Evaluación productiva, económica y social del agua de riego de durazno (Prunus persica L. Batsch) en Zacatecas (México)

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José Luis Ríos-Flores; Miriam Torres-Moreno; José Ruiz-Torres; Marco Antonio Torres-Moreno; Jesús Enrique Cantú-Brito

2015-01-01

La escasez de agua limita la agricultura, por lo que su uso debe ser más eficiente en la producción de alimentos. El objetivo de este trabajo fue determinar la productividad económica, física y social del agua del cultivo de durazno (Prunus persica L. Batsch), en la región del Distrito de Desarrollo Rural 183 —correspondiente a Fresnillo, Zacatecas— para el ciclo 2012; se desarrollaron modelos matemáticos para estimar la productividad y eficiencia del agua. En Zacatecas se cosecharon 817 ha d...

UTILIZACION DE ISOENZIMAS DE EXTRACTOS DE HOJAS EN LA CARACTERIZACION DE CULTIVARES DE DURAZNERO (Prunus persica (L Batsch THE USE OF ISOZYME LEAF EXTRACTS IN THE CHARACTERIZATION OF PEACH CULTIVARS (Prunus persica L Batsch

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HECTOR ABEL ALTUBE

2001-08-01

Full Text Available La caracterización de cultivares de duraznero (Prunus persica (L Batsch se hace por medio de la descripción de caracteres agronómicos y morfológicos codificados por organizaciones internacionales, los cuales están fuertemente influenciados por el ambiente. Se han buscado métodos alternativos de caracterización y las isoenzimas han sido utilizadas por su independencia de las condiciones del ambiente, además de identificar individuos en etapas tempranas de su desarrollo. El objetivo del presente estudio es caracterizar cultivares de duraznero mediante el análisis isoenzimático de catecol oxidasas, fosfatasas ácidas, esterazas y peroxidazos en extractos de hojas. Los cultivares de duraznero analizados presentaron bajo polimorfismo isoenzimático, las esterazas caracterizaron diez cultivares, las catecol oxidasas un cultivar agrupándose el resto en cinco modelos, las fosfatasas ácidas caracterizaron dos cultivares agrupándose los otros en siete modelos y las peroxidazos formaron tres grupos. Ello puede explicarse ya que el duraznero es una especie autofértil y presenta una base genética muy reducida. Los evidentes límites discriminatorios de este tipo de análisis hacen que su aporte sea sólo complementario a los métodos de los caracteres agronómicos y morfológicos.Characterization of peach cultivars (Prunus persica (L Batsh was made by description of agronomical and morphological characters codified from international organizations, which are strongly affected by environmental conditions. Alternative methods of characterization have been searched, and isoenzymes have been used as independent of environmental conditions in addition to identify some individuals in early stages of development. The goal of this study is the peach cultivars characterization by isoenzymatic analysis of catecol oxidases, acid phosphatases, esterases and peroxidases within the leaf extracts. The peach cultivars analyzed have showed low isoenzymatic

Genome-Wide Analysis Suggests the Relaxed Purifying Selection Affect the Evolution of WOX Genes in Pyrus bretschneideri, Prunus persica, Prunus mume, and Fragaria vesca

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Yunpeng Cao

2017-06-01

Full Text Available WUSCHEL-related homeobox (WOX family is one of the largest group of transcription factors (TFs specifically found in plant kingdom. WOX TFs play an important role in plant development processes and evolutionary novelties. Although the roles of WOXs in Arabidopsis and rice have been well-studied, however, little are known about the relationships among the main clades in the molecular evolution of these genes in Rosaceae. Here, we carried out a genome-wide analysis and identified 14, 10, 10, and 9 of WOX genes from four Rosaceae species (Fragaria vesca, Prunus persica, Prunus mume, and Pyrus bretschneideri, respectively. According to evolutionary analysis, as well as amino acid sequences of their homodomains, these genes were divided into three clades with nine subgroups. Furthermore, due to the conserved structural patterns among these WOX genes, it was proposed that there should exist some highly conserved regions of microsynteny in the four Rosaceae species. Moreover, most of WOX gene pairs were presented with the conserved orientation among syntenic genome regions. In addition, according to substitution models analysis using PMAL software, no significant positive selection was detected, but type I functional divergence was identified among certain amino acids in WOX protein. These results revealed that the relaxed purifying selection might be the main driving force during the evolution of WOX genes in the tested Rosaceae species. Our result will be useful for further precise research on evolution of the WOX genes in family Rosaceae.

