Inheritance of white spots on the shell of Littorina obtusata (Gastropoda, Prosobranchia)

The hypothesis on monogenic inheritance of white spot pattern on the shell of the gastropod snail Littorina obtusata was tested. Although in most cases our results did not contradict this assumption, the hypothesis cannot explain the observed segregation in general. An alternative hypothesis was suggested, according to which the presence of spot pattern is controlled by two complementary biallelic genes.     

Inheritance of longitudinal shell bands in the snails <Emphasis Type="Italic">Littorina obtusata</Emphasis> and <Emphasis Type="Italic">L. saxatilis</Emphasis> (Gastropoda,Prosobranchia)

The hypothesis of a monogenic inheritance of dark longitudinal bands on the shell in the gastropods Littorina obtusata and L. saxatilis was checked. One gene having two alleles proved to be responsible for the shell banding pattern in both of the species. The presence of bands was a dominant character in either case.     

Drosophila suzukii wing spot size is robust to developmental temperature

Phenotypic plasticity is an important mechanism allowing adaptation to new environments and as such it has been suggested to facilitate biological invasions. Under this assumption, invasive populations are predicted to exhibit stronger plastic responses than native populations. Drosophila suzukii is an invasive species whose males harbor a spot on the wing tip. In this study, by manipulating developmental temperature, we compare the phenotypic plasticity of wing spot size of two invasive populations with that of a native population. We then compare the results with data obtained from wild‐caught flies from different natural populations. While both wing size and spot size are plastic to temperature, no difference in plasticity was detected between native and invasive populations, rejecting the hypothesis of a role of the wing‐spot plasticity in the invasion success. In contrast, we observed a remarkable stability in the spot‐to‐wing ratio across temperatures, as well as among geographic populations. This stability suggests either that the spot relative size is under stabilizing selection, or that its variation might be constrained by a tight developmental correlation between spot size and wing size. Our data show that this correlation was lost at high temperature, leading to an increased variation in the relative spot size, particularly marked in the two invasive populations. This suggests: (a) that D. suzukii's development is impaired by hot temperatures, in agreement with the cold‐adapted status of this species; (b) that the spot size can be decoupled from wing size, rejecting the hypothesis of an absolute constraint and suggesting that the wing color pattern might be under stabilizing (sexual) selection; and (c) that such sexual selection might be relaxed in the invasive populations. Finally, a subtle but consistent directional asymmetry in spot size was detected in favor of the right side in all populations and temperatures, possibly indicative of a lateralized sexual behavior.     

<i>Aspergillus tubingensis</i> Causes Leaf Spot of Cotton (<i>Gossypium hirsutum</i> L.) in Pakistan

Cotton (Gossypium hirsutum L.) is a key fiber crop of great commercial importance. Numerous phytopathogens decimate crop production by causing various diseases. During July-August 2018, leaf spot symptoms were recurrently observed on cotton leaves in Rahim Yar Khan, Pakistan and adjacent areas. Infected leaf samples were collected and plated on potato dextrose agar (PDA) media. Causal agent of cotton leaf spot was isolated, characterized and identified as Aspergillus tubingensis based on morphological and microscopic observations. Conclusive identification of pathogen was done on the comparative molecular analysis of CaM and β-tubulin gene sequences. BLAST analysis of both sequenced genes showed 99% similarity with A. tubingensis. Koch’s postulates were followed to confirm the pathogenicity of the isolated fungus. Healthy plants were inoculated with fungus and similar disease symptoms were observed. Fungus was re-isolated and identified to be identical to the inoculated fungus. To our knowledge, this is the first report describing the involvement of A. tubingensis in causing leaf spot disease of cotton in Pakistan and around the world.     

Geographical variation of elytral spot patterns in the phytophagous ladybird,Epilachna vigintioctopunctata (Coleoptera: Coccinellidae) in the Province of Sumatera Barat,Indonesia

Geographical variation in the elytral spot patterns of a phytophagous ladybird, Epilachna vigintioctopunctata, was studied in the Province of Sumatera Barat, Indonesia. Populations of E. vigintioctopunctata were divided into four major groups (I–IV) by the incidence of spot pattern variations. Group I, occurring in the coastal plains and inland lowlands, and Group IV, confined to the highlands, were the extremes of the spot pattern variations, the latter had many more non-persistent spots and confluences with larger body size and advanced melanism than the former. These two groups were connected with each other via the intermediate groups. A positive relationship was detected between the elevations of sample sites and the average number of non-persistent spots per elytron. Consequently, present results favor the view that the two previously recognized forms of E. vigintioctopunctata (formae A and B inKatakura et al., 1988) represent a complicated intraspecific variation rather than two distinct sibling species. Elytral spot pattern variations were not different between the sexes or between the beetles collected from different kinds of host plants.     

