Comparative phylogeography of diadromous and freshwater daces of the genus <Emphasis Type="Italic">Tribolodon</Emphasis> (Cyprinidae)

Far Eastern daces, genus Tribolodon (Cyprinidae), are thought to have diversified and developed unique diadromous life histories under changing conditions in the Sea of Japan and the surrounding environment. To examine the relationships between life history traits, distribution, and genetic population structures, we conducted a comparative phylogeographic analysis using partial mtDNA sequence data from samples collected over almost the full ranges of all four Tribolodon species. Phylogenetic analyses revealed several intraspecific haplotype groups that differentiated in the early Pleistocene to the Pliocene with or without geographic overlaps. A time-calibrated phylogeny suggested that the relatively smaller geographic ranges of the strictly freshwater species, T. sachalinensis and T. nakamurai, were explained not by the recent origins of these species, but by their limited dispersal abilities and smaller historical population sizes. The wider-ranging diadromous species, T. brandtii and T. hakonensis, exhibited similar major phylogeographic structures in their distributions, but the chronological order and timing of formation of this structure largely differed between the two species. In addition to those differences, the overlapping patterns of the differentiated intraspecific lineages in these species suggest dynamic, but somewhat restricted dispersal during the Plio-Pleistocene. Tribolodon hakonensis, one of the most widespread species of East Asian freshwater fishes, included both common and unique phylogeographic patterns compared to other fish species; the unique patterns (i.e., its wide range across freshwater biogeographic boundaries like the sea and mountains) would reflect its ecological features as a remarkable generalist inhabiting lakes, upper and lower reaches of rivers, and even coastal areas.     

Sexual dimorphism and dichromatism in the cyprinid fish <Emphasis Type="Italic">Puntius titteya</Emphasis>

We documented sexual dimorphism and dichromatism in the cyprinid fish Puntius titteya. We observed no sexual difference in body size, although males had longer fins than females. Male body coloration was redder and exhibited a higher saturation than that of females. However, in females, coloration in the cheek (around the gill cover) was near red and exhibited high saturation compared to coloration of the abdomen. These results clearly indicate sexual dimorphism in fin size and dichromatism in P. titteya, which suggests that this species has a high potential use as a model for studying sexual selection.     

Investigating the behavioral significance of color pattern in a cichlid fish: firemouths <Emphasis Type="Italic">Thorichthys meeki</Emphasis> respond differently to color-manipulated video and dummy conspecifics

Red coloration is a conspicuous feature of many visual signals and can function to attract or deter its viewers. Among fishes, red is associated with specialized nuptial, territorial and aposematic (warning) displays. Both sexes of the firemouth cichlid fish Thorichthys meeki develop red ventral coloration at sexual maturity, along with temporally variable black (melanic) elements. Isolated adult firemouth cichlids sequentially presented paired dummy and paired video conspecifics, both with and without red ventral coloration. Subjects interacted more with red-containing stimuli, but with a significant interaction: dummy presentations revealed a strong, positive red bias that video presentations did not. In addition, the melanic color pattern displayed by subjects at the initiation of each trial had a significant effect on subject responsiveness. These results reveal the potential for between-subject differences and experimental design parameters to interact critically in the study of animal color patterns.     