DIAGNOSTICS OF VIRUS PHYTOPATHOGENS FRUIT TREE PLUM POX VIRUS, PRUNUS NECROTIC RINGSPOT VIRUS AND PRUNUS DWARF VIRUS BY BIOLOGICAL AND MOLECULAR DIAGNOSTICS

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Július Rozák

2013-02-01

Full Text Available The aim of this study was to determine the incidence of viral phytopathogen Plum pox virus, Prunus necrotic ringspot virus and Prunus dwarf virus in selected localities of Slovakia and diagnose them using a molecular and biological methods. Forty samples of fruit trees of the genus Prunus, twenty samples from intensive plantings and twenty samples from wild subject were analysed. Biological diagnostic by using biological indicators Prunus persica cv. GF 305, Prunus serrulata cv. Schirofugen and molecular diagnostic by mRT-PCR were applied. Five samples with Plum pox virus were infected. The two samples positive for Prunus necrotic ringspot virus and one sample for Prunus dwarf virus were confirmed. The two samples were found to be infected with two viruses Prunus necrotic ringspot virus and Prunus dwarf virus. This work focuses on two techniques, their application to the diagnosis of stone fruit viruses and their routinely used for sanitary and certification programmes.

Genome-wide association links candidate genes to resistance to Plum Pox Virus in apricot (Prunus armeniaca).

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Mariette, Stéphanie; Wong Jun Tai, Fabienne; Roch, Guillaume; Barre, Aurélien; Chague, Aurélie; Decroocq, Stéphane; Groppi, Alexis; Laizet, Yec'han; Lambert, Patrick; Tricon, David; Nikolski, Macha; Audergon, Jean-Marc; Abbott, Albert G; Decroocq, Véronique

2016-01-01

In fruit tree species, many important traits have been characterized genetically by using single-family descent mapping in progenies segregating for the traits. However, most mapped loci have not been sufficiently resolved to the individual genes due to insufficient progeny sizes for high resolution mapping and the previous lack of whole-genome sequence resources of the study species. To address this problem for Plum Pox Virus (PPV) candidate resistance gene identification in Prunus species, we implemented a genome-wide association (GWA) approach in apricot. This study exploited the broad genetic diversity of the apricot (Prunus armeniaca) germplasm containing resistance to PPV, next-generation sequence-based genotyping, and the high-quality peach (Prunus persica) genome reference sequence for single nucleotide polymorphism (SNP) identification. The results of this GWA study validated previously reported PPV resistance quantitative trait loci (QTL) intervals, highlighted other potential resistance loci, and resolved each to a limited set of candidate genes for further study. This work substantiates the association genetics approach for resolution of QTL to candidate genes in apricot and suggests that this approach could simplify identification of other candidate genes for other marked trait intervals in this germplasm. © 2015 INRA, UMR 1332 BFP New Phytologist © 2015 New Phytologist Trust.

Survey of Prunus necrotic ringspot virus in Rose and Its Variability in Rose and Prunus spp.

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Moury, B; Cardin, L; Onesto, J P; Candresse, T; Poupet, A

2001-01-01

ABSTRACT A survey for viruses in rose propagated in Europe resulted in detection of only Prunus necrotic ringspot virus (PNRSV) among seven viruses screened. Four percent of cut-flower roses from different sources were infected with PNRSV. Progression of the disease under greenhouse conditions was very slow, which should make this virus easy to eradicate through sanitary selection. Comparison of the partial coat protein gene sequences for three representative rose isolates indicated that they do not form a distinct phylogenetic group and show close relations to Prunus spp. isolates. However, a comparison of the reactivity of monoclonal antibodies raised against these isolates showed that the most prevalent PNRSV serotype in rose was different from the most prevalent serotype in Prunus spp. All of the 27 rose isolates tested infected P. persica seedlings, whereas three of the four PNRSV isolates tested from Prunus spp. were poorly infectious in Rosa indica plants. These data suggest adaptation of PNRSV isolates from Prunus spp., but not from rose, to their host plants. The test methodologies developed here to evaluate PNRSV pathogenicity in Prunus spp. and rose could also help to screen for resistant genotypes.

