Floral ontogeny of <Emphasis Type="Italic">Schisandra chinensis</Emphasis> (Schisandraceae): implications for androecial evolution within <Emphasis Type="Italic">Schisandra</Emphasis> and <Emphasis Type="Italic">Kadsura</Emphasis>

The organogenesis of staminate and carpellate flowers of Schisandra chinensis (Schisandraceae) was investigated with scanning electron microscopy, with observations on the development of tepals reported for the first time. The results showed that there is no interval between the initiation of the last tepal and that of the first stamen or carpel, and that the shapes of tepal, stamen, and carpel primordia are similar. The tepals and stamens of staminate flowers are initiated acropetally in a continuous spiral Fibonacci phyllotaxis, with no carpel structures observed; the filaments are not connate. The organogenesis of the carpellate flowers is similar to that of the staminate flowers, but with no evidence of stamen development. The carpels are ascidiate without postgenital fusion. Three androecial characters of Schisandra and Kadsura are discussed in a phylogenetic context. The subglobose or obovoid androecium of Schisandra propinqua and Schisandra plena may be homologous with that in sections Kadsura and Sarcocarpon. The plesiomorphic form of the androecium within the two genera is likely to be elongate with more than ten free stamens.     

New combinations and typifications in <Emphasis Type="Italic">Bistorta</Emphasis>, <Emphasis Type="Italic">Persicaria</Emphasis>, <Emphasis Type="Italic">Polygonum,</Emphasis> and <Emphasis Type="Italic">Rumex</Emphasis> (Polygonaceae)

New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.     

The tyrosine <Emphasis Type="Italic">O</Emphasis>-prenyltransferase SirD catalyzes <Emphasis Type="Italic">O</Emphasis>-, <Emphasis Type="Italic">N</Emphasis>-, and <Emphasis Type="Italic">C</Emphasis>-prenylations

Recently, the prenyltransferase SirD was found to be responsible for the O-prenylation of tyrosine in the biosynthesis of sirodesmin PL in Leptosphaeria maculans. In this study, the behavior of SirD towards phenylalanine/tyrosine and tryptophan derivatives was investigated. Product formation has been observed with 12 of 19 phenylalanine/tyrosine derivatives. It was shown that the alanine structure attached to the benzene ring and an electron donor, e.g., OH or NH₂, at its para-position are essential for the enzyme activity. Modifications were possible both at the side chain and the benzene ring. Enzyme products from seven phenylalanine/tyrosine derivatives were isolated and characterized by MS and NMR analyses including HSQC and HMBC and proven to be O- or N-prenylated derivatives at position C4 of the benzene rings. K _M values of six selected derivatives were found in the range of 0.10–0.68 mM. Catalytic efficiencies (K _cat/K _M ) were determined in the range of 430–1,110 s⁻¹·M⁻¹ with l-tyrosine as the best substrate. In addition, 7 of 14 tested tryptophan analogs were also accepted by SirD and converted to C7-prenylated derivatives, which was confirmed by comparison with products obtained from enzyme assays using a 7-dimethylallyltryptophan synthase 7-DMATS from Aspergillus fumigatus.     

Screening of taxol-producing endophytic fungi from <Emphasis Type="Italic">Taxus chinensis</Emphasis> var. <Emphasis Type="Italic">mairei</Emphasis>

A total of 38 endophytic fungus strains were isolated from Taxus chinensis var. mairei by the aseptic technique. Genomic DNA was extracted from isolated endophytic fungi and subjected to polymerase chain reaction (PCR) analysis for the presence of the Taxus taxadiene synthase (TS) gene, a rate-limiting enzyme gene in the taxol biosynthetic pathway. Twelve out of 38 isolated endophytic fungus strains showed PCR positive for the ts gene. Subsequently, taxol and its related compounds were extracted from culture filtrates and mycelia of the PCR positive strains, separated by column chromatography, and analyzed by High Performance Liquid Chromatography and Mass Spectrum. The analysis result showed that 3 strains could produce taxol and its related compounds at the detectible level. This study indicates that molecular detection of the ts gene is an efficient method for primary screening of taxol or its related compound-producing endophytic fungi, which can improve prominently screening efficiency. Published in Russian in Prikladnaya Biokhimiya i Mikrobiologiya, 2007, Vol. 43, No. 4, pp. 490–494. The text was submitted by the authors in English.     

