Sociality in <Emphasis Type="Italic">Euglossa</Emphasis> (<Emphasis Type="Italic">Euglossa</Emphasis>) <Emphasis Type="Italic">viridissima</Emphasis> Friese (Hymenoptera,Apidae, Euglossini)

Euglossa viridissima is an orchid bee that forms both solitary and multiple female nests, making it a suitable species for the study of factors leading to diverse degrees of sociality in Euglossines. We conducted observations in eight reused nests (where a first generation of bees had been produced) kept in artificial boxes from the Yucatan Peninsula, Mexico. Five nests were reused (reactivated) by a single female (SFN), two nests reused by a mother and one daughter (MFN1) and one nest reused by the mother and two daughters (MFN2). No single nest was reactivated by unrelated females. The number of foraging trips, their duration and the duration of cell provisioning was not different between SFN and MFN. The overall production of cells per female was not different either between both types of nest. However, in MFN although all females did lay eggs, there was a reproductive skew in favor of the mother (95 and 45% of the brood produced in MFN1 and MFN2 respectively). She showed reproductive control of her daughters through oophagy and displaying threatening behavior when the daughters tried to open a cell where she had laid an egg. Brood losses to parasites (Anthrax sp. (Bom-byliidae) and Hoplostelis bivittata (Megachilidae)) were only found in SFN which possibly reflects and advantage of MFN in this respect. Our results coupled with other studies in Euglossa, reveal that a wide range of social behaviors occur in this genus, from solitary and communal to primitive reproductive division of labor. Multiple factors involving different levels of pressure imposed by food availability and parasites may favor such a diverse range of nesting behaviors. Interestingly, female associations in E. viridissima seem a result of kin selection that is enforced by coercion from mother females on their daughters. More studies are needed to shed light upon the social organization of Euglossa and other Euglossines and on their phylogenetic relationships in order to trace the origins of eusociality in Apidae. Received 12 February 2008; revised 25 June 2008; accepted 17 July 2008.     

Mating System and Sleeping Behaviour of the Male and Female <Emphasis Type="Italic">Centris</Emphasis> (<Emphasis Type="Italic">Paracentris</Emphasis>) <Emphasis Type="Italic">burgdorfi</Emphasis> Friese (Apidae,Centridini)

We describe the mating behaviour of males of Centris (Paracentris) burgdorfi, a solitary, univoltine bee, with a wide distribution in Brazil. We also describe the unusual sleeping sites of males and females. The study was performed during two breeding seasons, in northeastern Brazil, where the species nests in aggregations in petrified dunes. Data on mating behaviour were collected through direct observations of the bees at the nesting-emergence site. Males compete intensely for virgin females in the morning, sometimes killing rivals. The high competition for females near the nesting site makes that the male has to take the female to another place to get genital contact. In the evening, males do not use plants to spend the night, instead they aggregate in sleeping clusters inside old burrows in the nesting-emergence area while females sleep in groups on plants that provide the floral oil used in nest construction.     

The Mating System of <Emphasis Type="Italic">Habropoda pallida</Emphasis> Timberlake (Anthophorinae: Apidae)

Males of Habropoda pallida searched for recently emerged females at a location in central Arizona where many females had nested in the preceding year. Patrolling males exhibited a variety of mate locating tactics ranging from inspecting existing emergence holes to patrolling flights around flowering creosote bush. These tactics appear to be under the control of a conditional strategy, given that male behavior shifted during the day. Moreover, some marked males mounted dead females placed on the ground in the emergence area as well as mounting dead females pinned to flowers in the emergence area and at a creosote bush some distance away. At least some males exhibited site fidelity in that numerous males marked within the nest site emergence area were recaptured there; others marked at a creosote bush were also seen again at that plant. The mating system of the bee involves scramble competition with individual males attempting to locate receptive emerging and flower-visiting females before rival males. In keeping with the scramble competition hypothesis, males are considerably smaller on average than females and are only aggressive when trying to push their way past rival males already mounted on a potential mate.     

<Emphasis Type="Italic">STAYGREEN</Emphasis> (<Emphasis Type="Italic">CsSGR</Emphasis>) is a candidate for the anthracnose (<Emphasis Type="Italic">Colletotrichum orbiculare</Emphasis>) resistance locus <Emphasis Type="Italic">cla</Emphasis> in Gy14 cucumber

Key message

Map-based cloning identified a candidate gene for resistance to the anthracnose fungal pathogen Colletotrichum orbiculare in cucumber, which reveals a novel function for the highly conserved STAYGREEN family genes for host disease resistance in plants.