Mites fluctuation population on peach tree (Prunus persica (L. Batsch and in associated plants Flutuação populacional de ácaros na cultura do pessegueiro (Prunus persica (L. Batsch e em plantas associadas

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Carla Rosana Eichelberger

2011-09-01

Full Text Available Despite the importance of peach (Prunus persica (L. Batsch in Rio Grande do Sul, little is known about mites fluctuation population considered important to this crop. The objective of this study was to know the population diversity and fluctuation of mite species associated with Premier and Eldorado varieties in Roca Sales and Venâncio Aires counties, Rio Grande do Sul. The study was conducted from July 2008 to June 2009 when 15 plants were randomly chosen in each area. The plants were divided in quadrants and from each one a branch was chosen from which three leaves were removed: one collected in the apical region, another in the medium and the other in the basal region, totalizing 180 leaves/area. Five of the most abundant associated plants were collected monthly in enough amounts for the screening under the stereoscopic microscope during an hour. A total of 1,124 mites were found belonging to 14 families and 28 species. Tetranychus ludeni Zacher, 1913, Panonychus ulmi (Koch, 1836 and Mononychellus planki (McGregor, 1950 were the most abundant phytophagous mites, whereas Typhlodromalus aripo Deleon, 1967 and Phytoseiulus macropilis (Banks, 1904 the most common predatory mites. The period of one hour under stereoscopic microscope was enough to get a representative sample. In both places evaluated the ecologic indices were low, but little higherin Premier (H' 0.56; EqJ: 0.43 when compared to Eldorado (H' 0.53; EqJ 0.40. In Premier constant species were not observed and accessory only Brevipalpus phoenicis (Geijskes, 1939, T. ludeni and T. aripo. Higher abundance was observed in December and January and bigger amount in April. Already in Eldorado, T. ludeni and P. ulmi were constants. Greater abundance was observed in November and December, whereas grater richness in December and January. In both orchards were not found mites in buds. Tetranychus ludeni is the most abundant phytophagous mites with outbreak population in November, December and

Chemical characterization and thermal properties of kernel oils from Tunisian peach and nectarine varieties of Prunus persica

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Chamli, D.; Bootello, M.A.; Bouali, I.; Jouhri, S.; Boukhchina, S.; Martínez-Force, S.

2017-01-01

A comparative study was conducted to determine the fatty acids, triacylglycerol compositions and thermal properties of Tunisian kernel oils from the Prunus persica varieties, peach and nectarine, grown in two areas of Tunisia, Gabes and Morneg. Qualitatively, the fatty acids composition and triacylglycerol species were identical for all samples. Oleic acid (67.7-75.0%) was the main fatty acid, followed by linoleic (15.7-22.1%) and palmitic (5.6-6.3%) acids. The major triacylglycerol species were triolein, OOO (38.4-50.5%), followed by OOL (18.2-23.2%), POO (8.3-9.7%) and OLL (6.3-10.1%). The thermal profiles were highly influenced by the high content of triolein due to the importance of oleic acid in these oils. Moreover, the fatty acids distribution in TAG external positions was determined as corresponding to an α asymmetry coefficient that was between 0.10 and 0.12, indicating a high asymmetry in the distribution of saturated fatty acids in the position sn-1 and sn-3 in the TAG species of all samples. [es

Chemical characterization and thermal properties of kernel oils from Tunisian peach and nectarine varieties of Prunus persica

