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1.
Zootaxa ; 4778(2): zootaxa.4778.2.1, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-33055819

RESUMO

Osmia (Hemiosmia), O. (Tergosmia) and O. (Erythrosmia) are three related Palaearctic osmiine bee subgenera (Megachilidae, Megachilinae, Osmiini) comprising eight, seven and four species, respectively. Analysis of female pollen loads and field observations revealed that the species of both O. (Hemiosmia) and O. (Tergosmia) have a distinct or even exclusive preference for Fabaceae as pollen hosts. Species of O. (Erythrosmia) also collect pollen on Fabaceae, but additionally frequently visit nototribic flowers of Lamiaceae and Antirrhineae (Plantaginaceae), which they exploit by rubbing a specialized facial pilosity over the raised anthers. The representatives of O. (Hemiosmia) and the basal members of O. (Tergosmia) build their brood cells in self-excavated burrows in the ground, whereas the more derived O. (Tergosmia) species as well as the O. (Erythrosmia) species place them in preexisting cavities above-ground, which are empty snail shells hidden under prominences of rocks or under stones in the latter subgenus. In O. (Hemiosmia) and O. (Tergosmia), the brood cells are entirely constructed from foreign material and either consist of chewed leaves ("leaf pulp") in the former subgenus or are distinctly three-layered with a thin layer of mud sandwiched between two layers of large pieces of petals in the latter subgenus. In O. (Erythrosmia), the brood cells within the shell whorls are delimited by one-layered partitions of leaf pulp and the nests are closed by a barricade of densely packed small particles followed by a double wall of leaf pulp at the shell opening. The taxonomic revision of the three subgenera revealed the existence of an undescribed species, O. (Hemiosmia) spinicoxa spec. nov., which occurs in southwestern Morocco. The subgenus O. (Ozbekosmia) Zanden, 1994 syn. nov. is newly put into synonymy with O. (Tergosmia) Warncke, 1988. Osmia (Tergosmia) rhodoensis arquata Warncke, 1988 syn. nov. and O. (Tergosmia) tergestensis ononidis Ferton, 1897 syn. nov. are no longer accepted as valid subspecies of O. (Tergosmia) rhodoensis (Zanden, 1983) and O. (Tergosmia) tergestensis Ducke, 1897, respectively. Identification keys for all species of the three subgenera are given.


Assuntos
Abelhas , Fabaceae , Comportamento de Nidação , Animais , Feminino , Flores , Pólen
2.
Nat Commun ; 11(1): 4916, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004803

RESUMO

Self-incompatibility (SI) is a breeding system that promotes cross-fertilization. In Brassica, pollen rejection is induced by a haplotype-specific interaction between pistil determinant SRK (S receptor kinase) and pollen determinant SP11 (S-locus Protein 11, also named SCR) from the S-locus. Although the structure of the B. rapa S9-SRK ectodomain (eSRK) and S9-SP11 complex has been determined, it remains unclear how SRK discriminates self- and nonself-SP11. Here, we uncover the detailed mechanism of self/nonself-discrimination in Brassica SI by determining the S8-eSRK-S8-SP11 crystal structure and performing molecular dynamics (MD) simulations. Comprehensive binding analysis of eSRK and SP11 structures reveals that the binding free energies are most stable for cognate eSRK-SP11 combinations. Residue-based contribution analysis suggests that the modes of eSRK-SP11 interactions differ between intra- and inter-subgroup (a group of phylogenetically neighboring haplotypes) combinations. Our data establish a model of self/nonself-discrimination in Brassica SI.


Assuntos
Brassica rapa/fisiologia , Melhoramento Vegetal , Proteínas de Plantas/metabolismo , Proteínas Quinases/metabolismo , Animais , Cristalografia , Flores/metabolismo , Haplótipos , Simulação de Dinâmica Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/ultraestrutura , Pólen/metabolismo , Ligação Proteica/fisiologia , Domínios Proteicos/fisiologia , Proteínas Quinases/genética , Proteínas Quinases/ultraestrutura , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/ultraestrutura , Células Sf9 , Spodoptera
3.
Zootaxa ; 4803(1): zootaxa.4803.1.9, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-33056036

