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1.
Sci Rep ; 11(1): 9398, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33931706

RESUMO

Although spikelet-related traits such as size of anther, spikelet, style, and stigma are associated with sexual reproduction in grasses, no QTLs have been reported in sorghum. Additionally, there are only a few reports on sorghum QTLs related to grain size, such as grain length, width, and thickness. In this study, we performed QTL analyses of nine spikelet-related traits (length of sessile spikelet, pedicellate spikelet, pedicel, anther, style, and stigma; width of sessile spikelet and stigma; and stigma pigmentation) and six grain-related traits (length, width, thickness, length/width ratio, length/thickness ratio, and width/thickness ratio) using sorghum recombinant inbred lines. We identified 36 and 7 QTLs for spikelet-related traits and grain-related traits, respectively, and found that most sorghum spikelet organ length- and width-related traits were partially controlled by the dwarf genes Dw1 and Dw3. Conversely, we found that these Dw genes were not strongly involved in the regulation of grain size. The QTLs identified in this study aid in understanding the genetic basis of spikelet- and grain-related traits in sorghum.


Assuntos
Grão Comestível/crescimento & desenvolvimento , Locos de Características Quantitativas , Sorghum/genética , Grão Comestível/genética , Topos Floridos/genética , Topos Floridos/crescimento & desenvolvimento , Sorghum/crescimento & desenvolvimento
2.
Mol Genet Genomics ; 296(4): 877-891, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33903955

RESUMO

In a rapidly changing climate, flowering time (FL) adaptation is important to maximize seed yield in flax (Linum usitatissimum L.). However, our understanding of the genetic mechanism underlying FL in this multipurpose crop remains limited. With the aim of dissecting the genetic architecture of FL in flax, a genome-wide association study (GWAS) was performed on 200 accessions of the flax core collection evaluated in four environments. Two single-locus and six multi-locus models were applied using 70,935 curated single nucleotide polymorphism (SNP) markers. A total of 40 quantitative trait nucleotides (QTNs) associated with 27 quantitative trait loci (QTL) were identified in at least two environments. The number of QTL with positive-effect alleles in accessions was significantly correlated with FL (r = 0.77 to 0.82), indicating principally additive gene actions. Nine QTL were significant in at least three of the four environments accounting for 3.06-14.71% of FL variation. These stable QTL spanned regions that harbored 27 Arabidopsis thaliana and Oryza sativa FL-related orthologous genes including FLOWERING LOCUS T (Lus10013532), FLOWERING LOCUS D (Lus10028817), transcriptional regulator SUPERMAN (Lus10021215), and gibberellin 2-beta-dioxygenase 2 (Lus10037816). In silico gene expression analysis of the 27 FL candidate gene orthologous suggested that they might play roles in the transition from vegetative to reproductive phase, flower development and fertilization. Our results provide new insights into the QTL architecture of flowering time in flax, identify potential candidate genes for further studies, and demonstrate the effectiveness of combining different GWAS models for the genetic dissection of complex traits.


Assuntos
Linho , Topos Floridos/crescimento & desenvolvimento , Topos Floridos/genética , Linho/genética , Linho/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Loci Gênicos/genética , Estudo de Associação Genômica Ampla/métodos , Desequilíbrio de Ligação , Locos de Características Quantitativas , Sementes/genética , Análise de Sequência de DNA , Fatores de Tempo
3.
Sci Rep ; 10(1): 15155, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32939023

RESUMO

High temperatures have significant impacts on heat-tolerant bolting in lettuce. In this study, it was found that high temperatures could facilitate the accumulation of GA in lettuce to induce bolting, with higher expression levels of two heat shock protein genes LsHsp70-3701 and LsHsp70-2711. By applying VIGS technology, these two Hsp70 genes were incompletely silenced and plant morphological changes under heat treatment of silenced plants were observed. The results showed that lower expression levels of these two genes could enhance bolting stem length of lettuce under high temperatures, which means these two proteins may play a significant role in heat-induced bolting tolerance. By using the yeast two-hybrid technique, it was found that a calmodulin protein could interact with LsHsp70 proteins in a high-temperature stress cDNA library, which was constructed for lettuce. Also, the Hsp70-calmodulin combination can be obtained at high temperatures. According to these results, it can be speculated that the interaction between Hsp70 and calmodulin could be induced under high temperatures and higher GA contents can be obtained at the same time. This study analyses the regulation of heat tolerance in lettuce and lays a foundation for additional studies of heat resistance in lettuce.