Formation and function of the “Xestoleberis‐spot” in Xestoleberis hanaii (Crustacea: Ostracoda)

The crescent sculpture of the so‐called “Xestoleberis‐spot” develops inside the calcified valve of the family Xestoleberididae. Electron microscopic observations on both, intermoult and postmoult stages of Xestoleberis species reveal that the “Xestoleberis‐spot” system consists of three elements; two calcified chambers, a vesicle of electron‐dense material and an uncalcified procuticle. The formation and function of the “Xestoleberis‐spot” system are discussed. In conclusion, the “Xestoleberis‐spot” system functions as the muscle attachment site for several antennal muscles, and provides the material for chitinous fibers in the exocuticle of outer lamella. The unique cuticular structures of the family Xestoleberididae are due to the “Xestoleberis‐spot” system.     

Proteome analysis of <Emphasis Type="Italic">Aspergillus ochraceus</Emphasis>

Genome sequencing for many important fungi has begun during recent years; however, there is still some deficiency in proteome profiling of aspergilli. To obtain a comprehensive overview of proteins and their expression, a proteomic approach based on 2D gel electrophoresis and MALDI-TOF/TOF mass spectrometry was used to investigate A. ochraceus. The cell walls of fungi are exceptionally resistant to destruction, therefore two lysis protocols were tested: (1) lysis via manual grinding using liquid nitrogen, and (2) mechanical lysis via rapid agitation with glass beads using MagNalyser. Mechanical grinding with mortar and pestle using liquid nitrogen was found to be a more efficient extraction method for our purpose, resulting in extracts with higher protein content and a clear band pattern in SDS-PAGE. Two-dimensional electrophoresis gave a complex spot pattern comprising proteins of a broad range of isoelectric points and molecular masses. The most abundant spots were subjected to mass spectrometric analysis. We could identify 31 spots representing 26 proteins, most of them involved in metabolic processes and response to stress. Seventeen spots were identified by de novo sequencing due to a lack of DNA and protein database sequences of A. ochraceus. The proteins identified in our study have been reported for the first time in A. ochraceus and this represents the first proteomic approach with identification of major proteins, when the fungus was grown under submerged culture.     

Identification of a major quantitative trait locus (QTL) for yellow spot (<Emphasis Type="Italic">Mycovellosiella koepkei</Emphasis>) disease resistance in sugarcane

In this study we used amplified fragment length polymorphism (AFLP) and microsatellite (short sequence repeat or SSR) markers to identify a major quantitative trail locus (QTL) for yellow spot (Mycovellosiella koepkei) disease resistance in sugarcane. A bi-parental cross between a resistant variety, M 134/75, and a susceptible parent, R 570, generated a segregating population of 227 individuals. These clones were evaluated for yellow spot infection in replicated field trials in two locations across two consecutive years. A χ²-test (χ² at 98% confidence level) of the observed segregation pattern for yellow spot infection indicated a putative monogenic dominant inheritance for the trait with a 3 (resistant):1(susceptible) ratio. The AFLP and SSR markers identified 666 polymorphisms as being present in the resistant parent and absent in the susceptible one. A genetic map of M 134/75 was constructed using 557 single-dose polymorphisms, resulting in 95 linkage groups containing at least two markers based on linkages in coupling. QTL analysis using QTLCartographer v1.17d and MAPMAKER/QTL v1.1 identified a single major QTL located on LG87, flanked by an AFLP marker, actctc10, and an SSR marker, CIR12284. This major QTL, which was found to be linked at 14 cM to an AFLP marker, was detected with LOD 8.7, had an additive effect of −10.05% and explained 23.8% of the phenotypic variation of yellow spot resistance.     