RESUMO

The genus Criorhina consists of honey-bee and bumblebee mimic flower flies with a strongly produced face. It is widespread in the Holarctic and Oriental Regions. Criorhina adults are usually found flying near white spring flowers in woodlands and shrubs. The Chinese Criorhina fauna is poorly known and includes seven species. In our flower fly collection of Henan Province, northern China, an eighth new species was discovered: Criorhina rostrata Li, Huo Li sp. nov. This new species is here described and illustrated. The new species possess a very long proboscis, unique amongst the Criorhina species from mainland China. In addition, during the course of this study, Criorhina brevipila Loew, 1871 was also found to be present in mainland China, based on a specimen from our collection. A key to the species of Criorhina from mainland China is given.


Assuntos
Flores , Florestas , Animais , Abelhas , China
4.
Zootaxa ; 4789(1): zootaxa.4789.1.3, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33056445

RESUMO

All available type materials of the Indochinese genus Goliathopsis Janson, 1881 are determined, and lectotype designations are made for G. capreolus Gestro 1888, G. despectus (Westwood, 1873), G. esquiroli Pouillaude, 1913, and G. velutinus Pouillaude, 1913. The examination of type series revealed three synonyms: Goliathopsis camptotropus Yang, 1988 new synonym and G. polystricus Yang, 1988 new synonym are synonymized with G. esquiroli, and G. maolanus Yang, 1988 new synonym is regarded as a junior synonym of G. lameyi Fairmaire, 1893. Besides, G. cervus Janson, 1881 is proved to be a valid species. Diagnoses, key, and color illustrations are provided for all species. All known distribution records are mapped, and the location of "Tsékou" and "Oui-Sy" are presented and discussed.


Assuntos
Besouros , Distribuição Animal , Estruturas Animais , Animais , China , Flores
5.
Am J Bot ; 107(9): 1260-1273, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32984956

RESUMO

PREMISE: Defense investment in plant reproductive structures is relatively understudied compared to the defense of vegetative organs. Here the evolution of chemical defenses in reproductive structures is examined in light of the optimal defense, apparency, and resource availability hypotheses within the genus Cornus using a phylogenetic comparative approach in relation to phenology and native habitat environmental data. METHODS: Individuals representing 25 Cornus species were tracked for reproductive phenology over a full growing season at the Arnold Arboretum of Harvard University. Floral, fruit, and leaf tissue was sampled to quantify defensive chemistry as well as fruit nutritional traits relevant to bird dispersal. Native habitat environmental characteristics were estimated using locality data from digitized herbarium records coupled with global soil and climate data sets. RESULTS: The evolution of later flowering was correlated with increased floral tannins, and the evolution of later fruiting was correlated with increased total phenolics. Leaves were found to contain the highest tannin activity, while inflorescences contained the highest total flavonoids. Multiple aspects of fruit defensive chemistry were correlated with fruit nutritional traits. Floral and fruit defensive chemistry were evolutionarily correlated with aspects of native habitat temperature, precipitation, and soil characteristics. CONCLUSIONS: Results provide tentative support for the apparency hypothesis with respect to both flower and fruit phenology, while relative concentrations of secondary metabolites across organs provide mixed support for the optimal defense hypothesis. The evolution of reproductive defense with native habitat provides, at best, mixed support for the resource availability hypothesis.


Assuntos
Cornus , Animais , Flores , Frutas , Inflorescência , Filogenia , Folhas de Planta
6.
Am J Bot ; 107(9): 1274-1282, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32895943