Assuntos
Calmodulina/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Lactuca/crescimento & desenvolvimento , Lactuca/metabolismo , Proteínas de Plantas/metabolismo , Topos Floridos/genética , Topos Floridos/crescimento & desenvolvimento , Topos Floridos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Genes de Plantas , Giberelinas/metabolismo , Proteínas de Choque Térmico HSP70/genética , Resposta ao Choque Térmico/genética , Resposta ao Choque Térmico/fisiologia , Temperatura Alta , Lactuca/genética , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas
4.
Genes (Basel) ; 10(8)2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31394782

RESUMO

Amaryllidaceae alkaloids (AAs) have multiple biological effects, which are of interest to the pharmaceutical industry. To unleash the potential of Amaryllidaceae plants as pharmaceutical crops and as sources of AAs, a thorough understanding of the AA biosynthetic pathway is needed. However, only few enzymes in the pathway are known. Here, we report the transcriptome of AA-producing paperwhites (Narcissus papyraceus Ker Gawl). We present a list of 21 genes putatively encoding enzymes involved in AA biosynthesis. Next, a cDNA library was created from 24 different samples of different parts at various developmental stages of N. papyraceus. The expression of AA biosynthetic genes was analyzed in each sample using RT-qPCR. In addition, the alkaloid content of each sample was analyzed by HPLC. Leaves and flowers were found to have the highest abundance of heterocyclic compounds, whereas the bulb, the lowest. Lycorine was also the predominant AA. The gene expression results were compared with the heterocyclic compound profiles for each sample. In some samples, a positive correlation was observed between the gene expression levels and the amount of compounds accumulated. However, due to a probable transport of enzymes and alkaloids in the plant, a negative correlation was also observed, particularly at stage 2.


Assuntos
Alcaloides de Amaryllidaceae/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Narcissus/genética , Transcriptoma , Topos Floridos/genética , Topos Floridos/crescimento & desenvolvimento , Narcissus/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
Insect Sci ; 26(3): 555-568, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29115041

RESUMO

Interactions between ecological communities of herbivores and microbes are commonly mediated by a shared plant. A tripartite interaction between a pathogenic fungus-host plant-herbivorous insect is an example of such mutual influences. In such a system a fungal pathogen commonly has a negative influence on the morphology and biochemistry of the host plant, with consequences for insect herbivore performance. Here we studied whether the biotrophic fungus Podosphaera ferruginea, attacking the great burnet Sanguisorba officinalis, affects caterpillar performance of the endangered scarce large blue butterfly Phengaris teleius. Our results showed that the pathogenic fungus affected the number and size of inflorescences produced by food-plants and, more importantly, had indirect, plant-mediated effects on the abundance, body mass and immune response of caterpillars. Specifically, we found the relationship between caterpillar abundance and variability in inflorescence size on a plant to be positive among healthy food-plants, and negative among infected food-plants. Caterpillars that fed on healthy food-plants were smaller than those that fed on infected food-plants in one studied season, while there was no such difference in the other season. We observed the relationship between caterpillar immune response and the proportion of infected great burnets within a habitat patch to be positive when caterpillars fed on healthy food-plants, and negative when caterpillars fed on infected food-plants. Our results suggest that this biotrophic fungal infection of the great burnet may impose a significant indirect influence on P. teleius caterpillar performance with potential consequences for the population dynamics and structure of this endangered butterfly.


Assuntos
Ascomicetos/fisiologia , Borboletas/crescimento & desenvolvimento , Herbivoria , Sanguisorba/microbiologia , Animais , Borboletas/imunologia , Espécies em Perigo de Extinção , Topos Floridos/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/imunologia , Densidade Demográfica , Sanguisorba/crescimento & desenvolvimento
6.
Nat Commun ; 8(1): 936, 2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-29038434

RESUMO

The barley inflorescence (spike) comprises a multi-noded central stalk (rachis) with tri-partite clusters of uni-floretted spikelets attached alternately along its length. Relative fertility of lateral spikelets within each cluster leads to spikes with two or six rows of grain, or an intermediate morphology. Understanding the mechanisms controlling this key developmental step could provide novel solutions to enhanced grain yield. Classical genetic studies identified five major SIX-ROWED SPIKE (VRS) genes, with four now known to encode transcription factors. Here we identify and characterise the remaining major VRS gene, VRS3, as encoding a putative Jumonji C-type H3K9me2/me3 demethylase, a regulator of chromatin state. Exploring the expression network modulated by VRS3 reveals specific interactions, both with other VRS genes and genes involved in stress, hormone and sugar metabolism. We show that combining a vrs3 mutant allele with natural six-rowed alleles of VRS1 and VRS5 leads to increased lateral grain size and greater grain uniformity.The VRS genes of barley control the fertility of the lateral spikelets on the barley inflorescence. Here, Bull et al. show that VRS3 encodes a putative Jumonji C-type histone demethylase that regulates expression of other VRS genes, and genes involved in stress, hormone and sugar metabolism.