Three new species of <Emphasis Type="Italic">Russula</Emphasis> from South China

Russula lotus, R. nivalis, and R. purpureoverrucosa are proposed here as new taxa based on morphological and molecular evidences. The new species are described with illustration photographs and line drawings, and compared against related species. Morphologically, R. lotus (subgenus Heterophyllidia, section Heterophyllae, subsection Cyanoxanthinae) is characterized by a medium-sized basidioma with a pale pink to purplish pink pileus whose center area is yellowish white, white to cream white lamellae occasionally forked with lamellulae, a cream white smooth stipe, broadly ellipsoid to ellipsoid basidiospores ornamented with disconnected amyloid warts and inamyloid suprahilar plage, dispersed sulphovanillin (SV)-negative pileocystidia, and the pileipellis with suprapellis cells claw-assembled. Russula nivalis (subgenus Russula, section Russula, subsection Russula) is characterized by a very small pure white basidioma with a pileus 7–12 mm in diameter, abundant clavate pileocystidia and caulocystidia changing purplish red in SV, and broadly ellipsoidal to ellipsoid basidiospores ornamented with strongly amyloid warts and ridges interconnected by fine lines in an uncompleted or completed reticulum, mostly with inamyloid suprahilar plage. Russula purpureoverrucosa (subgenus Incrustatula, section Lilaceinae, subsection Lilaceinae) is characterized by a medium-sized basidioma with a red to grayish magenta pileus slightly areolate in small irregular warts from center to margin, a stipe with the same color and warts as the pileus, white to cream white occasionally forked lamellae with lamellulae, broadly ellipsoidal to ellipsoid basidiospores ornamented with amyloid warts and ridges rarely connected, abundant clavate pleurocystidia covered with thick yellowish incrustations, and the pileipellis with suprapellis cells a typical trichoderm, some of which covered with yellowish incrustations, pileocystidia absent. Phylogenetic analysis of nucleotide sequences of the internal transcribed spacer (ITS) region provided further evidence that the described species belong to the subsections above respectively, and represent new taxa.     

Variance in reproductive success and the opportunity for selection in a serially monogamous species: simulations of the mating system of <Emphasis Type="Italic">Tropheus</Emphasis> (Teleostei: Cichlidae)

Sexual selection is believed to play a major role in speciation processes of cichlid fishes in the East African Great Lakes, in particular Lakes Malawi and Victoria, by driving diversification in male nuptial coloration. In Lake Tanganyika, a high rate of color pattern diversification is found in the genus Tropheus, where more than 100, mostly allopatric, color morphs have been described. Whether color pattern differentiation in Tropheus could follow from sexual selection as well, has not yet been conclusively shown. Unlike typical sexually selected species, Tropheus are sexually monomorphic, establish temporary pair bonds and spawn monogamously. Variance in mating success among individuals would still allow for sexual selection, but due to their high population census sizes, parentage data from natural populations are difficult to obtain. Simulations designed according to existing data on mating behavior in Tropheus suggested that variance in male reproductive success can be substantial and lead to levels of opportunity for selection, which are similar to values estimated, for example, from natural populations of sexually dimorphic songbirds. Variance in male success was mostly affected by the way females perceived and reacted to differences between males, and to a lesser extent by the duration of components of the reproductive cycles of males and females. These results indicate that future work on the importance of sexual selection in Tropheus should concentrate on mate choice cues and female mate choice behavior, but does not depend critically on the acquisition of more detailed life history data.     

Identification of functional <Emphasis Type="Italic">flavonol synthase</Emphasis> genes from fragrant wild cyclamen (<Emphasis Type="Italic">Cyclamen purpurascens</Emphasis>)

Cyclamen purpurascens is considered suitable for horticultural breeding of cyclamens because it has an attractive fragrance that is not found in other wild species. To improve the commercial value of cyclamen flowers, this fragrance has been introduced into ornamental cultivars. However, variation in flower color is somewhat limited in these cultivars, and therefore understanding the genetic networks of flower coloration in C. purpurascens is required. We previously isolated DNA fragments of anthocyanin biosynthetic genes from C. purpurascens, broadening our understanding of the biosynthetic pathway of flavonols, which are co-pigments in flower coloration. In this study, we isolated complete open reading frames of flavonol synthase genes from C. purpurascens (CpurFLS1 and CpurFLS2) and analyzed the in planta functions of the genes by molecular complementation assay using the fls mutant of Arabidopsis thaliana. Expression patterns in several organs of C. purpurascens were also determined. The results strongly suggest that the CpurFLS genes participate in flavonol synthesis. We discuss the involvement of these two FLSs in flower coloration in C. purpurascens.     

The Mating Behavior of an Undescribed Species of <Emphasis Type="Italic">Rhamphomyia</Emphasis> (Diptera: Empididae)

An undescribed sex-role reversed species of an empidid fly in the genus Rhamphomyia exhibits several unusual behavioral features including the early morning and early evening formation of female swarms low in open woodlands, high in treetops, and over grassy hayfields. These swarms only last between 1 and 2 h each and are composed of females with highly ornamented legs that they hold around their narrow abdomens, which they do not inflate in the manner of R. longicauda and some other members of the genus. Males visit the swarms carrying small insects as nuptial gifts that they transfer to the partners they choose as do males of some other sex-role reversed empidids.     