RESUMO

PREMISE: It has been hypothesized that pollination success in animal-pollinated dioecious plants relies on opportunistic pollinators with no discrimination against female flowers. However, empirical studies of pollinator foraging behavior and pollination effectiveness in dioecious species are few. METHODS: To investigate potential pollinators in Helwingia japonica, a dioecious shrub with small, inconspicuous flowers, we compared floral visitors and visit frequency to female and male plants for three flowering seasons in two field populations in subtropical forests in southwest China. Pollen placement on the insect bodies of four groups (solitary bees and other bees, fungus gnats, and other flies) was compared, and insect foraging behavior was observed. Pollen removal and conspecific and heterospecific pollen deposition per visit were measured to compare pollination effectiveness among the four groups. RESULTS: Floral visitors usually did not discriminate between male and female flowers and did not gather pollen into collections. Our measurements of pollen transfer efficiency showed that solitary bees were the most effective pollinators with the highest conspecific pollen deposition. These insects seemed to be opportunistic visitors because pollen grains of H. japonica were distributed evenly over different regions of the visitor's body, and heterospecific pollen accounted for over 50% of total pollen loads on stigmas in the two populations. CONCLUSIONS: Our investigations indicated that potential pollinators were generalists and did not discriminate against female flowers, as predicted for dioecious species pollinated by insects. A perspective of pollen removal by floral visitors offers insights into the evolution of plant sexual systems.


Assuntos
Insetos , Polinização , Animais , Abelhas , China , Feminino , Flores , Masculino , Pólen
7.
PLoS One ; 15(9): e0237561, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32877468

RESUMO

In increasingly urban landscapes, the loss of native pollen and nectar floral resources is impacting ecologically important pollinators. Increased urbanization has also brought about the rise of urban gardens which introduce new floral resources that may help replace those the pollinators have lost. Recently, studies have shown that the microbial communities of nectar may play an important role in plant-pollinator interactions, but these microbial communities and the floral visitors in urban environments are poorly studied. In this study we characterized the floral visitors and nectar microbial communities of Ascelpias curassavica, a non-native tropical milkweed commonly, in an urban environment. We found that the majority of the floral visitors to A. curassavica were honey bees followed closely by monarch butterflies. We also found that there were several unique visitors to each site, such as ants, wasps, solitary bees, several species of butterflies and moths, Anna's hummingbird, and the tarantula hawk wasp. Significant differences in the nectar bacterial alpha and beta diversity were found across the urban sites, although we found no significant differences among the fungal communities. We found that the differences in the bacterial communities were more likely due to the environment and floral visitors rather than physiological differences in the plants growing at the gardens. Greater understanding of the impact of urbanization on the nectar microbiome of urban floral resources and consequently their effect on plant-pollinator relationships will help to predict how these relationships will change with urbanization, and how negative impacts can be mitigated through better management of the floral composition in urban gardens.


Assuntos
Asclepias/microbiologia , Microbiota , Néctar de Plantas , Clima Tropical , Urbanização , Bactérias/crescimento & desenvolvimento , Biodiversidade , Flores/microbiologia , Fungos/crescimento & desenvolvimento
8.
Medicine (Baltimore) ; 99(37): e22179, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32925789

RESUMO

BACKGROUND: Assessing the effectiveness and safety of plum-blossom needle for (COVID-19) related headache is the main purpose of this systematic review protocol. METHODS: We will search the following sources for the identification of trials: The Cochrane Library, PubMed, EMBASE, Chinese Biomedical Literature Database (CBM), Chinese National Knowledge Infrastructure Database (CNKI), Chinese Science and Technique Journals Database (VIP), and the Wanfang Database. The searches were limited to articles published in 2020, but no language restrictions were imposed. Only include randomised controlled trials (RCTs), with or without blinding, and participant or observer reported outcomes, will be included.The primary outcome is the time and rate of appearance of headache induced by COVID-19. The secondary outcome is the length of hospital stay. Two independent reviewers will conduct the study selection, data extraction and assessment. Review Manager Software V.5.3 will be used for the assessment of risk of bias and data synthesis. RESULTS: The results will provide a high-quality synthesis of current evidence for researchers in this subject area. CONCLUSION: The conclusion of our study will provide an evidence to judge whether plum-blossom needle is effective and safe for COVID-19-related headache. ETHICS AND DISSEMINATION: This protocol will not evaluate individual patient information or affect patient rights and therefore does not require ethical approval. Results from this review will be disseminated through peer-reviewed journals and conference reports. PROSPERO REGISTRATION NUMBER: CRD42020199508.