The <Emphasis Type="Italic">Caenorhabditis</Emphasis><Emphasis Type="Italic">briggsae</Emphasis> genome contains active <Emphasis Type="Italic">CbmaT1</Emphasis> and <Emphasis Type="Italic">Tcb1</Emphasis> transposons

The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.     

The Mating System of <Emphasis Type="Italic">Amegilla</Emphasis> (<Emphasis Type="Italic">Asarapoda</Emphasis>) <Emphasis Type="Italic">paracalva</Emphasis> Brooks (Hymenoptera: Apidae)

Males of the solitary bee Amegilla (Asarapoda) paracalva employ two mate-locating tactics: aggressive defense of sites from which virgin females are emerging and patrolling flower patches that are visited by conspecific females. At one study site, a single male was able to control an entire emergence area for one or more days. Multiple males patrolled one flower patch, interacting aggressively on occasion but no one individual was able to monopolize this resource. Territorial males at the emergence site secured mates by waiting by tunnels for receptive virgin females to emerge after metamorphosis. Males patrolling the flower patch pounced upon flower visiting conspecifics and mated with receptive females there. Territorial males at the emergence site were larger than average individuals, probably because of the advantage larger males have when grappling with opponents. Flower patrolling males were smaller than territorial males at the emergence sites, perhaps because of the advantages gained by these males from rapid, agile flight.     

Actinomycetemcomitin: a new bacteriocin produced by <Emphasis Type="Italic">Aggregatibacter</Emphasis> (<Emphasis Type="Italic">Actinobacillus</Emphasis>) <Emphasis Type="Italic">actinomycetemcomitans</Emphasis>

Aggregatibacter (Actinobacillus) actinomycetemcomitans P_7–20 strain isolated from a periodontally diseased patient has produced a bacteriocin (named as actinomycetemcomitin) that is active against Peptostreptococcus anaerobius ATCC 27337. Actinomycetemcomitin was produced during exponential and stationary growth phases, and its amount decreased until it disappeared during the decline growth phase. It was purified by ammonium sulphate precipitation (30–60% saturation), and further by FPLC (mono-Q ionic exchange and Phenyl Superose hydrophobic interaction) and HPLC (C-18 reversed-phase). This bacteriocin loses its activity after incubation at a pH below 7.0 or above 8.0, following heating for 30 min at 45°C, and after treatment with proteolytic enzymes such as trypsin, α-chymotrypsin, and papain. Actinomycetemcomitin has a molecular mass of 20.3 KDa and it represents a new bacteriocin from A. actinomycetemcomitans.     

<Emphasis Type="Italic">Funastrum rupicola</Emphasis> (<Emphasis Type="Italic">Apocynaceae:</Emphasis><Emphasis Type="Italic">Asclepiadoideae</Emphasis>), a new species from Bolivia

Summary   Funastrum rupicola Goyder, a new species of Apocynaceae: Asclepiadoideae from Bolivia, is described and illustrated. The conservation status of this species is assessed.     

Plant and supplementary food sources effect the development of <Emphasis Type="Italic">Dicyphus errans</Emphasis> (Hemiptera: Miridae)

Dicyphus errans (Wolff) (Hemiptera: Miridae) is an omnivorous predator of several pests attacking tomato and other vegetable crops. The nymphal development of D. errans was studied in the presence of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs with or without a water source and in the presence of a leaf of cucumber, eggplant or tomato supplemented with variable food types (E. kuehniella eggs, Artemia sp. cysts, pollen or milk powder) or without the provision of any food. Water provision was found to be essential for the completion of nymphal development even when animal food was offered to predators. When nymphs foraged on leaves in the absence of any food type, development was significantly more favoured on eggplant and cucumber than on tomato. E. kuehniella eggs and Artemia sp. cysts enhanced development of D. errans in comparison to milk powder and pollen. Development and female weight were improved when the food types were offered to the nymphs on a plant leaf than when were provided together with only water. This study contributes to understanding the importance of water vs. plant feeding for the development of D. errans and reveals implications for its mass rearing and application in biological control.     

