Activity of spinosad on stored-tobacco insects and persistence on cured tobacco stripst

Every year raw tobacco and manufactured tobacco products are lost to two major storage pests, the cigarette beetle, Lasioderma serricorne (F) and the tobacco moth, Ephestia elutella (Hiibner). Post-harvest management of both insects is achieved through sanitation, insect monitoring and fumigation with phosphine. However, insect resistance to phosphine and control failures have been reported, and fumigants are under constant regulatory pressure. Here we report the evaluation of spinosad, a bioinsecticide derived from the fermentation of the soil micro-organism Saccharopolyspora spinosa Mertz & Yao. Spinosad was first registered in 1997 and is now widely used as a field pest control agent on many crops, including tobacco. The insecticidal activity of the fermentation product (technical spinosad, TS) was measured by diet incorporation assays against L serricorne and E elutella larvae. Mortality levels were determined on newly hatched larvae and over the whole insect life cycle. For both species, no emergence of adult insects was observed in cured tobacco sprayed with 50mg TS kg(-1) and inoculated with eggs or newly hatched larvae. These results indicated that spinosad has potential for the control of both species in stored tobacco, since 100% control of both pests could be achieved at 50 mg TS kg(-1), and with almost full control (90-95%) at 10 mg kg(-1). We also monitored the stability of the product on cured tobacco. The original concentration of the main active component of TS, spinosyn A, did not change significantly over 18 months, indicating no loss of spinosad during a typical leaf storage period of time. Bioassays against larvae confirmed that the bioinsecticidal activity of spinosad was retained.     

Molecular characterization of <Emphasis Type="Italic">Xiphinema brevicollum</Emphasis> (Nematoda: Longidoridae) from the Czech Republic

Populations of Xiphinema brevicollum occurring in the Czech Republic were described morphologically and molecularly. Published species-specific primer set BL18 and BV3 was used to amplify three populations of X. brevicollum from the Czech Republic. These primers were tested against 9 species of Xiphinema and 11 species of Longidorus. Amplification was also observed for X. inaequale, X. italiae and X. lambertii. Three additional markers, mitochondrial cytochrome c oxidase subunit 1, ribosomal D2/D3 expansion segment of the 28S gene and 18S gene, were amplified and sequenced for X. brevicollum, X. inaequale and X. lambertii belonging to X. americanum-group. Comparison of cox1 sequences of X. brevicollum from the Czech Republic with X. taylori from the Slovak Republic (accession number AM086702) suggested that these populations represent the same species.     

An AFLP-based assessment of the genetic diversity within Hibiscus rosa-sinensis and its place within the Hibiscus genus complex

Species within the genus Hibiscus (Malvaceae) are herbaceous or woody plants, annuals or perennials. Within the genus, most of the domesticated species are grown as ornamentals, and the most widely exploited is Hibiscus rosa-sinensis, which is particularly variable with respect to flower colour and shape. H. rosa-sinensis is thought to have originated following hybridization between two species complexes endemic to different geographic locations.     

Dietary Supplementation of Oregano and Sage Dried Leaves on Performances and Meat Quality of Rabbits

The aim of this research was to evaluate the dietary supplementation 1% （w/w） of oregano and sage dried leaves on performances and meat quality of broiler rabbits. A feeding trial, which lasted 48 d, was carried out on 105 male Bianca Italiana rabbits randomly divided in seven groups and fed ad libitum. At the end of the trial ten animals per group were slaughtered and samples of dorsal muscle were taken in order to perform laboratory analysis. Mortality rate did not statistically differ between groups. Growth performances of animals fed diets supplemented with aromatic plants were higher （P〈0.05） than those of animals of control group, whereas carcass parameters were not affected by treatments excepting for the slaughter weight that showed the same trend as growth performances. Meat quality traits, oxidative lipid stability and fatty acid proifle were not inlfuenced by aromatic plant supplementation. In conclusion, oregano and sage in form of dried leaves can be used in rabbit without adverse effects on performance, carcass characteristics and meat quality traits.     

Campylobacter jejuni in the red squirrel (Sciurus vulgaris) population of Southern Italy

Rectal swab samples were collected from 60 red squirrels (Sciurus vulgaris) from July 2006 to April 2007 in Southern Italy. Samples were tested for Campylobacter jejuni and C. coli by culture methods and suspected colonies were then confirmed by polymerase chain reaction. C. jejuni was detected in 5/60 (8.3%) samples examined but infection status was not related to age or sex and C. coli was not isolated. This is believed to be the first report of C. jejuni infection in the red squirrel.     