Abstract

Colletotrichum orbiculare is a hemibiotrophic fungal pathogen that causes anthracnose disease in cucumber and other cucurbit crops. No host resistance genes against the anthracnose pathogens have been cloned in crop plants. Here, we reported fine mapping and cloning of a resistance gene to the race 1 anthracnose pathogen in cucumber inbred lines Gy14 and WI 2757. Phenotypic and QTL analysis in multiple populations revealed that a single recessive gene, cla, was underlying anthracnose resistance in both lines, but WI2757 carried an additional minor-effect QTL. Fine mapping using 150 Gy14?×?9930 recombinant inbred lines and 1043 F₂ individuals delimited the cla locus into a 32 kb region in cucumber Chromosome 5 with three predicted genes. Multiple lines of evidence suggested that the cucumber STAYGREEN (CsSGR) gene is a candidate for the anthracnose resistance locus. A single nucleotide mutation in the third exon of CsSGR resulted in the substitution of Glutamine in 9930 to Arginine in Gy14 in CsSGR protein which seems responsible for the differential anthracnose inoculation responses between Gy14 and 9930. Quantitative real-time PCR analysis indicated that CsSGR was significantly upregulated upon anthracnose pathogen inoculation in the susceptible 9930, while its expression was much lower in the resistant Gy14. Investigation of allelic diversities in natural cucumber populations revealed that the resistance allele in almost all improved cultivars or breeding lines of the U.S. origin was derived from PI 197087. This work reveals an unknown function for the highly conserved STAYGREEN (SGR) family genes for host disease resistance in plants.

     

<Emphasis Type="Italic">In silico</Emphasis> and <Emphasis Type="Italic">in situ</Emphasis> characterization of the zebrafish (<Emphasis Type="Italic">Danio rerio</Emphasis>) <Emphasis Type="Italic">gnrh3</Emphasis> (sGnRH) gene

Background

Gonadotropin releasing hormone (GnRH) is responsible for stimulation of gonadotropic hormone (GtH) in the hypothalamus-pituitary-gonadal axis (HPG). The regulatory mechanisms responsible for brain specificity make the promoter attractive for in silico analysis and reporter gene studies in zebrafish (Danio rerio).

Results

We have characterized a zebrafish [Trp⁷, Leu⁸] or salmon (s) GnRH variant, gnrh 3. The gene includes a 1.6 Kb upstream regulatory region and displays the conserved structure of 4 exons and 3 introns, as seen in other species. An in silico defined enhancer at -976 in the zebrafish promoter, containing adjacent binding sites for Oct-1, CREB and Sp1, was predicted in 2 mammalian and 5 teleost GnRH promoters. Reporter gene studies confirmed the importance of this enhancer for cell specific expression in zebrafish. Interestingly the promoter of human GnRH-I, known as mammalian GnRH (mGnRH), was shown capable of driving cell specific reporter gene expression in transgenic zebrafish.

Conclusions

The characterized zebrafish Gnrh3 decapeptide exhibits complete homology to the Atlantic salmon (Salmo salar) GnRH-III variant. In silico analysis of mammalian and teleost GnRH promoters revealed a conserved enhancer possessing binding sites for Oct-1, CREB and Sp1. Transgenic and transient reporter gene expression in zebrafish larvae, confirmed the importance of the in silico defined zebrafish enhancer at -976. The capability of the human GnRH-I promoter of directing cell specific reporter gene expression in zebrafish supports orthology between GnRH-I and GnRH-III.

     

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.     

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.     

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.     

Taxonomical notes on <Emphasis Type="Italic">Torymidae</Emphasis> (<Emphasis Type="Italic">Insecta: Hymenoptera: Chalcidoidea</Emphasis>)

As a result of investigations over type material from a collection of the Hungarian Natural History Museum, Budapest, a new synonym and two new combinations in the Torymidae family (Hymenoptera: Chalcidoidea) are proposed: Eridontomerus illiesi Szelényi, 1981 as a junior synonym of Cryptopristus caliginosus (Walker, 1833); Eridontomerus unidentatus Szelényi, 1973 is transferred to the genus Pseudotorymus Masi, 1921; and Idiomacromerus obscuripennis (Szelényi, 1973) is transferred to the genus Torymoides Walker, 1871.     

Bio-resolution of glycidyl (<Emphasis Type="Italic">o</Emphasis>, <Emphasis Type="Italic">m</Emphasis>, <Emphasis Type="Italic">p</Emphasis>)-methylphenyl ethers by <Emphasis Type="Italic">Bacillus megaterium</Emphasis>

A newly isolated Bacillus megaterium with epoxide hydrolase activity resolved racemic glycidyl (o, m, p)-methylphenyl ethers to give enantiopure epoxides in 84–99% enantiomeric excess and with 21–73 enantiomeric ratios. The (S)-enantiomer was obtained from rac-glycidyl (o or m)-methylphenyl ether while the (R)-epoxides was obtained from glycidyl p-methylphenyl ether. The observations are explained at the level by enzyme-substrate docking studies.     