Investigation of karyotypic composition and evolution in <Emphasis Type="Italic">Lilium</Emphasis> species belonging to the section martagon

Analyzing chromosomal traits is one of the pragmatic ways to establish evolutionary and genetic database of plants that has complicated phylogenetic system. There are some conflicts on the exact phylogeny and evolutionary pathway of Lilium, and section martagon is the most complicated part among them. In this study, chromosomal traits of martagon lily species are described. All martagon lilies were analyzed with FISH (Fluorescence in situ hybridization) technique, followed by detailed karyotyping. Each species showed 2n = 2x = 24 of chromosome complement. Size of chromosomes ranged from 451.04 to 680.06 µm. 5S and 45S ribosomal DNA, general molecular markers in modern evolutionary research were used as probe in this study. Variation in rDNA loci and chromosome translocation were observed in Lilium hansonii; the highest number of 45S rDNA loci was detected in Lilium hansonii, followed by other martagon lilies, in similar locations but with differences, and chromosome translocation was observed from one individual of Lilium hansonii. Additionally, Lilium tsingtauense from Jeju-do Island, Korea was detected with two extra chromosomes. These kind of genetic variations through karyotyping indicate ongoing genetic variations in martagon lilies. In this study, precise analysis of chromosome traits in Lilium species belonging to section martagonperformed to contribute to better comprehension of the evolutionary pathway and establishment of cytogenetic database for further plant breeding research.     

Association between expression levels and growth trait-related SNPs located in promoters of the <Emphasis Type="Italic">MC4R</Emphasis> and <Emphasis Type="Italic">MSTN</Emphasis> genes in <Emphasis Type="Italic">Spinibarbus hollandi</Emphasis>

Melanocortin 4 receptor: (MC4R) and Myostatin (MSTN) are two important growth trait-related genes in animals. In this study, we showed that two SNPs, MC4R-719A>G and MSTN-519C>T, found in the promoters of the MC4R and MSTN genes, respectively, are both associated with growth traits in Spinibarbus hollandi. Furthermore, we observed that there were significant associations between the expression levels of the MC4R and MSTN genes and these two growth trait-related SNPs. The expression level of MC4R gene in brain was lower in GG genotype fish with extremely high growth performance than that in AA genotype fish with extremely low growth performance. Expression level of the MSTN gene in muscle was lower in TT genotype fish with extremely high growth performance than that in CC and CT genotype fish with lower growth performance. The results indicated that these SNPs located in the promoters of MC4R and MSTN are associated with growth-related traits through modification of gene expression levels. The MSTN and MC4R SNPs may have useful application in effective marker-assisted selection aimed to increase output in S. hollandi.     

Latitudinal Influence on the Sexual Dimorphism of the Marine Fish <Emphasis Type="Italic">Bathygobius soporator</Emphasis> (Gobiidae: Teleostei)

Environmental gradients in a marine setting may have significant effects on morphological variations and evolutionary patterns, including sexual dimorphism variations within and between fish populations. We analyzed sexual shape and size dimorphism in accordance with Rensch and Bergmann’s rules in five coastal populations of the gobiid Bathygobius soporator along 4000 km of the Brazilian coastline. The populations differ significantly in sexual body shape dimorphism, with a tendency toward reduced intrapopulation dimorphism, increasing with latitude. Body size variation was significant between populations and population vs. sex, and inverse to Bergmann’s rule. Moreover, size dimorphism among populations of B. soporator does not follow Rensch’s rule. These data represent a rare example of inter and intrapopulation spatial variation in sexual dimorphism associated with latitude in marine fish. This suggests a complex and particularized scenario of biotic and abiotic interactions acting on local populations of B. soporator in extensive coastal areas of the Western Atlantic, with profound implications for species evolution.     