Assuntos
Topos Floridos/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Hordeum/genética , Histona Desmetilases com o Domínio Jumonji/genética , Metabolismo dos Carboidratos , Fertilidade , Haplótipos , Hordeum/crescimento & desenvolvimento , Hordeum/metabolismo , Mutação , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Sementes/crescimento & desenvolvimento , Seleção Genética , Estresse Fisiológico
7.
J Integr Plant Biol ; 59(9): 693-707, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28843032

RESUMO

Grasses display highly diversified inflorescence architectures that differ in the arrangement of spikelets and flowers and determine cereal yields. However, the molecular basis underlying grass inflorescence morphogenesis remains largely unknown. Here we investigate the role of a functionally diversified SEPALLATA MADS-box transcription factor, OsMADS34, in regulating rice (Oryza sativa L.) inflorescence and spikelet development. Microarray analysis showed that, at the very early stages of inflorescence formation, dysfunction of OsMADS34 caused altered expression of 379 genes that are associated with protein modification and degradation, transcriptional regulation, signaling and metabolism activity. Genetic analysis revealed that OsMADS34 controls different aspects of inflorescence structure, branching and meristem activity synergistically with LAX PANICLE1 (LAX1) and FLORAL ORGAN NUMBER4 (FON4), as evidenced by the enhanced phenotypes of osmads34 lax1 and osmads34 fon4 compared with the single mutants. Additionally, double mutant between osmads34 and the sterile lemma defective mutant elongated empty glume (ele) displayed an enhanced phenotype, that is, longer and wider sterile lemmas that were converted into lemma/palea-like organs, suggesting that ELE and OsMADS34 synergistically control the sterile lemma development. OsMADS34 may act together with OsMADS15 in controlling sterile lemma development. Collectively, these findings provide insights into the regulatory function of OsMADS34 in rice inflorescence and spikelet development.


Assuntos
Topos Floridos/crescimento & desenvolvimento , Proteínas de Domínio MADS/fisiologia , Oryza/fisiologia , Proteínas de Plantas/fisiologia , Topos Floridos/ultraestrutura , Expressão Gênica , Redes Reguladoras de Genes , Oryza/ultraestrutura
8.
J Sci Food Agric ; 97(2): 587-594, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27098241

RESUMO

BACKGROUND: Clonal selection is one of the tools used for grapevine improvement and therefore is very important for obtaining clones with better characteristics than the variety population. The aim of this study was to select superior grapevines of Vitis vinifera L. cv. Muscat Hamburg grown for fresh consumption. RESULTS: The viticultural parameters and fruit composition of 35 selected vines were determined during a 5-year period. The evaluated parameters showed high variability among selected vines. The significant effect of vintage was observed for all descriptors with the exception of the number of seeds per berry and sugar concentration. Additionally, all vines were examined for their tolerance to low temperatures and the results showed 73% and 90% of primary bud injury at -20 and -25 °C, respectively. In relation to berry classification, the percentage of first-class grapes ranged from 60% to 69% for all selected grapevines. Multivariate statistical analysis was performed to classify grapevines based on their performance. CONCLUSION: Fourteen grapevines were identified as the most promising among the 35 vines initially planted, based on high yield, bunch and berry weight, sugar content and percentage of first-grade grapes. Those grapevines were selected for the next phase of the clonal selection. This study highlighted the importance of clonal selection for improvement of the variety population. © 2016 Society of Chemical Industry.


Assuntos
Produção Agrícola , Produtos Agrícolas/química , Carboidratos da Dieta/análise , Qualidade dos Alimentos , Frutas/química , Melhoramento Vegetal , Vitis/química , Aclimatação , Análise por Conglomerados , Temperatura Baixa/efeitos adversos , Produtos Agrícolas/classificação , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Cruzamentos Genéticos , Dissacarídeos/análise , Dissacarídeos/biossíntese , Topos Floridos/classificação , Topos Floridos/crescimento & desenvolvimento , Frutas/classificação , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Humanos , Análise Multivariada , Valor Nutritivo , Epiderme Vegetal/crescimento & desenvolvimento , Caules de Planta/crescimento & desenvolvimento , Análise de Componente Principal , Estações do Ano , Sementes/crescimento & desenvolvimento , Sérvia , Vitis/classificação , Vitis/crescimento & desenvolvimento , Vitis/metabolismo
9.
J Sci Food Agric ; 96(13): 4465-74, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26847375