Distribution and Conservation Status of the Lao Leaf Monkey (<Emphasis Type="Italic">Trachypithecus</Emphasis> (<Emphasis Type="Italic">francoisi</Emphasis>) <Emphasis Type="Italic">laotum</Emphasis>)

Lao leaf monkeys (Trachypithecus (francoisi) laotum) are endemic to a small area of central and, marginally, north Lao. They are known from a few, mostly vague, historical records. We here present a detailed examination of the distribution of this little-known taxon and discuss its conservation status. Surveys since 1992 show its range to be centered upon the karst-dominated Phou Hin Poun National Protected Area (NPA), Nam Sanam Provincial Protected Area, and the southern part of Nam Kading NPA. The known range encompasses <2000 km2, within which occurrence is patchy, reflecting habitat availability. The taxonomic identity of leaf monkeys plausibly of this group reported to the north of this area is not known. In the south of Phou Hin Poun NPA, village reports that the monkeys have black heads are corroborated by the few sightings; their taxonomic relationship with typical Trachypithecus laotum is unknown. In the mid–late 1990s large populations remained and individuals were easily seen. There is no apparent large-scale threat to their habitat. There has been no significant reassessment of status since the late 1990s, nor is there any active conservation action in place. Although the monkeys are to a significant extent protected by the arduous terrain, this cannot be relied upon indefinitely: Trade-directed hunting, although apparently limited in the 1990s, is a potential threat that could cause rapid population declines. Local traditions offer significant starting points for conserving these monkeys.     

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.     

<Emphasis Type="Italic">Sex combs reduced</Emphasis> (<Emphasis Type="Italic">Scr</Emphasis>) regulatory region of <Emphasis Type="Italic">Drosophila</Emphasis> revisited

The Hox gene Sex combs reduced (Scr) is responsible for the differentiation of the labial and prothoracic segments in Drosophila. Scr is expressed in several specific tissues throughout embryonic development, following a complex path that must be coordinated by an equally complex regulatory region. Although some cis-regulatory modules (CRMs) have been identified in the Scr regulatory region (~75 kb), there has been no detailed and systematic study of the distinct regulatory elements present within this region. In this study, the Scr regulatory region was revisited with the aim of filling this gap. We focused on the identification of Initiator elements (IEs) that bind segmentation factors, Polycomb response elements (PREs) that are recognized by the Polycomb and Trithorax complexes, as well as insulators and tethering elements. To this end, we summarized all currently available information, mainly obtained from high throughput ChIP data projects. In addition, a bioinformatic analysis based on the evolutionary conservation of regulatory sequences using the software MOTEVO was performed to identify IE and PRE candidates in the Scr region. The results obtained by this combined strategy are largely consistent with the CRMs previously identified in the Scr region and help to: (i) delimit them more accurately, (ii) subdivide two of them into different independent elements, (iii) identify a new CRM, (iv) identify the composition of their binding sites and (v) better define some of their characteristics. These positive results indicate that an approach that integrates functional and bioinformatic data might be useful to characterize other regulatory regions.     

Biology of <Emphasis Type="Italic">Lasioglossum</Emphasis> (<Emphasis Type="Italic">L.</Emphasis>) <Emphasis Type="Italic">majus</Emphasis> (Hymenoptera: Halictidae), a largely solitary sweat bee with behavioural adaptations to communality

Within the bee family Halictidae there have been three origins of sociality. Although detection of origins and reversal from sociality requires phylogenetic studies, at a behavioural level a predisposition to sociality can be detected by analysis of intra-specific interactions. We studied aspects of nesting biology and behavioural interactions in Lasioglossum (Lasioglossum) majus, a poorly known halictine inhabiting temperate regions of Europe, which is suspected to be solitary. Nests were found to be largely used by one female, but some were shared by more than one individual. These few nests, whose entrances were very close to each other, were found to be connected underground. A few individuals were observed to enter in a nest where a female was waiting, behaving as a guard and allowing the incoming bee to enter the nest. By use of circle-tube experiments, the behavioural repertoire exhibited by females during encounters was assessed. Levels of withdrawal and cooperative events were comparable with those observed in other solitary nesting species, but aggressive events were very rare, as in several observed communal species. We conclude that L. (L.) majus females, despite general solitary nesting, possess behavioural components enabling them to adopt, probably in high nest-density areas, nest-sharing strategies. A similar kind of local social polymorphism has been observed in two other species of the subgenus Lasioglossum, but these are the first data available on a European species and the first record of subterranean connections among nests of halictid bees.     

