum, Agrostis capillaries, Phleum pretense, Dactylis glomerata, Lolium perenne, Trisetum flavescens, Cynosurus cristatus, Deschampsia cespitosa, Alopecurus pratensis, Arrhenatherum elatius, Poa trivialis, Apera spicaventi, Elymus caninus, Festuca arundinacea, Bromus inermis, Elytrigia repens and Echinochloa crus-galli were tested for the evaluation of the host range of two WDV strains: WDVW and WDV-B. Three seedlings of each grass species were exposed to adults of viruliferous leafhopper vector Psammotetix alienus which were removed from the plants after three weeks. Subsequently, non-viruliferous P. alienus were left for acquisition feeding on the infected grass species for seven days, and were then transferred to healthy wheat and barley plants. The leafhoppers from the grasses inoculated by the WDV-W and WDV-B were transferred to wheat and barley plants, respectively. Samples from grasses and cereals (wheat and barley) were collected 30 and 70 days post inoculation, respectively, for WDV detection by DAS-ELISA (Sediag, France). WDV was detected in two A. spica-venti and C. cristatus plants inoculated by each of the WDV strains and in one L. perenne plant inoculated by WDV-W, as well as in wheat and barley plants. The rest of the grass species remained virus-free. Hence, our results confirm two earlier reported WDV hosts, i.e L. perenne (Vacke, 1971) and A. spica-venti (Vacke and Cibulka, 1999) and identify C. cristenus as a new WDV host. To the best of our knowledge this is the first report of C. cristanus as a host and potential reservoir of WDV in agroecosystems. [ABSTRACT FROM AUTHOR]

A quantitative PCR, real-time RT-PCR, and one-step real-time RT-PCR using SYBR Green-based tools for reliable detection and relative quantitation of Prune dwarf virus (PDV) in stone fruits are described. The assay reliability was tested on 55 samples from different hosts and regions. The sensitivity of the assay was also compared with other assays with different primers. Two plant-expressed genes, actin and 18S rRNA, were used as housekeeping genes for accurate quantitation of PDV in stone fruit trees. The expression of the gene for actin and the 18S ribosomal RNA gene corresponded with each other accurately, with standard deviation values of 1.905 cycles on average, 1.36 for Prunus persica, and 2.45 for other Prunus species tested. The results of this study support the need to use more than one housekeeping gene as an internal control to avoid possible errors caused by unstable internal control gene mRNA expression when quantifying the extent of PDV infection., (Copyright (c) 2009 Elsevier B.V. All rights reserved.)

Analgesic, antiinflammatory and CNS depressant activities of four sesquiterpenes, viscosumic acid, viscozulenic acid, viscoazucine and viscoazulone, and a flavonoid glycoside, quercetin-3-O-(6''-feruloyl)-beta-D-galactopyranoside isolated form the aerial parts of Polygonum viscosum (Polygonaceae) have been assessed. All test compounds exhibited CNS depressant activity in open field test, all but viscoazulone showed analgesic activity in Eddy's hot plate test, all sesquiterpenes inhibited acetic acid induced abdominal writhing in mice, and all but viscoazucine and the flavonoid glycoside exhibited mild to moderate antiinflammatory effect on carrageenan induced rat paw edema.

A rapid and effective RNA release procedure (RNA-RP) for detection of the Apple stem pitting virus (ASPV) and the Apple stem grooving virus (ASGV) in woody plants by reverse transcription-polymerase chain reaction (RT-PCR) was developed. RNA-RP released RNA into crude homogenate. RNA-RP was compared with classical phenol/chlorophorm extraction of RNA. The RT-PCR detection of ASPV and ASGV was shown to be similar by both the RNA preparation procedures. RNA-RP in contrast to the classical phenol/chloroform procedure represents a reliable and easy-to hand protocol convenient for routine virus detection. Leaf tissues, especially dormant bud leaves and leaves during blossom, were shown to be the most optimal material for detection of these viruses, irrespective of the used RNA preparation procedure.

The polymerase chain reaction (PCR) assay was successfully used to identify Cydia pomonella granulovirus (CpGV) in larvae of Cydia pomonella L. (codling moth). PCR with the primers CpGV-2A/CpGV-2B and CpGV-3A/CpGV-3B was found suitable for detection of CpGV. The primers Cp-I/Cp-II and Cp-III/Cp-IV were able to identify the transposable element TCp3.2 in C. pomonella larvae. The presence of CpGV in the larvae from orchards,which had been infected with CpGV was tested during 2 years post infection. (p.i.). CpGV was found in as many as 15% of the surviving larvae 1 year p.i. in one location. The virus was not detected in CpGV-infected orchards 2 years p.i. or in natural C. pomonella populations. This result suggests a poor persistence of CpGV in surviving C. pomonella individuals and its slow spread in a natural host population. One the other hand, the presence of a transposable element, transposon TCp3.2 may correlate with virus redistribution in this insect population.

A new sesquiterpene, 1,4-dimethoxycarbonyl-7-(1-methylethyl)- 3,3a,6,7,8,8a-hexahydroazulene (viscoazucine) (1), and a known flavone, 3',5,7-trihydoxy-3,4',5'-trimethoxyflavone (4), have been isolated from Polygonum viscosum. The structures of these compounds were elucidated by spectroscopic analyses, notably UV, MS and NMR.

The isolation and NMR spectral data of epifriedelanol from Vitis trifolia are reported. It demonstrated antitumor activity in a potato disc bioassay.