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D. Chamli

2017-09-01

Full Text Available A comparative study was conducted to determine the fatty acids, triacylglycerol compositions and thermal properties of Tunisian kernel oils from the Prunus persica varieties, peach and nectarine, grown in two areas of Tunisia, Gabes and Morneg. Qualitatively, the fatty acids composition and triacylglycerol species were identical for all samples. Oleic acid (67.7-75.0% was the main fatty acid, followed by linoleic (15.7-22.1% and palmitic (5.6-6.3% acids. The major triacylglycerol species were triolein, OOO (38.4-50.5%, followed by OOL (18.2-23.2%, POO (8.3-9.7% and OLL (6.3-10.1%. The thermal profiles were highly influenced by the high content of triolein due to the importance of oleic acid in these oils. Moreover, the fatty acids distribution in TAG external positions was determined as corresponding to an α asymmetry coefficient that was between 0.10 and 0.12, indicating a high asymmetry in the distribution of saturated fatty acids in the position sn-1 and sn-3 in the TAG species of all samples.

Roles of endoplasmic reticulum stress and unfolded protein response associated genes in seed stratification and bud endodormancy during chilling accumulation in Prunus persica.

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Xi Ling Fu

Full Text Available Dormancy mechanisms in seeds and buds arrest growth until environmental conditions are optimal for development. A genotype-specific period of chilling is usually required to release dormancy, but the underlying molecular mechanisms are still not fully understood. To discover transcriptional pathways associated with dormancy release common to seed stratification and bud endodormancy, we explored the chilling-dependent expression of 11 genes involved in endoplasmic reticulum stress and the unfolded protein response signal pathways. We propose that endoplasmic reticulum stress and the unfolded protein response impact on seed as well as bud germination and development by chilling-dependent mechanisms. The emerging discovery of similarities between seed stratification and bud endodormancy status indicate that these two processes are probably regulated by common endoplasmic reticulum stress and unfolded protein response signalling pathways. Clarification of regulatory pathways common to both seed and bud dormancy may enhance understanding of the mechanisms underlying dormancy and breeding programs may benefit from earlier prediction of chilling requirements for uniform blooming of novel genotypes of deciduous fruit tree species.

CLONING AND SEQUENCING OF PGIP FROM ‘JIN SERIES’ ALMOND (PRUNUS DULCIS

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Yuhu Han

2015-12-01

Full Text Available Specific primers synthesized according to conservative regions of polygalacturonase inhibiting protein (PGIP gene were used to amplify Prunus Dulcis genomic DNA by polymerase-chain reaction (PCR. Six bands (pgip1, pgip2, pgip3, pgip4, pgip5 and pgip6 of genes were obtained and cloned into PBS-T vector. According to the length of bands, 717bp, 864bp, 796bp were A1 (pgip1, pgip2, pgip3, A2 (pgip4, A4 (pgip5, pgip6, respectively. DNA sequences showed that the fragments taken together were the gene encoding PGIP. A2 and A3 contained two exons interrupted by one intron, which has GT-AG sequence. Its DNA and amino acid sequences were highly homologies to those from Prunus Persica; Prunus Salicina; Prunus Americana; Prunus Mume, respectively. A conserved lencinerial fragment exists in the derived protein sequence.

Caracterización de cultivares de duraznero (Prunus persica (L. Batsch. por resistencia a heladas

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Javier Emilio Chaar

2015-07-01

Full Text Available Las heladas primaverales son una de las principales limitantes de la producción de frutales de clima templado. Dentro de una misma especie existe variabilidad en resistencia frente al daño en órganos florales ocasionado por temperaturas bajo cero durante la salida del reposo invernal. En cinco cultivares de duraznero (Prunus persica (L. Batsch. y uno de nectarino se evaluó el daño ocasionado por heladas y se determinaron la fecha de plena floración y la densidad de floración. Adicionalmente se determinó la temperatura letal media (TL50 de las yemas florales en el estado de flor abierta, mediante descensos térmicos controlados en laboratorio. Los cultivares (cv de duraznero Maria Bianca y Summer Pearl presentaron las mayores densidades de flores sanas por cm de ramo, luego de la ocurrencia de temperaturas bajo cero en campo. La resistencia a heladas en campo se relacionó principalmente con la elevada densidad de floración, en combinación, en algunos casos, con floración tardía. La floración tardía por sí sola no resultó una característica de resistencia; por tanto, para la elección de cultivares de duraznero con menor riesgo de daño por temperaturas bajo cero es importante tener en cuenta más de una variable relacionada con los órganos reproductivos