Quantitative analysis of safranal in saffron extract and nanoparticle formulation by a validated high‐performance thin‐layer chromatographic method†

Introduction – Safranal is an effective anticonvulsant shown to act as an agonist at GABA_A receptors. Nose to brain delivery via nanoparticle formulation might improve its brain delivery. A selective and sensitive analytical method is required for evaluation of safranal‐based novel drug delivery systems. Objective – To develop and validate a high‐performance thin‐layer chromatographic (HPTLC) method for the quantitative analysis of safranal as bulk, in saffron extract and in developed safranal‐loaded nanoparticle formulation. Methodology – Chromatographic separation was achieved on silica gel pre‐coated TLC aluminium plates 60F‐254, using n‐hexane:ethyl acetate (9 : 1, v/v) as the mobile phase. Quantitative analysis was carried out by densitometry at a wavelength of 310 nm. The method was validated and applied to detect related impurities, to analyse safranal in saffron extract and to evaluate safranal‐loaded nanoparticles. Results – Compact spots of safranal were observed at R_f value 0.51 ± 0.02. The method was linear (r = 0.9991) between 0.5 and 5.0 μg/spot. The intra‐ and inter‐day precisions were 1.08–2.17 and 1. 86–3.47%, respectively. The limit of detection was 50 ng/spot and the limit of quantification was 150 ng/spot. The method proved to be accurate (recovery 97.4–102.0%) and was selective for safranal. Evaluation of safranal‐loaded nanoparticle formulation demonstrated drug loading of 23.0%, encapsulation efficiency of 42.0% and sustained drug release following biphasic pattern. Conclusion – The present method is useful for the quantitative and qualitative analysis of safranal and safranal‐loaded nanoparticle formulation. It provides significant advantages in terms of greater specificity and rapid analysis. Copyright © 2009 John Wiley & Sons, Ltd.     

Spatial Distribution of Galls Caused by <Emphasis Type="Italic">Aculus tetanothrix</Emphasis> (Acari: Eriophyoidea) on Arctic Willows

The distribution of galls caused by Aculus tetanothrix (Acari: Eriophyoidea) on three Salix species was studied. The factors influencing this distribution were analysed, i.e. willow species, study area and shoot length. Spatial pattern of gall distribution within the shoot was also examined. The study was conducted in Russia, Kola Peninsula. Densities of galls caused by A. tetanothrix differed significantly among willow species. Considerably higher gall density was recorded in the White Sea coast than in the Khibiny Mountains. This may be explained by the influence of a milder maritime climate that favors mite occurrence compared to a harsh and variable mountain climate that limits mite abundance. There was no relationship between the gall density and the shoot length. The highest density of galls was recorded on the inner offshoots; within the offshoot, there was a maximum density on the fifth leaf. This pattern was repeatable for all shoots studied, independent of the study area, willow species and length of shoots, suggesting the optimal conditions for A. tetanothrix exist on leaves in the middle part of a shoot. This distribution pattern may be an effect of the trade-off between the costs and benefits resulting from leaf quality and mite movement along the shoot. This hypothesis, however, needs to be tested experimentally.     

On some ecological aspects of the lugworm <Emphasis Type="Italic">Abarenicola affinis chiliensis</Emphasis> Wells, 1963 (Polychaeta: Scolecida: Arenicolidae) from shallow soft bottoms of northern Chile

We conducted an ecological study of a population of the polychaete Abarenicola affinis chiliensis in the shallow subtidal zone of Caleta Guardiamarina Riquelme in northern Chile. The study area is characterized by a hypoxic bottom consisting of fine sands and a silt-clay mixture, with high values of total organic matter content (TOM > 20%). During the two study periods (spring 1996 and 1997), the numerical contribution of A. affinis chiliensis to the total macrofauna was greater than 80%. A similar pattern was recorded for biomass, with A. affinis chiliensis surpassing 95% of the total macrofauna biomass. Statistical analyses did not detect significant differences in environmental and biotic variables between years (with the exception of salinity, which increased slightly), indicating temporal stability of these variables over the study period. Our results do not support the hypothesis of Wells that seawater temperatures act as a physical barrier impeding the dispersal of Abarenicola species. This hypothesis should be reexamined for some representatives of Abarenicola on the Pacific coast of South America.     