RESUMO

BACKGROUND: Climate change can affect the productivity and geographic distribution of crops. Therefore, evaluation of adaptive management options is crucial in dealing with negative impacts of climate change. The objectives of this study were to simulate the impacts of climate change on maize production in the north-east of Iran. Moreover, vulnerability index which indicated that how much of the crop yield loss is related to the drought was computed for each location to identify where adaptation and mitigation strategies are effective. Different sowing dates were also applied as an adaptation approach to decrease the negative impacts of climate change in study area. RESULTS: The results showed that the maize yield would decline during the 21st century from -2.6% to -82% at all study locations in comparison with the baseline. The result of vulnerability index also indicated that using the adaptation strategies could be effective in all of the study areas. Using different sowing dates as an adaptation approach showed that delaying the sowing date will be advantageous in order to obtain higher yield in all study locations in future. CONCLUSION: This study provided insight regarding the climate change impacts on maize production and the efficacy of adaptation strategies. © 2016 Society of Chemical Industry.


Assuntos
Adaptação Fisiológica , Mudança Climática , Produção Agrícola , Produtos Agrícolas/fisiologia , Modelos Biológicos , Sementes/fisiologia , Zea mays/fisiologia , Adaptação Fisiológica/efeitos da radiação , Mudança Climática/economia , Simulação por Computador , Produção Agrícola/economia , Produção Agrícola/tendências , Produtos Agrícolas/economia , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/efeitos da radiação , Clima Desértico , Secas/economia , Topos Floridos/crescimento & desenvolvimento , Topos Floridos/fisiologia , Topos Floridos/efeitos da radiação , Abastecimento de Alimentos/economia , Previsões , Humanos , Irã (Geográfico) , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Estações do Ano , Sementes/crescimento & desenvolvimento , Sementes/efeitos da radiação , Luz Solar , Zea mays/crescimento & desenvolvimento , Zea mays/efeitos da radiação
10.
J Sci Food Agric ; 96(13): 4575-83, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26910811

RESUMO

BACKGROUND: Grapevine cluster morphology influences the quality and commercial value of wine and table grapes. It is routinely evaluated by subjective and inaccurate methods that do not meet the requirements set by the food industry. Novel two-dimensional (2D) and three-dimensional (3D) machine vision technologies emerge as promising tools for its automatic and fast evaluation. RESULTS: The automatic evaluation of cluster length, width and elongation was successfully achieved by the analysis of 2D images, significant and strong correlations with the manual methods being found (r = 0.959, 0.861 and 0.852, respectively). The classification of clusters according to their shape can be achieved by evaluating their conicity in different sections of the cluster. The geometric reconstruction of the morphological volume of the cluster from 2D features worked better than the direct 3D laser scanning system, showing a high correlation (r = 0.956) with the manual approach (water displacement method). In addition, we constructed and validated a simple linear regression model for cluster compactness estimation. It showed a high predictive capacity for both the training and validation subsets of clusters (R(2) = 84.5 and 71.1%, respectively). CONCLUSION: The methodologies proposed in this work provide continuous and accurate data for the fast and objective characterisation of cluster morphology. © 2016 Society of Chemical Industry.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Inspeção de Alimentos/métodos , Qualidade dos Alimentos , Frutas/crescimento & desenvolvimento , Caules de Planta/crescimento & desenvolvimento , Vitis/crescimento & desenvolvimento , Algoritmos , Inteligência Artificial , Produtos Agrícolas/classificação , Topos Floridos/classificação , Topos Floridos/crescimento & desenvolvimento , Frutas/classificação , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Modelos Lineares , Fotografação , Caules de Planta/classificação , Espanha , Especificidade da Espécie , Vitis/classificação
11.
Plant Physiol ; 169(2): 1179-91, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26243616