DETERMINATION OF A MATHEMATICAL MODEL TO ESTIMATE THE AREA AND DRY WEIGHT OF THE LEAF LIMBO OF Prunus persica CV. Jarillo DETERMINACIÓN DE UN MODELO MATEMÁTICO PARA LA ESTIMACIÓN DEL ÁREA FOLIAR Y PESO SECO DEL LIMBO DE Prunus persica CV. Jarillo

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Enrique Quevedo García

2012-06-01

Full Text Available Abstract. A study was conducted to determine the variables that estimated the leaf limbo area and the leaf limbo dry weight of peach Prunus persica (L. Batsch cv. Jarillo. Fifty leaves, aged 2.5 months, were selected and measured: leaf limbo length and width, petiole length, leaf length, petiole diameter, leaf limbo fresh weight, petiole fresh weight, leaf fresh weight, leaf limbo dry weight, petiole dry weight, leaf dry weight, length/width limbo, petiole length/limbo length and leaf limbo area. The results allowed to obtain regression equations for estimating the leaf area and the limbo dry weight. Using the lineal models LA = b1 + b2 (LLL x LLW and LA= b1+ b2LLL + b3LLW a leaf area equation was determined. Alternative models to calculate limbo dry weight were evaluated LLDW = -b1+ b2 LLFW and LLDW= - b1 + b2LLL + b3PL. The best equations found with an R2 of 0.99 were LA = 1.572 + 0.65169(LLL x LLW, LA=-23.106+2.8064LLW + 3.6761LLL and LLDW = -0.002+0.401(LLFW.Resumen. Se realizó un estudio para determinar las variables que estimaran el área del limbo foliar y el peso seco del limbo de durazno Prunus persica (L. Batsch cv. Jarillo. Se seleccionaron cincuenta hojas con 2,5 meses de edad, fueron medidos: ancho del limbo, longitud del limbo, longitud del peciolo, longitud hoja, diámetro peciolo, peso fresco del limbo, peso fresco del peciolo, peso fresco de la hoja, peso seco del limbo, peso seco peciolo, peso seco de la hoja, longitud /ancho limbo, longitud del peciolo/longitud del limbo, área foliar del limbo. Los resultados alcanzados permitieron obtener ecuaciones de regresión para estimar el área foliar del limbo y el peso seco del limbo. Se halló una ecuación para la determinación del área foliar del limbo con los modelos lineales LA = b1 + b2 (LLL x LLW y LA= b1 + b2LLL + b3LLW. También se evaluaron modelos alternativas para calcular el peso seco del limbo, LLDW = -b1+ b2LLFW y LLDW= - b1 + b2LLL + b3PL. Las mejores ecuaciones

Improvement of physico-chemical properties and phenolic compounds bioavailability by concentrating dietary fiber of peach (Prunus persica) juice by-product.

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Rodríguez-González, Sarahí; Pérez-Ramírez, Iza F; Castaño-Tostado, Eduardo; Amaya-Llano, Silvia; Rodríguez-García, Mario E; Reynoso-Camacho, Rosalía

2018-06-01

This study aimed to concentrate dietary fiber (DF) from peach (Prunus persica) juice by-product (PJBP), to improve its functional properties, and its polyphenols bioavailability. The dietary fiber concentrates (DFCs) were obtained from PJBP using water/ethanol treatments (100:0, 20:80, 50:50, 80:20, and 0:100, v/v) at 1:5 ratio (wet weight/solvent, w/v) for 5 and 20 min at 21 °C. All treatments concentrated condensed tannins, total and insoluble DF, with the highest content found with 100% H 2 O treatment. The major polyphenols of DFC were 4-O-caffeoylquinic, chlorogenic, and 1,5-di-O-caffeoylquinic acids. Water and oil retention capacity and maximum glucose diffusion rate were improved mainly with 100% H 2 O treatment. Healthy rats were fed with a standard diet supplemented with 8% of PJBP, DFC obtained with 100% H 2 O for 5 min, or DFC obtained with 20% EtOH for 5 min. Gastrointestinal digesta weight and viscosity were increased in animals supplemented with 100% H 2 O DFC. Moreover, the urinary excretion of polyphenol metabolites, mainly glucuronide and sulfate conjugates, was increased with this treatment, indicating a greater bioavailability of PJBP polyphenols, which was associated with an increased dietary fiber porosity. Water treatment could be used to potentiate PJBP functional properties and polyphenols bioavailability. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Molecular cloning, identification, and chromosomal localization of two MADS box genes in peach (Prunus persica).