Mosaic Evolution of the Basicranium in <Emphasis Type="Italic">Homo</Emphasis> and its Relation to Modular Development

Mosaic evolution describes different rates of evolutionary change in different body units. Morphologically these units are described by more relationships within a unit than between different units which relates mosaic evolution with morphological integration and modularity. Recent evidence suggests mosaic evolution at the human basicranium due to different evolutionary rates of midline and lateral cranial base morphology but this hypothesis has not yet been addressed explicitly. We this hypothesis and explore how mosaic evolution relates to modular development. Evolutionary data sets on midline (N = 186) and lateral (N = 86) basicranial morphology are compared with 3D data on pre- and postnatal basicranial ontogeny (N = 71). Our results support the hypothesis of mosaic evolution and suggest a modular nature of basicranial development. Different embryological basicranial units likely became differently modified during evolution, with relatively stable midline elements and more variable lateral elements. In addition, developmental data suggests that modularity patterns change throughout ontogeny. During prenatal ontogeny lateral basicranial elements (greater sphenoid wings and petrosal pyramids) change together compared with the midline base. Close to birth the greater sphenoid wings keep a spatially stable position, while the petrosal pyramids become dissociated and shifted posteriorly. After birth the greater sphenoid wings and petrosal pyramids change again jointly and with respect to midline cranial base elements. This sequential pattern of integration and modularization and re-integration describes human basicranial ontogeny in a way that is potentially important for the understanding of evolutionary change. Phylogenetic modifications of this pattern during morphogenesis, growth, and development may underlie the mosaic evolution of the hominin basicranium.     

Positional cloning of <Emphasis Type="Italic">ds1</Emphasis>, the target leaf spot resistance gene against <Emphasis Type="Italic">Bipolaris sorghicola</Emphasis> in sorghum

Target leaf spot is one of the major sorghum diseases in southern Japan and caused by a necrotrophic fungus, Bipolaris sorghicola. Sorghum resistance to target leaf spot is controlled by a single recessive gene (ds1). A high-density genetic map of the ds1 locus was constructed with simple sequence repeat markers using progeny from crosses between a sensitive variety, bmr-6, and a resistant one, SIL-05, which allowed the ds1 gene to be genetically located within a 26-kb region on the short arm of sorghum chromosome 5. The sorghum genome annotation database for BTx623, for which the whole genome sequence was recently published, indicated a candidate gene from the Leucine-Rich Repeat Receptor Kinase family in this region. The candidate protein kinase gene was expressed in susceptible plants but was not expressed or was severely reduced in resistant plants. The expression patterns of ds1 gene and the phenotype of target leaf spot resistance were clearly correlated. Genomic sequences of this region in parental varieties showed a deletion in the promoter region of SIL-05 that could cause reduction of gene expression. We also found two ds1 alleles for resistant phenotypes with a stop codon in the coding region. The results shown here strongly suggest that the loss of function or suppression of the ds1 protein kinase gene leads to resistance to target leaf spot in sorghum.     

Role of cyclosis in asymmetric formation of alkaline zones at the boundaries of illuminated region in <Emphasis Type="Italic">Chara</Emphasis> cells

The role of cytoplasmic streaming in pattern formation at the plasma membrane and chloroplast layer was examined with Chara corallina Klein ex Willd. cells exposed to nonuniform illumination. Our hypothesis was that the exchange of ions and metabolites between the chloroplasts and the cytoplasm in the illuminated cell area alters the composition of the cytosol while the flow of modified cytoplasm induces asymmetrical changes in the plasmalemmal transport and fluorescence of chloroplasts in the adjacent shaded areas. The hypothesis was tested by measuring the H⁺-transporting activity of plasmalemma and non-photochemical quenching (NPQ) in shaded areas of Chara cells at distances of 1–5 mm on either side of the illuminated region (white light, 1000 μmol/(m² s), beam width 2 mm). When measured at equal distances on opposite sides from the illuminated region, both pH and NPQ changes differed considerably depending on the direction of cytoplasmic movement at the light-shade boundary. In the region where the cytoplasm flowed out of irradiated area, the formation of alkaline zone (the plasma membrane domain with a high H⁺-conductance) and NPQ in chloroplasts was observed. In the vicinity of light-shade boundary where the flow was directed from the shade to the illuminated area, neither alkaline zone nor NPQ were formed. The results demonstrate the significance of cyclosis in the transfer of physiologically active intermediate that affects the membrane transport, the functional activity of chloroplasts, and the pattern formation in the plant cell.     