Assuntos
Terapia por Acupuntura , Infecções por Coronavirus , Cefaleia , Pandemias , Pneumonia Viral , Prunus domestica , Terapia por Acupuntura/instrumentação , Terapia por Acupuntura/métodos , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/terapia , Flores , Cefaleia/etiologia , Cefaleia/terapia , Humanos , Medicina Tradicional Chinesa , Metanálise como Assunto , Agulhas , Pneumonia Viral/epidemiologia , Pneumonia Viral/fisiopatologia , Pneumonia Viral/terapia , Projetos de Pesquisa , Revisões Sistemáticas como Assunto , Resultado do Tratamento
9.
Proc Biol Sci ; 287(1934): 20201525, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32873200

RESUMO

Honeybees forage on diverse flowers which vary in the amount and type of rewards they offer, and bees are challenged with maximizing the resources they gather for their colony. That bees are effective foragers is clear, but how bees solve this type of complex multi-choice task is unknown. Here, we set bees a five-comparison choice task in which five colours differed in their probability of offering reward and punishment. The colours were ranked such that high ranked colours were more likely to offer reward, and the ranking was unambiguous. Bees' choices in unrewarded tests matched their individual experiences of reward and punishment of each colour, indicating bees solved this test not by comparing or ranking colours but by basing their colour choices on their history of reinforcement for each colour. Computational modelling suggests a structure like the honeybee mushroom body with reinforcement-related plasticity at both input and output can be sufficient for this cognitive strategy. We discuss how probability matching enables effective choices to be made without a need to compare any stimuli directly, and the use and limitations of this simple cognitive strategy for foraging animals.


Assuntos
Abelhas/fisiologia , Animais , Comportamento Animal , Comportamento de Escolha , Cor , Percepção de Cores , Simulação por Computador , Flores
10.
Ecol Lett ; 23(10): 1488-1498, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32808477

RESUMO

Floral plantings are promoted to foster ecological intensification of agriculture through provisioning of ecosystem services. However, a comprehensive assessment of the effectiveness of different floral plantings, their characteristics and consequences for crop yield is lacking. Here we quantified the impacts of flower strips and hedgerows on pest control (18 studies) and pollination services (17 studies) in adjacent crops in North America, Europe and New Zealand. Flower strips, but not hedgerows, enhanced pest control services in adjacent fields by 16% on average. However, effects on crop pollination and yield were more variable. Our synthesis identifies several important drivers of variability in effectiveness of plantings: pollination services declined exponentially with distance from plantings, and perennial and older flower strips with higher flowering plant diversity enhanced pollination more effectively. These findings provide promising pathways to optimise floral plantings to more effectively contribute to ecosystem service delivery and ecological intensification of agriculture in the future.


Assuntos
Ecossistema , Polinização , Agricultura , Abelhas , Biodiversidade , Europa (Continente) , Flores , Nova Zelândia , América do Norte , Controle de Pragas
11.
Nat Commun ; 11(1): 4019, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782255

RESUMO

Phenotypic plasticity, the ability of a genotype of producing different phenotypes when exposed to different environments, may impact ecological interactions. We study here how within-individual plasticity in Moricandia arvensis flowers modifies its pollination niche. During spring, this plant produces large, cross-shaped, UV-reflecting lilac flowers attracting mostly long-tongued large bees. However, unlike most co-occurring species, M. arvensis keeps flowering during the hot, dry summer due to its plasticity in key vegetative traits. Changes in temperature and photoperiod in summer trigger changes in gene expression and the production of small, rounded, UV-absorbing white flowers that attract a different assemblage of generalist pollinators. This shift in pollination niche potentially allows successful reproduction in harsh conditions, facilitating M. arvensis to face anthropogenic perturbations and climate change.


Assuntos
Adaptação Fisiológica , Ecossistema , Flores/fisiologia , Polinização , Animais , Abelhas , Brassicaceae/genética , Brassicaceae/fisiologia , Flores/genética , Regulação da Expressão Gênica de Plantas , Interação Gene-Ambiente , Estações do Ano
12.
Nat Commun ; 11(1): 4079, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796936