Phenolic constituents and antioxidant activity of Wendita calysina leaves (Burrito), a folk Paraguayan tea

Burrito tea originates from the leaves of Wendita calysina, an indigenous Paraguayan plant, which is commonly consumed in South America and in Western countries. Phytochemical investigation of this species has led to the isolation of 14 constituents, among them 2 new flavanonols, dihydroquercetagetin (1) and 3,5,6,7,4'-pentahydroxyflavanonol (2), in addition to several known methoxyflavones, methoxyflavonols, phenylethanoid glycosides, and benzoic acid derivatives (4-14). All structures were elucidated by ESI-MS and NMR spectroscopic methods. Quantitative determination of phenolic constituents from burrito water infusions has been performed by HPLC-UV-DAD. The total antioxidant activity of the tea was measured by the ABTS(*)(+) radical cation decolorization and chemiluminescence (CL) assays and compared with the values of other commonly used herbal teas (green and black teas, mate, and rooibos).     

Investigations on the promoting effect of ammonium hydrogencarbonate on the formation of acrylamide in model systems

NH4HCO3 is known to promote acrylamide formation in sweet bakery products. This effect was investigated with respect to sugar fragmentation and formation of acrylamide from asparagine and sugar fragments in model systems under mild conditions. The presence of NH4HCO3 led to increases in acrylamide and alpha-dicarbonyls from glucose and fructose, respectively. As compared to glucose or fructose, sugar fragments such as glyoxal, hydroxyethanal, and glyceraldehyde formed much higher amounts of acrylamide in reaction with asparagine. The enhancing effect of NH4HCO3 is explained by (1) the action of NH3 as base in the retro-aldol reactions leading to sugar fragments, (2) facilitated retro-aldol-type reactions of imines in their protonated forms leading to sugar fragments, and (3) oxidation of the enaminols whereby glyoxal and other reactive sugar fragments are formed. These alpha-dicarbonyl and alpha-hydroxy carbonyl compounds may play a key role in acrylamide formation, especially under mild conditions.     

Seasonal variation in carbon isotopic composition of bog plant litter during 3 years of field decomposition

In this study, we describe the seasonal variation in ¹³C abundance in the litter of two Sphagnum species and four vascular plant species during 3 years of field decomposition in an Italian alpine bog. Litter bags were periodically retrieved at the end of summer and winter periods, and the δ¹³C in residual litter was related to mass loss, litter chemistry, and climatic conditions. In Sphagnum litter, higher rates of decomposition during summer months were associated with an increase of δ¹³C probably due to the incorporation of microbial organic compounds rich in ¹³C in the residual litter. In the litter of Eriophorum vaginatum, Carex rostrata and Calluna vulgaris, we observed a decrease of δ¹³C with an increase in the concentration of lignin-like compounds. The residual litter of Potentilla erecta showed a decrease of ¹³C abundance during the first 2 years, but on proceeding the decomposition, the δ¹³C increased again probably reflecting the incorporation of microbial organic compounds.     

Pollen morphology as fertility predictor in hybrid tea roses

Fertility of hybrid tea roses is often reduced due to their interspecific origin but also to intensive inbreeding. New genotypes used as pollen donors represent an economic risk for a breeding programme, as their influence on seed production is unknown. In this study 11 cut rose genotypes were selected from a company database as high fertile or low fertile male parents, according to the number of seeds per hybridisation. Pollen morphology and in vitro germination of the selected genotypes were characterised. Pollen was either small (mean diameter <30 μm), shrunken, and irregular (abnormal), or large (mean diameter >30 μm), elliptical and crossed by furrows (normal). High correlations were found between the number of seeds produced per hybridisation and the pollen diameter (r = 0.94) or the percentage of normal pollen (r = 0.96). In order to evaluate the predictive power of the models, we conducted regression analyses and performed a validation experiment on genotypes not present in the database and without background information on fertility. Pollen diameter and percentage of normal pollen were characterised and fitted in the regression models for seed set predictions. Validation with an independent dataset gave a good prediction for 83.3% of the data. This indicates that using either the mean pollen diameter or the percentage of normal pollen resulted in effective fertility prediction. This tool could enhance the genetic variability in crossings between hybrid tea roses, thus creating possibilities for less economically risky exploitation of new tetraploid genotypes as male parents.