Development of INDELs markers in oilseed rape (<Emphasis Type="Italic">Brassica napus</Emphasis> L.) using re-sequencing data

Insertions/deletions (INDELs), a type of abundant length polymorphisms in the plant genomes, combine the characteristics of both simple sequence repeats (SSRs) and single-nucleotide polymorphisms (SNP), and thus can be developed as desired molecular markers for genetic studies and crop breeding. There has been no large-scale characterization of INDELs variations in Brassica napus yet. In this study, we identified a total of 538,691 INDELs in size range of 1–10 bp by aligning whole-genome re-sequencing data of 23 B. napus inbred lines (ILs) to the B. napus genome sequence of ‘Darmor-bzh.’ Of these, 104,190 INDELs were uniquely mapped on the pseudochromosomes of the reference genome. A set of 595 unique INDELs of 2–5 bp in length was selected for experimental validation in the 23 ILs. Of these INDELs, 530 (89.01 %) produced a single PCR product and were single locus. A total of 523 (87.9 %) INDELs were found polymorphic among the 23 ILs. A genetic linkage map containing 108 single-locus INDELs and 89 anchor SSR markers was constructed using 188 recombinant ILs. The majority of INDELs markers on the linkage map showed consistency with the pseudochromosomes of the B. napus cultivar ‘Darmor-bzh.’ The INDELs variations and markers reported here will be valuable resources in future for genetic studies and molecular breeding in oilseed rape.     

Infestation with the parasitic nematode <Emphasis Type="Italic">Philometra ovata</Emphasis> does not impair behavioral sexual competitiveness or odor attractiveness of the male European minnow (<Emphasis Type="Italic">Phoxinus phoxinus</Emphasis>)

Our understanding on the role of chemical signals in parasite-mediated sexual selection is still limited, and only some existing studies have focused on fish. Furthermore, published studies on the effect of parasite infection on behavioral sexual competition of the male hosts have yielded contradictory results. Here, we examined whether the infection of the body cavity-dwelling parasitic nematode Philometra ovata influences odor-based female choice and behavioral sexual competition (dominance and courtship behavior) between males in the European minnow (Phoxinus phoxinus), the cyprinid fish host. In contrast to our predictions, we found that naïve females showed no preference between the odors of infected and non-infected males, thus indicating that P. ovata infection may not affect odor-based female choice. Moreover, P. ovata did not impair sexual competitiveness of their hosts either. Our results indicate that despite its relatively large size, P. ovata may not alter sexual cues and the success of the male hosts in sexual selection.     

Continued feeding on <Emphasis Type="Italic">Diporeia</Emphasis> by deepwater sculpin in Lake Huron

Monitoring changes in diets of fish is essential to understanding how food web dynamics respond to changes in native prey abundances. In the Great Lakes, Diporeia, a benthic macroinvertebrate and primary food of native benthivores, declined following the introduction of invasive Dreissena mussels and these changes were reflected in fish diets. We examined the diets of deepwater sculpin Myoxocephalus thompsonii collected in bottom trawls during 2010–2014 in the main basin of Lake Huron, and compared these results to an earlier diet study (2003–2005) to assess if their diets have continued to change after a prolonged period of Dreissena mussel invasion and declined Diporeia densities. Diporeia, Mysis, Bythotrephes, and Chironomidae were consumed regularly and other diet items included ostracods, copepods, sphaerid clams, and fish eggs. The prey-specific index of relative importance calculated for each prey group indicated that Mysis importance increased at shallow (≤55 m) and mid (64–73 m) depths, while Diporeia importance increased offshore (≥82 m). The average number of Diporeia consumed per fish increased by 10.0% and Mysis decreased by 7.5%, while the frequency of occurrence of Diporeia and Mysis remained comparable between time periods. The weight of adult deepwater sculpin (80 mm and 100 mm TL bins) increased between time periods; however, the change in weight was only significant for the 80 mm TL group (p?<?0.01). Given the historical importance of Diporeia in the Great Lakes, the examination of deepwater sculpin diets provides unique insight into the trophic dynamics of the benthic community in Lake Huron.     

Exploiting the <Emphasis Type="Italic">Rht</Emphasis> portfolio for hybrid wheat breeding

Key message

The portfolio of available Reduced height loci (Rht-B1, Rht-D1, and Rht24) can be exploited for hybrid wheat breeding to achieve the desired heights in the female and male parents, as well as in the hybrids, without adverse effects on other traits relevant for hybrid seed production.