RESUMO

DNA methylation is an epigenetic modification that specifies the basic state of pluripotent stem cells and regulates the developmental transition from stem cells to various cell types. In flowering plants, the shoot apical meristem (SAM) contains a pluripotent stem cell population which generates the aerial part of plants including the germ cells. Under appropriate conditions, the SAM undergoes a developmental transition from a leaf-forming vegetative SAM to an inflorescence- and flower-forming reproductive SAM. While SAM characteristics are largely altered in this transition, the complete picture of DNA methylation remains elusive. Here, by analyzing whole-genome DNA methylation of isolated rice SAMs in the vegetative and reproductive stages, we show that methylation at CHH sites is kept high, particularly at transposable elements (TEs), in the vegetative SAM relative to the differentiated leaf, and increases in the reproductive SAM via the RNA-dependent DNA methylation pathway. We also show that half of the TEs that were highly methylated in gametes had already undergone CHH hypermethylation in the SAM. Our results indicate that changes in DNA methylation begin in the SAM long before germ cell differentiation to protect the genome from harmful TEs.


Assuntos
Metilação de DNA , Meristema/crescimento & desenvolvimento , Meristema/genética , Oryza/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/genética , Elementos de DNA Transponíveis , Biologia do Desenvolvimento , Epigenômica , Flores , Regulação da Expressão Gênica de Plantas , Inflorescência , Folhas de Planta/metabolismo , Proteínas de Plantas/genética
14.
PLoS One ; 15(8): e0237176, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745128

RESUMO

Some monocotyledonous plants, including liliaceous, amaryllidaceous and iridaceous ones, produce flowers with petaloid tepals in whorls 1 and 2 organs. For explaining the molecular mechanism of two-layered petaloid tepal development, the modified ABC model has been proposed, in which B class genes are expressed in whorl 1 organs as well as in whorls 2 and 3 organs. We have previously obtained results strongly support the modified ABC model by chimeric repressor gene-silencing technology (CRES-T)-mediated suppression of B function in the liliaceous plant Tricyrtis sp. In the present study, we introduced a CRES-T construct derived from the B class gene of Tricyrtis sp. (TrihDEFa-SRDX) into Lilium sp. in order to examine the effect of suppressing B function on the floral organ identity. Flowers of transgenic plants did not open fully and had pale pink-colored tepals with decreased numbers of papillae on the adaxial side in whorls 1 and 2 compared with those of non-transgenic plants. No apparent morphological alterations were observed in whorls 3 and 4 organs. Both the amount of total anthocyanins and the expression levels of endogenous flavonoid biosynthesis-related genes (LhMYB12, LhbHLH2, LhCHS, LhF3H, LhF3'H, LhDFR and LhANS) decreased in whorls 1 and 2 organs of transgenic plants compared with non-transgenic plants. In addition, the expression levels of endogenous B class genes (LFDEF, LFGLOA and LFGLOB) decreased in transgenic plants and the level was negatively correlated with the degree of morphological alteration. Thus suppression of B function may reduce the identity of petaloid tepals in whorls 1 and 2 of transgenic Lilium sp.


Assuntos
Flores/genética , Inativação Gênica , Lilium/genética , Plantas Geneticamente Modificadas/genética , Flores/anatomia & histologia , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
15.
Proc Biol Sci ; 287(1933): 20201191, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32811305

RESUMO

Angiosperm pollen grain diameter varies greatly from a few microns to over 100, but the selective forces driving the interspecific variation in pollen size remain unclear. Although both pre- and post-pollination hypotheses have been proposed, empirical evidence remains scarce. Here we propose that visits by pollen-foraging pollinators have selected against large pollen grains. An association between pollinator behaviour and pollen grain size was confirmed by field studies of 80 flowering species in natural communities, showing that pollinators positively collected pollen in those species with relatively smaller pollen grains but rarely did so in species with larger ones. Allowing for the confounding effects of pollinator type, flower size or style length and pollen grain number, we found a significant effect of pollen-foraging behaviour on variation in pollen grain size, particularly in bee-pollinated plants. While these results suggest that many plant species whose pollen is collected or consumed by pollinators produce small pollen grains, it remains unclear whether pollen grain size is directly affected by pollinator foraging habit or indirectly mediated by pollen number trade-offs.