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Zhang, Lin; Xu, Yong; Ma, Rongcai

2008-06-01

MADS box proteins play an important role in floral development. To find genes involved in the floral transition of Prunus species, cDNAs for two MADS box genes, PpMADS1 and PpMADS10, were cloned using degenerate primers and 5'- and 3'-RACE based on the sequence database of P. persica and P. dulcis. The full length of PpMADS1 cDNA is 1,071 bp containing an open reading frame (ORF) of 717 bp and coding for a polypeptide of 238 amino acid residues. The full length of PpMADS10 cDNA is 937 bp containing an ORF of 633 bp and coding for a polypeptide of 210 amino acid residues. Sequence comparison revealed that PpMADS1 and PpMADS10 were highly homologous to genes AP1 and PI in Arabidopsis, respectively. Phylogenetic analysis indicated that PpMADS1 belongs to the euAP1 clade of class A, and PpMADS10 is a member of GLO/PI clade of class B. RT-PCR analysis showed that PpMADS1 was expressed in sepal, petal, carpel, and fruit, which was slightly different from the expression pattern of AP1; PpMADS10 was expressed in petal and stamen, which shared the same expression pattern as PI. Using selective mapping strategy, PpMADS1 was assigned onto the Bin1:50 on the G1 linkage group between the markers MCO44 and TSA2, and PpMADS10 onto the Bin1:73 on the same linkage group between the markers Lap-1 and FGA8. Our results provided the basis for further dissection of the two MADS box gene function.

Investigation of the aroma of commercial peach (Prunus persica L. Batsch) types by Proton Transfer Reaction-Mass Spectrometry (PTR-MS) and sensory analysis.

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Bianchi, Tiago; Weesepoel, Yannick; Koot, Alex; Iglesias, Ignasi; Eduardo, Iban; Gratacós-Cubarsí, Marta; Guerrero, Luis; Hortós, Maria; van Ruth, Saskia

2017-09-01

The aim of this study was to investigate the aroma and sensory profiles of various types of peaches (Prunus persica L. Batsch.). Forty-three commercial cultivars comprising peaches, flat peaches, nectarines, and canning peaches (pavías) were grown over two consecutive harvest years. Fruits were assessed for chemical aroma and sensory profiles. Chemical aroma profile was obtained by proton transfer reaction-mass spectrometry (PTR-MS) and spectral masses were tentatively identified with PTR-Time of Flight-MS (PTR-Tof-MS). Sensory analysis was performed at commercial maturity considering seven aroma/flavor attributes. The four types of peaches showed both distinct chemical aroma and sensory profiles. Flat peaches and canning peaches showed most distinct patterns according to discriminant analysis. The sensory data were related to the volatile compounds by partial least square regression. γ-Hexalactone, γ-octalactone, hotrienol, acetic acid and ethyl acetate correlated positively, and benzeneacetaldehyde, trimethylbenzene and acetaldehyde negatively to the intensities of aroma and ripe fruit sensory scores. Copyright © 2017 Elsevier Ltd. All rights reserved.