Prevalence,intensity and associated factor analysis of <Emphasis Type="Italic">Tropilaelaps</Emphasis><Emphasis Type="Italic">mercedesae</Emphasis> infesting <Emphasis Type="Italic">Apis</Emphasis><Emphasis Type="Italic">mellifera</Emphasis> in China

Tropilaelaps mercedesae is a serious ectoparasite of Apis mellifera in China. The aim of this study was to investigate the infestation rates and intensity of T. mercedesae in A. mellifera in China, and to explore the relative importance of climate, district, management practices and beekeeper characteristics that are assumed to be associated with the intensity of T. mercedesae. Of the 410 participating apiaries, 379 apiaries were included in analyses of seasonal infestation rates and 352 apiaries were included in multivariable regression analysis. The highest infestation rate (86.3%) of T. mercedesae was encountered in autumn, followed by summer (66.5%), spring (17.2%) and winter (14.8%). In autumn, 28.9% (93) of the infested apiaries were in the north (including the northeast and northwest of China), 71.1% (229) were in the central and south (including east, southeast and southwest China), and 306 apiaries (82.9%) were co-infested by both T. mercedesae and Varroa. Multivariable regression analysis showed that geographical location, season, royal jelly collection and Varroa infestation were the factors that influence the intensity of T. mercedesae. The influence of beekeeper’s education, time of beekeeping, operation size, and hive migration on the intensity of T. mercedesa was not statistically significant. This study provided information about the establishment of the linkage of the environment and the parasite and could lead to better timing and methods of control.     

Host Plant Perception and Selection in the Sibling Species <Emphasis Type="Italic">Macrolophus melanotoma</Emphasis> and <Emphasis Type="Italic">Macrolophus pygmaeus</Emphasis> (Hemiptera: Miridae)

The electroantennogram responses (EAGs) of Macrolophus melanotoma and Macrolophus pygmaeus (Hemiptera: Miridae) exposed to volatile compounds (VOCs) of host and non-host plants were compared. The VOCs were identified by gas chromatography. Hosts and non-hosts eliciting similar EAGs were tested in olfactory assays against plants without a significant EAGs for the two Macrolophus species. No characteristic VOC profile was found for hosts and non-hosts. Terpenes predominated in many hosts and carboxylic acids in non-hosts, but no specific VOCs were characteristic of host plants. Significant EAGs (maximum deflection values in mV) were recorded in plants with very different VOC profiles, both hosts and non-hosts. The EAGs were higher for M. melanotoma than for M. pygmaeus, and were higher for males than for females. In M. melanotoma the EAGs were greater with hosts than with non-hosts, but they were similar in M. pygmaeus. The EAGs were correlated with the concentrations of sesquiterpenes and alcohols in both species. In olfactory assays, M. melanotoma and M. pygmaeus preferred their respective hosts, but they did not discriminate between non-host with and without significant EAGs. According to the results, Macrolophus species are expected to rely on ubiquitous VOCs for the identification of their hosts. The variation in the EAGs between M. melanotoma and M. pygmaeus is attributed to the variation in the proportions of olfactory receptor neurones with different sensitivity to VOCs (e.g. sesquiterpenes). Host plant selection is discussed in the light of the perception of VOCs and the processing of information by the central nervous system.     

Genetic variation of wild litchi (<Emphasis Type="Italic">Litchi chinensis</Emphasis> Sonn. subsp. <Emphasis Type="Italic">chinensis</Emphasis>) revealed by microsatellites

Understanding the amount and distribution of genetic diversity in natural populations can inform the conservation strategy for the species in question. In this study, genetic variation at eight nuclear microsatellite loci was used to investigate genetic diversity and population structure of wild litchi (Litchi chinensis Sonn. subsp. chinensis). Totally 215 individuals were sampled, representing nine populations of wild litchi. All eight loci were polymorphic, with a total of 51 alleles. The expected heterozygosity in the nine populations ranged from 0.367 to 0.638 with an average value of 0.526. Inbreeding within wild litchi populations was indicated by a strong heterozygote defect. Significant bottleneck events were detected in the populations from Yunnan and Vietnam, which could be responsible for lower levels of genetic diversity in these populations. Measures of genetic differentiation (F _ST = 0.269) indicated strong differentiation among wild litchi populations. Significant correlation was found between genetic differentiation and geographical distance (r = 0.655, P = 0.002), indicating a strong isolation by distance in these populations. Bayesian clustering suggested genetic separation among three regional groups, namely, the western group, the central group and the eastern group. Some conservation strategies for wild litchi populations were also proposed based on our results.     