Seasonal variability of wing length and eyespots in populations of <Emphasis Type="Italic">Erebia ligea</Emphasis> (L.) (Lepidoptera,Satyridae) in the Middle Urals

The flight period of Erebia ligea (Linnaeus, 1758) in the Sysert District of Sverdlovsk Province lasts from early July until early August only in the odd-numbered years. The species is characterized by protandry, its males emerging 5–7 days before females. Erebia ligea manifests sexual and seasonal variation of the wing length and diameter of the eyespots in the Middle Urals. According to the literature and newly obtained data, the relative male/female wing length varies within the species range. The vectors of the seasonal variation of the body size are opposite in the males and females: in early summer the largest males and the smallest females occur, then mediumsized individuals appear, while the smallest males and the largest females fly at the end of the warm period. Although the males of Erebia ligea are larger than females, the latter have larger eyespots on the wings. Seasonal variation of the diameters of the forewing eyespots is largely similar in the two sexes: individuals with larger spots appear earlier in the season than those with small spots. The eyespots treated as phenes in this study develop on the wings only if the remaining spots of the wing pattern attain a threshold size. A threshold nature was shown for P4 spot in M ₃-Cu ₁ cell of the fore wing and G2 spot in cell M ₁–M ₂ of the hind wing. Individuals with and without phene G2 have opposite vectors of seasonal variation of the sizes of the rest spots of the hind wing pattern. It is apparently the threshold character of variation of these elements of the wing pattern that defines the variation of the proportion of phenetic combinations of the eyespots in the individuals emerging in different periods of the season. Describing phenetic variation at the population level, one should remember that the percentage of the “morphs” or phenetic combinations may vary during a season, especially in the protandric species.     

Evaluation of Hydrangea macrophylla for Resistance to Leaf‐Spot Diseases

Garden hydrangea (Hydrangea macrophylla) is a popular ornamental plant that can be devastated by leaf‐spot diseases. Information is needed to determine susceptibility of commercial cultivars to leaf‐spot diseases. To address this need, 88 cultivars of H. macrophylla were evaluated for their resistance to leaf‐spot diseases in full‐shade (2007–2008), full‐sun (2007–2008) and partial‐shade (2009–2010) environments in McMinnville, TN, USA. Ten cultivars [‘Ami Pasquier’, ‘Ayesha’, ‘Blue Bird’, ‘Forever Pink’, ‘Fuji Waterfall’ (‘Fujinotaki’), ‘Miyama‐yae‐Murasaki’, ‘Seafoam’, ‘Taube’, ‘Tricolor’ and ‘Veitchii’] were rated resistant (R) or moderately resistant to leaf spot under each of the three environments. In 2007–2008, approximately 51% of the cultivars were rated R in full shade, but only 5% were R in full sun. In 2009–2010, only 1% of the cultivars were rated R in partial shade. Although environmental parameters including temperature and rainfall influence disease severity and host reaction, a shaded environment was least favourable for leaf‐spot disease development, which demonstrates that establishing hydrangea in shaded environment can be an effective tool along with cultivar selection for managing leaf‐spot diseases on hydrangea. Six pathogens, Corynespora cassiicola, Cercospora spp., Myrothecium roridum, Glomerella cingulata (Anamorph: Colletotrichum gloeosporioides), Phoma exigua and Botrytis cinerea, were associated with leaf‐spot diseases of garden hydrangea. Of the leaf‐spot pathogens, C. cassiicola was most frequently isolated (55% of all isolates), followed by Cercospora spp. (20%) and other pathogens (25%). Because symptoms attributed to each leaf‐spot pathogen were similar, cultivars were selected for resistance to multiple leaf‐spot pathogens.     