RESUMO

Panicle development, a key event in rice (Oryza sativa) reproduction and a critical determinant of grain yield, forms a branched structure containing multiple spikelets. Genetic and environmental factors can perturb panicle development, causing panicles to degenerate and producing characteristic whitish, small spikelets with severely reduced fertility and yield; however, little is known about the molecular basis of the formation of degenerating panicles in rice. Here, we report the identification and characterization of the rice panicle degenerative mutant tutou1 (tut1), which shows severe defects in panicle development. The tut1 also shows a pleiotropic phenotype, characterized by short roots, reduced plant height, and abnormal development of anthers and pollen grains. Molecular genetic studies revealed that TUT1 encodes a suppressor of cAMP receptor/Wiskott-Aldrich syndrome protein family verprolin-homologous (SCAR/WAVE)-like protein. We found that TUT1 contains conserved functional domains found in eukaryotic SCAR/WAVE proteins, and was able to activate Actin-related protein2/3 to promote actin nucleation and polymerization in vitro. Consistently, tut1 mutants show defects in the arrangement of actin filaments in trichome. These results indicate that TUT1 is a functional SCAR/WAVE protein and plays an important role in panicle development.


Assuntos
Actinas/metabolismo , Topos Floridos/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Proteínas de Arabidopsis/genética , Clonagem Molecular , Topos Floridos/fisiologia , Flores/citologia , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Mutação , Oryza/fisiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Pólen/citologia , Pólen/genética , Pólen/crescimento & desenvolvimento , Receptores de AMP Cíclico/genética , Receptores de AMP Cíclico/metabolismo
12.
Indian J Exp Biol ; 52(4): 344-51, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24772937

RESUMO

Four ecotypes of A. thaliana (L.) (Ct-1, Pf-0, Old-1 and Per-i) from low to high latitudes were grown under different light (300 micro mol photon m-2s-1 and 150 micromol photon m-2s') and temperature (22 and 14 degreesC) conditions to investigate their effects on phenotypic plasticity and ecotypic variations in plant growth and first flowering time. The results suggest that in A. thaliana low temperature decreases both phenotypic plasticity and ecotypic variations in first flowering time and total dry matter at final harvest under different light intensities. Relative growth rate is the most stable parameter of A. thaliana that is hardly affected by ecotype (no effect), light (no effect) or temperature (small effect) and this may one of the reason why A. thaliana is widely distributed on earth as a result of adaptations to different environments.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Topos Floridos/crescimento & desenvolvimento , Luz , Temperatura , Ecossistema , Fenótipo , Fatores de Tempo
13.
PLoS One ; 9(4): e94171, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24718312

RESUMO

The phase transition from vegetative to reproductive growth is a critical event in the life cycle of flowering plants. FLOWERING LOCUS T (FT) plays a central role in the regulation of this transition by integrating signals from multiple flowering pathways in the leaves and transmitting them to the shoot apical meristem. In this study, we characterized FT homologs in the temperate grasses Brachypodium distachyon and polyploid wheat using transgenic and mutant approaches. Downregulation of FT1 by RNAi was associated with a significant downregulation of the FT-like genes FT2 and FT4 in Brachypodium and FT2 and FT5 in wheat. In a transgenic wheat line carrying a highly-expressed FT1 allele, FT2 and FT3 were upregulated under both long and short days. Overexpression of FT1 caused extremely early flowering during shoot regeneration in both Brachypodium and hexaploid wheat, and resulted in insufficient vegetative tissue to support the production of viable seeds. Downregulation of FT1 transcripts by RNA interference (RNAi) resulted in non-flowering Brachypodium plants and late flowering plants (2-4 weeks delay) in wheat. A similar delay in heading time was observed in tetraploid wheat plants carrying mutations for both FT-A1 and FT-B1. Plants homozygous only for mutations in FT-B1 flowered later than plants homozygous only for mutations in FT-A1, which corresponded with higher transcript levels of FT-B1 relative to FT-A1 in the early stages of development. Taken together, our data indicate that FT1 plays a critical role in the regulation of flowering in Brachypodium and wheat, and that this role is associated with the simultaneous regulation of other FT-like genes. The differential effects of mutations in FT-A1 and FT-B1 on wheat heading time suggest that different allelic combinations of FT1 homoeologs could be used to adjust wheat heading time to improve adaptation to changing environments.


Assuntos
Brachypodium/genética , Genes de Plantas , Triticum/genética , Brachypodium/crescimento & desenvolvimento , Códon/genética , Análise Mutacional de DNA , DNA Complementar/genética , Topos Floridos/genética , Topos Floridos/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genótipo , Família Multigênica/genética , Mutação , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Ploidias , Pólen , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA de Plantas/biossíntese , RNA de Plantas/genética , Transdução de Sinais , Especificidade da Espécie , Transcrição Gênica , Triticum/crescimento & desenvolvimento
14.
Plant J ; 77(4): 616-26, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24330191