LA RELACIÓN HOJA: FRUTO AFECTA LA PRODUCCIÓN, EL CRECIMIENTO Y LA CALIDAD DEL FRUTO EN DURAZNERO (Prunus persica L. Batsch, cv. ‘Rubidoux’ LEAF TO FRUIT RATIO AFFECTS YIELD, FRUIT GROWTH AND FRUIT QUALITY OF PEACH (Prunus persica L. Batsch, cv. ‘Rubidoux’

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Fánor Casierra-Posada

2007-06-01

Full Text Available El raleo de frutos es un práctica agrícola común en los árboles de melocotón con miras a una cosecha moderada a abundante. Sin embargo, a pesar de las muchas ventajas del raleo, demostradas a lo largo de años de experiencia en la zona templada, esta práctica es a menudo una de las operaciones conducidas de manera ineficiente en el cultivo del duraznero. Árboles de duraznero (Prunus persica L. Batsch cv. ‘Rubidoux’ se ralearon manualmente con el objeto de mejorar la calidad comercial del fruto. Se evaluaron los cambios en el crecimiento del fruto, los sólidos solubles totales, la relación pulpa: semilla, la producción, la calidad del fruto y el diámetro de la fruta, durante una temporada de crecimiento de los frutos según el efecto de la relación hoja: fruto (10; 20; 30; 40 y 50 hojas por fruto, en Guasca - Cundinamarca - Colombia. El raleo se realizó 85 días después de plena floración. Los árboles del tratamiento control no se ralearon. Se observaron diferencias en las curvas de crecimiento del fruto, en el promedio de fruto cosechado, en el peso fresco de los frutos y en su calidad comercial. El contenido de sólidos solubles totales en los frutos y la relación pulpa:semilla aumentaron con el raleo. Al momento de la cosecha, la producción se redujo en los árboles raleados, pero se mejoró la cantidad del fruto comercial. Los tratamientos con 40 y 50 hojas por fruto tuvieron la mayor proporción de frutos de mejor calidad en comparación con los árboles control.Fruit thinning is a standard practice on peach trees carrying a moderate to heavy crop. However, in spite of the many benefits from thinning demostrated through long years of experience in the temperate zone, fruit thinning is too often one of the most unefficiently conducted operations in peach growing. With a view to improve marketable yield and fruit quality, trees of peach (Prunus persica L. Batsch cv. ‘Rubidoux’ were subjected to hand thinning. Changes

Transcriptional mechanisms associated with seed dormancy and dormancy loss in the gibberellin-insensitive sly1-2 mutant of Arabidopsis thaliana

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While widespread transcriptome changes have been previously observed with seed dormancy loss, this study specifically characterized transcriptional changes associated with the increased seed dormancy and dormancy loss of the gibberellin (GA) hormone-insensitive sleepy1-2 (sly1-2) mutant. The SLY1 g...

Self-compatible peach (Prunus persica) has mutant versions of the S haplotypes found in self-incompatible Prunus species.

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Tao, Ryutaro; Watari, Akiko; Hanada, Toshio; Habu, Tsuyoshi; Yaegaki, Hideaki; Yamaguchi, Masami; Yamane, Hisayo

2007-01-01

This study demonstrates that self-compatible (SC) peach has mutant versions of S haplotypes that are present in self-incompatible (SI) Prunus species. All three peach S haplotypes, S (1), S (2), and S (2m), found in this study encode mutated pollen determinants, SFB, while only S (2m) has a mutation that affects the function of the pistil determinant S-RNase. A cysteine residue in the C5 domain of the S (2m)-RNase is substituted by a tyrosine residue, thereby reducing RNase stability. The peach SFB mutations are similar to the SFB mutations found in SC haplotypes of sweet cherry (P. avium) and Japanese apricot (P. mume). SFB (1) of the S (1) haplotype, a mutant version of almond (P. dulcis) S (k) haplotype, encodes truncated SFB due to a 155 bp insertion. SFB (2) of the S (2) and S (2m) haplotypes, both of which are mutant versions of the S (a) haplotype in Japanese plum (P. salicina), encodes a truncated SFB due to a 5 bp insertion. Thus, regardless of the functionality of the pistil determinant, all three peach S haplotypes are SC haplotypes. Our finding that peach has mutant versions of S haplotypes that function in almond and Japanese plum, which are phylogenetically close and remote species, respectively, to peach in the subfamily Prunoideae of the Roasaceae, provides insight into the SC/SI evolution in Prunus. We discuss the significance of SC pollen part mutation in peach with special reference to possible differences in the SI mechanisms between Prunus and Solanaceae.