Assuntos
Magnoliopsida , Pólen , Polinização , Animais , Abelhas , Comportamento Alimentar , Flores
16.
Sci Total Environ ; 747: 141197, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-32777499

RESUMO

Hyperaccumulation describes plants' ability to take up high amounts of soil metals such as Ni and allocate them to aboveground tissues. Little is known, however, about the rate at which Ni is allocated to different plant parts, or about the consumers related to these parts, including their pollinator mutualists. In this study, we examine the interface between the serpentine endemic Ni-hyperaccumulator Odontarrhena lesbiaca and its consumers of different plant parts: leaves (consumers), floral parts (consumers and primitive pollinators), and floral rewards (true pollinators). The study was conducted at two serpentine areas on Lesvos, Greece. Over 13 rounds of sampling during the flowering period of O. lesbiaca in both areas we collected plant stems with flowers, consumers of different plant parts, and flower visitors. Collected animals were mainly insects and some spiders. Chemical analyses showed negligible Ni-concentration differences between the two areas. Among all plant parts, the lowest Ni concentration was found in pollen and the highest in leaves. Regarding animal dietary habits, folivores accumulated the highest Ni concentrations, therefore characterized as "high-Ni insects", while floral-reward consumers, both primary (bees) and secondary (Eristalis tenax, Pygopleurus spp., and wasps), bore low Ni loads. Ni-body load of predators that fed on animals that were passing by was also low. Among floral-reward consumers, short-range fliers (bees of the genera Andrena and Lasioglossum) accumulated higher Ni loads than long-range fliers (Apis mellifera, Bombus terrestris, Eristalis tenax). Solitary Andrena bees accumulated higher Ni concentration than eusocial honeybees (Apis mellifera) and bumblebees (Bombus terrestris); a group of Lasioglossum specimens encompassing both solitary and eusocial bees lay in between. Our results show that diet, foraging distance, and sociality are important factors for Ni transferred into consumers and mutualists, mostly insects that are directly associated with different plant parts of O. lesbiaca.


Assuntos
Brassicaceae , Níquel , Animais , Abelhas , Bioacumulação , Flores , Grécia , Humanos , Polinização
17.
PLoS One ; 15(8): e0236351, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785293

RESUMO

Hybrid performance during wheat breeding can be improved by analyzing genetic distance (GD) among wheat genotypes and determining its correlation with heterosis. This study evaluated the GD between 16 wheat genotypes by using 60 simple sequence repeat (SSR) markers to classify them according to their relationships and select those with greater genetic diversity, evaluate the correlation of the SSR marker distance with heterotic performance and specific combining ability (SCA) for heat stress tolerance, and identify traits that most influence grain yield (GY). Eight parental genotypes with greater genetic diversity and their 28 F1 hybrids generated using diallel crossing were evaluated for 12 measured traits in two seasons. The GD varied from 0.235 to 0.911 across the 16 genotypes. Cluster analysis based on the GD estimated using SSRs classified the genotypes into three major groups and six sub-groups, almost consistent with the results of principal coordinate analysis. The combined data indicated that five hybrids showed 20% greater yield than mid-parent or better-parent. Two hybrids (P2 × P4) and (P2 × P5), which showed the highest performance of days to heading (DH), grain filling duration (GFD), and GY, and had large genetic diversity among themselves (0.883 and 0.911, respectively), were deemed as promising heat-tolerant hybrids. They showed the best mid-parent heterosis and better-parent heterosis (BPH) for DH (-11.57 and -7.65%; -13.39 and -8.36%, respectively), GFD (12.74 and 12.17%; 12.09 and 10.59%, respectively), and GY (36.04 and 20.04%; 44.06 and 37.73%, respectively). Correlation between GD and each of BPH and SCA effects based on SSR markers was significantly positive for GFD, hundred kernel weight, number of kernels per spike, harvest index, GY, and grain filling rate and was significantly negative for DH. These correlations indicate that the performance of wheat hybrids with high GY and earliness could be predicted by determining the GD of the parents by using SSR markers. Multivariate analysis (stepwise regression and path coefficient) suggested that GFD, hundred kernel weight, days to maturity, and number of kernels per spike had the highest influence on GY.