Floral integration,phenotypic covariance structure and pollinator variation in bumblebee‐pollinated Helleborus foetidus

By analysing patterns of phenotypic integration and multivariate covariance structure of five metric floral traits in nine Iberian populations of bumblebee‐pollinated Helleborus foetidus (Ranunculaceae), this paper attempts to test the general hypothesis that pollinators enhance floral integration and selectively modify phenotypic correlations between functionally linked floral traits. The five floral traits examined exhibited significant phenotypic integration at all populations, and both the magnitude and the pattern of integration differed widely among populations. Variation in extent and pattern of integration was neither distance‐dependent nor significantly related to between‐population variation in taxonomical composition and morphological diversity of the pollinator assemblage. Patterns of floral integration were closer to expectations derived from consideration of developmental affinities between floral whorls than to expectations based on a pollinator‐mediated adaptive hypothesis. Taken together, results of this study suggest that between‐population differences in magnitude and pattern of floral integration in H. foetidus are probably best explained as a consequence of random genetic sampling in the characteristically small and ephemeral populations of this species, rather than reflecting the selective action of current pollinators.     

Excess copper in soil as a factor affecting bacterial spots caused by <Emphasis Type="Italic">Xanthomonas vesicatoria</Emphasis> in tomato plants; bio-interaction between two stress factors and their influence on plants

The investigations presented in this paper focus on studying the influence of excess soil copper levels in young tomato plants and their relationship to bacterial spot severity caused by Xanthomonas vesicatoria race T3. The plants were grown under greenhouse conditions in pots containing soil artificially contaminated with copper in concentrations of 250 and 400 mg kg⁻¹. Both stress factors were applied individually and in combination. Soil copper levels did influence bacterial spot severity. The copper doses applied restricted bacterial spot growth. Strongest responses were observed when the pathogen was infiltrated into seeds. Deformations of plant, as well as increased plastid synthesis inhibition occurred when the plants were exposed to copper and X. vesicatoria. The applicability of the investigation is related to the fight against bacterial spot caused by X. vesicatoria in tomatoes grown on copper-polluted soils. In this case, the remedial action should be carried out very carefully in order to avoid additional damage to plants.     

Effects of experimental calcium availability,egg parameters and laying order on Great Tit Parus major eggshell pigmentation patterns

Many bird species lay eggs speckled with protoporphyrin‐based spots, however, for most of them the function of eggshell spotting is unknown. A plausible hypothesis is that protoporphyrin might have a structural function in strengthening the eggshell and is therefore deposited when calcium is scarce. In this study, we experimentally provided Great Tit Parus major females with supplemental calcium to examine its effect on the protoporphyrin‐based maculation of their eggs. In addition, we studied variation in eggshell pigmentation patterns in relation to other egg parameters and laying order. Calcium‐supplemented females laid larger eggs but shell thickness was not significantly affected by the treatment. Calcium supplementation may reduce the time and energy females devote to searching for calcium‐rich material, so that they can collect more nutrients and so lay larger eggs. Furthermore, pigment darkness was associated with egg volume and shape, which suggests that female quality and environmental food availability may also influence the shell pigmentation pattern. Within clutches, later‐laid eggs had larger and darker spots that were distributed more unevenly on the shell surface. This within‐clutch pattern could be explained by the increase in egg volume and egg shape and a decline in shell thickness with egg‐laying order, which characteristics were all related to shell‐spotting pattern. Eggs with a coronal ring had thinner shells, but pigment intensity and spot size were not related to shell thickness. Thus, our results suggest that concentrated spotting distribution may have a mechanical function, supporting the structural‐function hypothesis.     

Female preference for male lateral projection area in <Emphasis Type="Italic">Poecilia reticulata</Emphasis>

The lateral projection area (LPA) hypothesis was investigated by presenting female guppies, Poecilia reticulata with a series of paired males in three experiments. One trait was held constant in each experiment (dorsal fin size in expt I, body size in expt II, and total LPA in expt III) while body: dorsal fin ratio varied. Females spent more time near dummies of greater body and dorsal fin size in experiments I and II. The preference functions based on the first two sets of stimuli showed a similar pattern: the greater the LPA difference between paired dummies, the stronger the preference for the larger of the two. However, in the third experiment, neither fin size, body size, nor any particular dorsal fin + body size combination was preferred. These findings support the LPA hypothesis suggesting that increased LPA is more stimulating to sexually receptive females, and that females consequently prefer larger males. Preference for increased male dorsal fin size/LPA in both P. latipinna and P. mexicana as demonstrated in previous studies, and the more distantly related P. reticulata (shown here) is consistent with common ancestry of the sensory/neural systems in females of all three species and perhaps the entire Poeciliid family.