<Emphasis Type="Italic">Rhipicephalus</Emphasis> (<Emphasis Type="Italic">Boophilus</Emphasis>) <Emphasis Type="Italic">microplus</Emphasis>: a most successful invasive tick species in West-Africa

The cattle tick Rhipicephalus (Boophilus) microplus is known to be a highly reproductive and efficient vector of Babesia bovis, two characters which make this tick a threat to livestock keeping in many continents. The authors identified this tick in Ivory Coast, West Africa, in 2007, and hypothesized the spread to be minimal, as this tick was not observed in previous years. To determine the extent of its distribution and to a lesser extent the possible impact of the tick on the livelihoods of Ivorian smallholders, a cross-sectional survey was carried out in the Abidjan and Agboville Departments of Ivory Coast, in April 2008. The results of the study reveal that the newly introduced tick has almost completely displaced all indigenous Rhipicephalus (Boophilus) species in the study area and gave rise to unsuccessful tick control, inappropriate pesticide use, loss of milk production and even increased mortality in dairy cattle.     

The zebra mussel (<Emphasis Type="Italic">Dreissena polymorpha</Emphasis>) impacts European bitterling (<Emphasis Type="Italic">Rhodeus amarus</Emphasis>) load in a host freshwater mussel (<Emphasis Type="Italic">Unio pictorum</Emphasis>)

The European bitterling, Rhodeus amarus, is a non-indigenous fish species in British fresh waters. It lays its eggs in unionid mussels which themselves are vulnerable to fouling by the non-indigenous zebra mussel, Dreissena polymorpha. Observations from an unmanipulated natural system showed that only 27% of zebra mussel-fouled Unio pictorum hosted bitterling, while 47% of unfouled U. pictorum hosted bitterling. We conducted a field experiment in the River Great Ouse catchment, Cambridgeshire, England in May–June 2007 and 2008 to quantify the impact of zebra mussels on bitterling load in host mussels. Zebra mussel-fouled unionids were significantly less likely to host bitterling than unfouled unionids. The number of unionids hosting bitterling did not differ significantly whether the zebra mussels fouling the unionid were alive or dead. Bitterling appeared to discriminate against zebra mussel-fouled unionids less as the 2007 breeding season advanced, potentially because preferred unfouled unionids had a higher bitterling load, and were therefore relatively lower quality hosts than at the start of the breeding season.     

Spatio-temporal variation of colony structure and eusociality level of the Japanese sweat bee<Emphasis Type="Italic"> Lasioglossum</Emphasis> (<Emphasis Type="Italic">Evylaeus</Emphasis>)<Emphasis Type="Italic"> duplex</Emphasis> (Hymenoptera: Halictidae)

Colony structure and eusociality level of the sweat bee Lasioglossum (Evylaeus) duplex were studied in 2001 in Sapporo and Assabu, Hokkaido, northern Japan. Sakagami and his colleagues had also studied this species in Sapporo in 1957–1968. Brood size, sex ratio and queen–worker size dimorphism were geographically and temporally variable, indicating spatio-temporal variation at the eusociality level. Inseminated workers constituted only 7.9% of the populations in 1957–1968 Sapporo but about 60% in 2001 in Sapporo and Assabu. A few of the inseminated workers were believed to leave natal nests for independent colony founding. Thus, partial bivoltinism is likely in this sweat bee species. The presence of workers with developed ovaries and/or corpora lutea suggests the occurrence of worker oviposition.     

<Emphasis Type="Italic">Arthroderma benhamiae</Emphasis> (The Teleomorph of <Emphasis Type="Italic">Trichophyton mentagrophytes</Emphasis>) Mating Type-Specific Genes

This study first report to identify the mating type (−)-specific gene of alpha-box and the mating type (+)-specific gene of the high-mobility-group (HMG) DNA-binding domain in zoophilic dermatophytes of Arthroderma benhamiae in an effort to understand the epidemiological characteristics of Trichophyton mentagrophytes. The sequence of the alpha-box gene (1,387 bp) was found to contain two exons, from 184 to 475 bp and from 525 to 1,387 bp, coding a protein of 384 amino acids, beginning with a putative initiating methionine (ATG). The sequence of the HMG gene (1,910 bp) contained two exons, from 234 to 415 bp and from 479 to 1,457 bp, coding a protein of 386 amino acids, beginning with a putative initiating methionine (ATG).     

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.