RESUMO

The awn is a long needle-like appendage that, in some grass species, is formed on the lemma that encloses floral organs together with the palea. In rice, most wild species and most strains of Oryza sativa ssp. indica generate an awn, whereas most strains of O. sativa ssp. japonica do not. In japonica, the long-awn characteristic appears to have been lost during domestication and breeding programs. Here, we found that the genes DROOPING LEAF (DL) and OsETTIN2 (OsETT2) are involved in awn development in the awned indica strain Kasalath. Genetic analyses and RNA-silencing experiments indicate that DL and OsETT2 act independently in awn formation, and that either gene alone is not sufficient for awn development. Scanning electron microscopy revealed that the top region of the lemma (a putative awn primordium) is larger in an awned floret than in an awnless floret. OsETT2 is expressed in the awn primordium in the awned indica floret, but not in the awnless japonica floret except in the provascular bundle. DL is expressed underneath the primordium at similar levels in both indica and japonica florets, suggesting non-cell-autonomous action. We hypothesize that loss of expression of OsETT2 in the awn primordium is probably associated with the failure of awn formation in japonica strains.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Oryza/genética , Proteínas de Plantas/genética , Topos Floridos/anatomia & histologia , Topos Floridos/genética , Topos Floridos/crescimento & desenvolvimento , Topos Floridos/metabolismo , Flores/anatomia & histologia , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Meristema/anatomia & histologia , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Mutação , Oryza/anatomia & histologia , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Fenótipo , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Transporte Proteico , Interferência de RNA , RNA Polimerase Dependente de RNA
15.
J Integr Plant Biol ; 55(8): 682-95, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23931744

RESUMO

Phosphatidylserine (PS), a quantitatively minor membrane phospholipid, is involved in many biological processes besides its role in membrane structure. One PS synthesis gene, PHOSPHATIDYLSERINE SYNTHASE1 (PSS1), has been discovered to be required for microspore development in Arabidopsis thaliana L. but how PSS1 affects postembryonic development is still largely unknown. Here, we show that PSS1 is also required for inflorescence meristem and organ development in Arabidopsis. Disruption of PSS1 causes severe dwarfism, smaller lateral organs and reduced size of inflorescence meristem. Morphological and molecular studies suggest that both cell division and cell elongation are affected in the pss1-1 mutant. RNA in situ hybridization and promoter GUS analysis show that expression of both WUSCHEL (WUS) and CLAVATA3 (CLV3) depend on PSS1. Moreover, the defect in meristem maintenance is recovered and the expression of WUS and CLV3 are restored in the pss1-1 clv1-1 double mutant. Both SHOOTSTEMLESS (STM) and BREVIPEDICELLUS (BP) are upregulated, and auxin distribution is disrupted in rosette leaves of pss1-1. However, expression of BP, which is also a regulator of internode development, is lost in the pss1-1 inflorescence stem. Our data suggest that PSS1 plays essential roles in inflorescence meristem maintenance through the WUS-CLV pathway, and in leaf and internode development by differentially regulating the class I KNOX genes.


Assuntos
Arabidopsis/enzimologia , CDPdiacilglicerol-Serina O-Fosfatidiltransferase/metabolismo , Topos Floridos/crescimento & desenvolvimento , Meristema/crescimento & desenvolvimento , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , CDPdiacilglicerol-Serina O-Fosfatidiltransferase/genética , Divisão Celular , Crescimento Celular , Topos Floridos/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Pleiotropia Genética , Proteínas de Homeodomínio/genética , Ácidos Indolacéticos/metabolismo , Meristema/metabolismo , Mutação , Fenótipo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo
16.
J Evol Biol ; 26(5): 993-1002, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23621367

RESUMO

Investment in reproduction and growth represent a classic tradeoff with implication for life history evolution. The local environment can play a major role in the magnitude and evolutionary consequences of such a tradeoff. Here, we examined the investment in reproductive and vegetative tissue in 40 maternal half-sib families from four different populations of the herb Plantago coronopus growing in either a dry or wet greenhouse environment. Plants originated from populations with an annual or a perennial life form, with annuals prevailing in drier habitats with greater seasonal variation in both temperature and precipitation. We found that water availability affected the expression of the tradeoff (both phenotypic and genetic) between reproduction and growth, being most accentuated under dry condition. However, populations responded very differently to water treatments. Plants from annual populations showed a similar response to drought condition with little variation among maternal families, suggesting a history of selection favouring genotypes with high allocation to reproduction when water availability is low. Plants from annual populations also expressed the highest level of plasticity. For the perennial populations, one showed a large variation among maternal families in resource allocation and expressed significant negative genetic correlations between reproductive and vegetative biomass under drought. The other perennial population showed less variation in response to treatment and had trait values similar to those of the annuals, although it was significantly less plastic. We stress the importance of considering intraspecific variation in response to environmental change such as drought, as conspecific plants exhibited very different abilities and strategies to respond to high versus low water availability even among geographically close populations.