Abstract

Plant height is an important trait in wheat line breeding, but is of even greater importance in hybrid wheat breeding. Here, the height of the female and male parental lines must be controlled and adjusted relative to each other to maximize hybrid seed production. In addition, the height of the resulting hybrids must be fine-tuned to meet the specific requirements of the farmers in the target regions. Moreover, this must be achieved without adversely impacting traits relevant for hybrid seed production. In this study, we explored Reduced height (Rht) loci effective in elite wheat and exploited their utilization for hybrid wheat breeding. We performed association mapping in a panel of 1705 wheat hybrids and their 225 parental lines, which besides the Rht-B1 and Rht-D1 loci revealed Rht24 as a major QTL for plant height. Furthermore, we found that the Rht-1 loci also reduce anther extrusion and thus cross-pollination ability, whereas Rht24 appeared to have no adverse effect on this trait. Our results suggest different haplotypes of the three Rht loci to be used in the female or male pool of a hybrid breeding program, but also show that in general, plant height is a quantitative trait controlled by numerous small-effect QTL. Consequently, marker-assisted selection for the major Rht loci must be complemented by phenotypic selection to achieve the desired height in the female and male parents as well as in the wheat hybrids.

     

Variation in the population demographics of <Emphasis Type="Italic">Scolopsis bilineatus</Emphasis> in response to predators

Predatory fishes play critical roles in the trophodynamics of coral reefs, and the biomass of predatory fish can be a strong determinant of the structure of reef fish assemblages. In this study, we used variations in predator biomass between management zones on the Great Barrier Reef to examine how predators influence the biomass, mortality, condition, and reproductive potential of a common prey species Scolopsis bilineatus (bridled monocle bream; Nemipteridae). Despite no numerical differences in biomass or mortality, we found significant differences in a variety of demographic traits for S. bilineatus between multiple areas of high and low predator biomass. The size-at-age, condition, and reproductive potential of fish were reduced in marine reserves where predator biomass was high. The response of fish to predators was highly sex dependent; females suffered the greatest reductions in condition and reproductive potential. This study supports the notion that predators can play important roles in regulating prey dynamics and emphasises the importance of understanding top-down control by predators when considering fisheries management techniques and conservation strategies.     

Genetic drift and uniform selection shape evolution of most traits in <Emphasis Type="Italic">Eugenia dysenterica</Emphasis> DC. (Myrtaceae)

Knowing how microevolutionary processes, such as genetic drift and natural selection, shape variation in adaptive traits is strategic for conservation measures. One way to estimate local adaptation is to compare divergences in quantitative traits (Q_ST) and neutral loci (F_ST). Therefore, we have assessed the pattern of phenotypic and molecular genetic divergence among natural subpopulations of the fruit tree Eugenia dysenterica DC. A provenance and progeny test was performed to assess the quantitative traits of the subpopulations collected in a wide distribution area of the species in the Brazilian Cerrado. The sampled environments are in a biodiversity hotspot with heterogeneous soil and climate conditions. By associating quantitative trait variation in initial seedling development with neutral microsatellite marker variation, we tested the local adaptation of the traits by the Q_ST–F_ST contrast. Genetic drift was prevalent in the phenotypic differentiation among the subpopulations, although the traits seedling emergence time and root green mass, which are relevant for adaptation to the Cerrado climate, showed signs of uniform selection. Our results suggest that E. dysenterica has a spatial genetic structure divided into two large groups, separated by a line that divides the Cerrado biome in a southwestern to northeastern direction. This structure must be taken into account for managing E. dysenterica genetic resources both for conservation and breeding purposes.     

Integrated analysis of leaf morphological and color traits in different populations of Chinese cabbage (<Emphasis Type="Italic">Brassica rapa</Emphasis> ssp. <Emphasis Type="Italic">pekinensis</Emphasis>)

Key message

QTLs and candidate gene markers associated with leaf morphological and color traits were identified in two immortalized populations of Brassica rapa, which will provide genetic information for marker-assisted breeding.