Multiple paternity in <Emphasis Type="Italic">Rhipicephalus</Emphasis> (<Emphasis Type="Italic">Boophilus</Emphasis>) <Emphasis Type="Italic">microplus</Emphasis> confirmed by microsatellite analysis

The aim of this study was to determine if individual ticks among the progeny of a single female Rhipicephalus (Boophilus) microplus tick removed from cattle under natural conditions are the result of mating with one or several males. To this end, simulations were run using an existing dataset of genotypes from 8 microsatellite loci to predict the number of samples required and the best locus. Subsequently, 14–22 progeny from each of 15 engorged female ticks removed from three cows, and the engorged females themselves, were genotyped for the BmM1 locus and the minimum number of potential male parents was determined for each progeny group. Of the 15 progeny groups, 10 must have been sired by more than one male, as indicated by the presence of five unique alleles among the progeny or three unique alleles that could not have been contributed by the female. This finding demonstrates multiple paternity in R. microplus.     

First record of the tick <Emphasis Type="Italic">Ixodes</Emphasis> (<Emphasis Type="Italic">Pholeoixodes</Emphasis>) <Emphasis Type="Italic">kaiseri</Emphasis> in Turkey

Nymphs and larvae belonging to Ixodes spp. were collected from a red fox in Turkey. The ticks were identified morphologically and molecularly (16S rDNA PCR and phylogenetic analysis) as I. kaiseri. Sequence and phylogenetic analyses show that our I. kaiseri isolate is very similar to I. kaiseri isolates collected from Germany, Serbia, Romania, and Hungary. Therefore, the existence of I. kaiseri has been demonstrated for the first time in Turkey. More studies relating to the regional distribution and vectorial competence of I. kaiseri are needed.     

Evaluation of the toxicity of <Emphasis Type="Italic">Arthrospira</Emphasis> (<Emphasis Type="Italic">Spirulina</Emphasis>) <Emphasis Type="Italic">platensis</Emphasis> extract

In this study, the methanol extract of Arthrospira (Spirulina) platensis was examined for acute and subchronic toxicities. The extract did not produce any sign of toxicity within 7 days after feeding it at a single high dose of 6 g kg⁻¹ body weight to female and male Swiss mice. For the subchronic toxicity test, the extract at doses of 6, 12, and 24 mg kg⁻¹ body weight was orally administered to six male and six female Wistar rats daily for 12 weeks. Throughout the study period, we did not observe any abnormalities on behavior, food and water intakes, and health status among the treated animals. The hematology and clinical chemistry parameters of treated groups did not significantly differ from those of the controls in both sexes. Postmortem examination of the test groups also showed no abnormalities in both gross and histological findings. These results thus suggest that the methanol extract of A. platensis did not cause acute or subchronic toxicity in our experimental animals.     

A noteworthy record of <Emphasis Type="Italic">Ornithodoros</Emphasis> (<Emphasis Type="Italic">Alectorobius</Emphasis>) <Emphasis Type="Italic">coniceps</Emphasis> (Ixodida: Argasidae) from Central Italy

The first record of Ornithodoros (Alectorobius) coniceps (Canestrini) was reported for Italy in 1877, inside the interstices of the ancient mosaics at S. Marco Basilica in Venice. Afterwards only few discoveries of the species are reported for Italy; the last record is dated back to 1984, in L’Aquila town (Abruzzo Region). The present study shows the data of a survey carried out as a result of a massive infestation by O. coniceps in an ancient villa in Anzio town (Latium region) recently restored. In the past decades the villa has been fallen into disrepair, becoming an occasional shelter for wild animals mainly pigeons, that colonized the whole building for generations. This case appears worthy of note because it is the first record of this species after more than 25 years in Italy. A total of 136 specimens were collected by three methods: manual, mechanical aspirators and Wilson traps. Wilson trapping indicates positive O. coniceps tropism for CO₂.