Assuntos
Topos Floridos/crescimento & desenvolvimento , Fenótipo , Plantago/crescimento & desenvolvimento , Água/fisiologia , Biomassa , Secas , Meio Ambiente , Plantago/genética , Reprodução
17.
Am J Bot ; 100(4): 647-63, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23482481

RESUMO

PREMISE OF THE STUDY: Investigations of inflorescence architecture offer insight into the evolution of an astounding array of reproductive shoot systems in the angiosperms, as well as the potential to genetically manipulate these branching patterns to improve crop yield and enhance the aesthetics of horticultural species. The diversity of inflorescences in the economically important family Oleaceae was studied from a comparative developmental point of view for the first time, based on species of seven genera (Chionanthus, Fontanesia, Fraxinus, Jasminum, Ligustrum, Olea, Syringa). METHODS: Series of developmental stages of chemically fixed inflorescences were studied with epi-illumination light microscopy. KEY RESULTS: All taxa studied have inflorescences with terminal flowers. The inflorescences are mostly panicles, but in some cases thyrsoids or compound botryoids. Phyllotaxis of the flower-subtending bracts is mostly decussate, rarely tricussate (Fraxinus) or spiral (Jasminum). Accessory flowers or accessory inflorescences, almost unknown in Oleaceae as yet, were found in two genera. In Syringa, common bract-flower primordia are formed by a delay in early bract development compared to flower development. Such a delay is also expressed by the loss of bracts in the distal part of inflorescence branches in Syringa and Chionanthus. CONCLUSIONS: Significant variation in branching pattern and phyllotaxy was observed among the studied species of Oleaceae. The suppression of bracts and formation of accessory flowers were found as special features of inflorescence ontogeny. The occurrence of accessory flowers and accessory partial inflorescences is interesting from the point of view of dense and flower-rich inflorescences in ornamental species.


Assuntos
Topos Floridos/crescimento & desenvolvimento , Oleaceae/crescimento & desenvolvimento , Evolução Biológica , Topos Floridos/anatomia & histologia , Oleaceae/anatomia & histologia
18.
Plant Biotechnol J ; 11(3): 336-43, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23164055

RESUMO

The adoption of hybrid rice caused the second leap in rice yield after the 'green revolution' and contributes substantially to food security of China and the world. However, almost all cytoplasmic male sterile lines (A lines) as females of hybrid rice have a natural deficiency of 'panicle enclosure', which blocks pollination between the A line and the fertility restorer line as the male (R line) of hybrid rice and decreases seed yield. In hybrid rice seed production, exogenous '920' (the active ingredient is gibberellin A3 ) must be applied to eliminate or alleviate panicle enclosure of the A line; however, this not only increases production cost and pollutes the environment, it also decreases seed quality. In this study, we designed a transgenic approach to improve plant height and panicle exsertion of the A line to facilitate hybrid rice production and maintain the semi-dwarf plant type of the hybrid. This approach comprising two components-artificial microRNA (amiRNA) and artificial target mimicry-can manipulate the differential expression of the endogenous Eui1 gene that is associated with rice internode elongation in the A line and the hybrid. amiRNA is a recently developed gene silencing method with high specificity, while target mimicry is a natural mechanism inhibiting the miRNA function that was also recently characterized. This approach provides a paradigm to tune the expression of endogenous genes to achieve the desired phenotype by combining amiRNA and artificial target mimicry technologies.


Assuntos
Topos Floridos/crescimento & desenvolvimento , Hibridização Genética , Oryza/genética , Inativação Gênica , MicroRNAs , Oryza/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/crescimento & desenvolvimento
19.
J Sci Food Agric ; 93(5): 1140-6, 2013 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22936597