Abstract

Brassica rapa is an important leafy vegetable consumed worldwide and morphology is a key character for its breeding. To enhance genetic control, quantitative trait loci (QTLs) for leaf color and plant architecture were identified using two immortalized populations with replications of 2 and 4 years. Overall, 158 and 80 QTLs associated with 23 and 14 traits were detected in the DH and RIL populations, respectively. Among them, 23 common robust-QTLs belonging to 12 traits were detected in common loci over the replications. Through comparative analysis, five crucifer genetic blocks corresponding to morphology trait (R, J&U, F and E) and color trait (F, E) were identified in three major linkage groups (A2, A3 and A7). These might be key conserved genomic regions involved with the respective traits. Through synteny analysis with Arabidopsis, 64 candidate genes involved in chlorophyll biosynthesis, cell proliferation and elongation were co-localized within QTL intervals. Among them, SCO3, ABI3, FLU, HCF153, HEMB1, CAB3 were mapped within QTLs for leaf color; and CYCD3;1, CYCB2;4, AN3, ULT1 and ANT were co-localized in QTL regions for leaf size. These robust QTLs and their candidate genes provide useful information for further research into leaf architecture with crop breeding.

     

Estimates of Heritability for Growth and Shell Color Traits and Their Genetic Correlations in the Black Shell Strain of Pacific Oyster <Emphasis Type="Italic">Crassostrea gigas</Emphasis>

The Pacific oyster Crassostrea gigas has been introduced widely and massively and became an economically important aquaculture species on a global scale. We estimated heritabilities of growth and shell color traits and their genetic correlations in black shell strain of C. gigas. Analyses were performed on 22 full-sib families in a nested mating design including 410 individuals at harvest (24 months of age). The parentage assignment was inferred based on four panels of multiplex PCR markers including 10 microsatellite loci and 94.9% of the offspring were unambiguously assigned to single parent pairs. The Spearman correlation test (r = ? 0.992, P < 0.001) demonstrated the high consistency of the shell pigmentation (SP) and L* and their same efficacy in shell color measurements. The narrow-sense heritability estimated under the animal model analysis was 0.18 ± 0.12 for shell height, 0.25 ± 0.16 for shell length, 0.10 ± 0.09 for shell width, 0.42 ± 0.20 for total weight, 0.32 ± 0.18 for shell weight, and 0.68 ± 0.16 for L*, 0.69 ± 0.16 for shell pigmentation, respectively. The considerable additive genetic variation in growth and shell color traits will make it feasible to produce genetic improvements for these traits in selective breeding program. High genetic and phenotypic correlations were found among growth traits and among shell color traits. To optimize a selection strategy for both fast growth and pure dark shell strain of C. gigas, it is proposed to take both total weight and black shell as joint objective traits in selective breeding program. Our study offers an important reference in the process of selective breeding in black shell color stain of C. gigas and will facilitate to develop favorable breeding strategies of genetic improvements for this economically important strain.     

The expression level of anthocyanidin synthase determines the anthocyanin content of crabapple (<Emphasis Type="Italic">Malus</Emphasis> sp.) petals

In addition to contributing to the coloration of plant organs and their defense against herbivores, the consumption of anthocyanins in the human diet has a number of health benefits. Crabapple (Malus sp.) represents a valuable experimental model system to research the mechanisms and regulation of anthocyanin accumulation, in part due to the often vivid and varied petal and leaf coloration that is exhibited by various cultivars. The enzyme anthocyanidin synthase (ANS) plays a pivotal role in anthocyanin biosynthesis; however, the relationship between ANS expression and petal pigmentation has yet to be established in crabapple. To illuminate the mechanism of anthocyanin accumulation in crabapple petals, we evaluated the expression of two crabapple ANS allelic genes (McANS-1 and McANS-2) and the levels of anthocyanins in petals from cultivars with dark red (‘Royalty’) and white (‘Flame’) petals, as well as another (‘Radiant’) whose petals have an intermediate pink color. We determined that the expression of McANS in the three cultivars correlated with the variation of anthocyanin accumulation during different petal developmental stages. Furthermore, transgenic tobacco plants constitutively overexpressing one of the two McANS genes, McANS-1, had showed elevated anthocyanin accumulation and a deeper red coloration in their petals than those from untransformed control lines. In conclusion, we propose that McANS are responsible for anthocyanin accumulation during petal coloration in different crabapple cultivars.