Assuntos
Resposta ao Choque Térmico/genética , Vigor Híbrido/genética , Seleção Genética/genética , Triticum/genética , Pão , Cruzamento , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Genótipo , Humanos , Hibridização Genética/genética , Repetições de Microssatélites/genética , Fenótipo , Triticum/crescimento & desenvolvimento
18.
Plant Cell ; 32(10): 3041-3042, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32732311
19.
PLoS One ; 15(8): e0237173, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32845897

RESUMO

Gentian is an important ornamental flower in Japan. The corolla of the majority of cultivated Japanese gentians have green spots, which are rarely encountered in flowers of other angiosperms. Little information is available on the functional traits of the green spots. In this study, we characterized the green spots in the Japanese gentian corolla using a number of microscopic techniques. Opto-digital microscopy revealed that a single visible green spot is composed of approximately 100 epidermal cells. The epidermal cells of a green spot formed a dome-like structure and the cell lumen contained many green structures that were granular and approximately 5 µm in diameter. The green structures emitted red autofluorescence when irradiated with 488 nm excitation light. Transmission electron microscopy revealed that the green structures contained typical thylakoids and grana, thus indicating they are chloroplasts. No grana were observed and the thylakoids had collapsed in the plastids of epidermal cells surrounding green spots. To estimate the rate of photosynthetic electron transfer of the green spots, we measured chlorophyll fluorescence using the MICROSCOPY version of an Imaging-PAM (pulse-amplitude-modulated) fluorometer. Under actinic light of 449 µmol m-2 s-1, substantial electron flow through photosystem II was observed. Observation of green spot formation during corolla development revealed that immature green spots formed at an early bud stage and developed to maturity associated with chloroplast degradation in the surrounding epidermal cells. These results confirmed that the Japanese gentian corolla contains functional chloroplasts in restricted areas of epidermal cells and indicated that a sophisticated program for differential regulation of chloroplast formation and degradation is operative in the epidermis.


Assuntos
Flores/citologia , Flores/metabolismo , Gentiana/anatomia & histologia , Tilacoides/metabolismo , Clorofila/metabolismo , Transporte de Elétrons , Japão , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Fotossíntese , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Epiderme Vegetal/citologia , Epiderme Vegetal/metabolismo , Folhas de Planta/metabolismo
20.
Mol Genet Genomics ; 295(6): 1459-1476, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32683543

RESUMO

Polyploidy promotes morphological, physiological, and reproductive diversity in plants. The imminent effect of chromosome doubling in plants is the enlargement of organs such as flowers and fruits, which increases the commercial value of crops. Flowering plays a vital role in the growth and development of angiosperms. Here, we prepared an isolated microspore culture of 'FT', a doubled haploid (DH) line of Chinese cabbage (Brassica rapa L. ssp. pekinensis), and obtained diploid and autotetraploid plants with the same genetic background. Compared with diploids, the autotetraploids were characterized by large floral organs, dark petals, delayed flowering, and reduced fertility. The indole-3-acetic acid (IAA) and jasmonic acid (JA) levels in autotetraploid petals were significantly higher and the abscisic acid (ABA) level was significantly lower than those in the diploid petals. The lutein level in autotetraploid petals was nearly two times higher than that in the diploid petals. A comparative transcriptome analysis revealed 14,412 differentially expressed genes (DEGs) between the diploids and autotetraploids, and they were enriched in 117 Gene Ontology terms and 110 Kyoto Encyclopedia of Genes and Genomes pathways. We detected 231 DEGs related to phytohormone signal transduction and 29 DEGs involved in carotenoid biosynthesis. An miRNA-target mRNA analysis showed that 32 DEGs regulated by 16 DEMs were associated with flowering timing (BraA03000336, BraA09004319, and BraA09000515), petal development (BraA05002408, BraA01004006, BraA09004069, and BraA04000966), flower opening (BraA07000350), and pollen development (BraA01000720, BraA09005727, and BraA01000253). This study provides information to help elucidate the molecular mechanisms underlying phenotypic variations induced by autopolyploidy in Chinese cabbage.


Assuntos
Brassica rapa/genética , Diploide , Flores/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Pequeno RNA não Traduzido/genética , Tetraploidia , Brassica rapa/crescimento & desenvolvimento , Flores/classificação , Flores/crescimento & desenvolvimento , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/genética , RNA-Seq , Transcriptoma
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