RESUMO

BACKGROUND: Demand for broccoli has increased due to its high content of bioactive compounds. However, broccoli is a perishable commodity with a short shelf life mainly due to dehydration, yellowing and losses of bioactive compounds. Thus, efficient treatments to preserve broccoli quality are needed. RESULTS: The effect of heat treatment on senescence and antioxidant compounds evolution during storage at 20 °C was evaluated in organic and conventionally grown broccoli. Senescence evolved quickly as manifested by floral head yellowing, which was higher in conventional than in organic broccolis, but senescence was significantly delayed by heat treatment. All organic acids, including ascorbic acid, were found at higher concentrations in organic than in conventional broccoli at harvest but decreased during storage in all broccolis. Phenolic concentration and antioxidant activity (in both hydrophilic and lipophilic fractions) also decreased during storage, although these decreases were higher in conventional than in organic broccolis, and no differences were found attributable to heat treatment. CONCLUSIONS: Heat treatment was effective in delaying broccoli senescence, manifested by chlorophyll retention. In addition, organic broccoli maintained higher concentrations of bioactive compounds (ascorbic acid and phenolics) and antioxidant potential during storage than conventional broccoli, with higher potential health beneficial effects.


Assuntos
Antioxidantes/análise , Brassica/química , Topos Floridos/química , Conservação de Alimentos/métodos , Qualidade dos Alimentos , Alimentos Orgânicos/análise , Caules de Planta/química , Antioxidantes/química , Antioxidantes/metabolismo , Ácido Ascórbico/análise , Ácido Ascórbico/química , Ácido Ascórbico/metabolismo , Brassica/crescimento & desenvolvimento , Brassica/metabolismo , Clorofila/análise , Clorofila/química , Clorofila/metabolismo , Topos Floridos/crescimento & desenvolvimento , Topos Floridos/metabolismo , Armazenamento de Alimentos , Temperatura Alta , Interações Hidrofóbicas e Hidrofílicas , Malatos/análise , Malatos/química , Malatos/metabolismo , Fenóis/análise , Fenóis/química , Fenóis/metabolismo , Pigmentos Biológicos/análise , Pigmentos Biológicos/química , Pigmentos Biológicos/metabolismo , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Espanha , Tartaratos/análise , Tartaratos/química , Tartaratos/metabolismo , Fatores de Tempo
20.
Artigo em Inglês | MEDLINE | ID: mdl-22934894

RESUMO

The phenological development of cereal crops from emergence through flowering to maturity is largely controlled by temperature, but also affected by day length and potential physiological stresses. Responses may vary between species and varieties. Climate change will affect the timing of cereal crop development, but exact changes will also depend on changes in varieties as affected by plant breeding and variety choices. This study aimed to assess changes in timing of major phenological stages of cereal crops in Northern and Central Europe under climate change. Records on dates of sowing, flowering, and maturity of wheat, oats and maize were collected from field experiments conducted during the period 1985-2009. Data for spring wheat and spring oats covered latitudes from 46 to 64°N, winter wheat from 46 to 61°N, and maize from 47 to 58°N. The number of observations (site-year-variety combinations) varied with phenological phase, but exceeded 2190, 227, 2076 and 1506 for winter wheat, spring wheat, spring oats and maize, respectively. The data were used to fit simple crop development models, assuming that the duration of the period until flowering depends on temperature and day length for wheat and oats, and on temperature for maize, and that the duration of the period from flowering to maturity in all species depends on temperature only. Species-specific base temperatures were used. Sowing date of spring cereals was estimated using a threshold temperature for the mean air temperature during 10 days prior to sowing. The mean estimated temperature thresholds for sowing were 6.1, 7.1 and 10.1°C for oats, wheat and maize, respectively. For spring oats and wheat the temperature threshold increased with latitude. The effective temperature sums required for both flowering and maturity increased with increasing mean annual temperature of the location, indicating that varieties are well adapted to given conditions. The responses of wheat and oats were largest for the period from flowering to maturity. Changes in timing of cereal phenology by 2040 were assessed for two climate model projections according to the observed dependencies on temperature and day length. The results showed advancements of sowing date of spring cereals by 1-3 weeks depending on climate model and region within Europe. The changes were largest in Northern Europe. Timing of flowering and maturity were projected to advance by 1-3 weeks. The changes were largest for grain maize and smallest for winter wheat, and they were generally largest in the western and northern part of the domain. There were considerable differences in predicted timing of sowing, flowering and maturity between the two climate model projections applied.


Assuntos
Agricultura/métodos , Mudança Climática , Produtos Agrícolas/crescimento & desenvolvimento , Grão Comestível/crescimento & desenvolvimento , Agricultura/tendências , Avena/crescimento & desenvolvimento , Europa (Continente) , Topos Floridos/crescimento & desenvolvimento , Previsões/métodos , Germinação , Humanos , Modelos Biológicos , Modelos Estatísticos , Estações do Ano , Sementes/crescimento & desenvolvimento , Análise Espaço-Temporal , Triticum/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento
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