Effects of different products of peach (Prunus persica L. Batsch) from a variety developed in southern Brazil on oxidative stress and inflammatory parameters in vitro and ex vivo

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Gasparotto, Juciano; Somensi, Nauana; Bortolin, Rafael Calixto; Moresco, Karla Suzana; Girardi, Carolina Saibro; Klafke, Karina; Rabelo, Thallita Kelly; Morrone, Maurilio Da Silva; Vizzotto, Márcia; Raseira, Maria do Carmo Bassols; Moreira, José Claudio Fonseca; Gelain, Daniel Pens

2014-01-01

Antioxidant, anti-glycation and anti-inflammatory activities of fresh and conserved peach fruits (Prunus persica L. Batsch) were compared. Fresh peach pulps, peels, preserve peach pulps and the preserve syrup were prepared at equal concentrations. Rat liver, kidney and brain cortex tissue slices were pre-incubated with peach samples, subjected to oxidative stress with FeSO4 and hydrogen peroxide. Fresh peach pulps and peel conferred higher protection against cytotoxicity and oxidative stress than preserve peach pulps in most tissues. Release of tumor necrosis factor-α and interleukin-1β was also significantly decreased by Fresh peach pulps and peel, followed by preserve peach pulps. Total phenolic determination and HPLC analysis of carotenoids showed that the content of secondary metabolites in Fresh peach pulps and peel is significantly higher than in preserve peach pulps, while the syrup had only small or trace amounts of these compounds. Fresh peach pulps and Peel demonstrated high antioxidant and anti-inflammatory effects preventing against induced damage. PMID:25320458

Evaluation of different doses of gamma radiation on physicochemical characteristics of peach Prunus persica (cv. Chimarrita) minimally processed

International Nuclear Information System (INIS)

Oliveira, Ana Claudia S.; Silva, Lucia C.A.S.; Perecin, Thalita Neme; Arthur, Valter; Harder, Marcia N.C.; Mansi, Debora N.; Canniatti-Brazaca, Solange G.

2009-01-01

The objective was to evaluate the effect of different doses of gamma radiation on the physico-chemical characteristics of peach Prunus persica (cv. Chimarrita) minimally processed, to increase the useful life of the fruit. The peaches were purchased at Ceasa of Campinas/SP and taken to the Laboratory of Radiobiology and Environment of CENA/USP (Piracicaba/SP), which were washed in tap water, peeled and cut into four pieces. The pieces of peach were dipped in sodium hypochlorite solution of 15 mL/L for 4 minutes and dry in a plastic support. Then it were placed in plastic containers (polypropylene). Subsequently, they were irradiated in a Cobalt-60 source, type Gammacell-220 (dose rate of 0,543 kGy/hour) with doses of: 0 (control), 1.0 and 2.0 kGy and stored at a temperature of 8 deg C. The experimental was developed entirely at random with 3 replicates for each treatment. For the statistic analysis was using the Tuckey test at 5% level of probability. Subsequently, analysis was carried out: color factors (l, a, b), pH, soluble solids (deg Brix), acidity and vitamin C. The tests were performed at 1, 3 and 6 days after irradiation. According to the results concluded that the analysis of color and acidity there was no significant difference between treatments, however, for the soluble solids (deg Brix), vitamin C and texture significant difference showing a decrease proportional to increasing doses of radiation and storage time. But the pH increased in relation to dose and during the analysis. (author)

Prunus hybrids rootstocks for flat peach

Directory of Open Access Journals (Sweden)

Pilar Legua

2012-02-01

Full Text Available Peach (Prunus persica L. is the most important stone fruit tree grown in Spain and is the second most important fruit crop in Europe. The influence of eight Prunus rootstocks (GF-677, Krymsk® 86, PADAC 97-36, PADAC 99-05, PADAC 9912-03, PADAC 0024-01, PAC 0021-01 and PAC 0022-01 on vigor, yield and fruit quality traits of 'UFO 3' flat peach cultivar was studied. The highest trunk cross sectional area was exhibited by GF-677 and the lowest by PADAC 99-05, while intermediate values were found on the other rootstocks. The highest yield efficiency was found on PADAC 99-05, PAC 0021-01, PAC 0022-01 and PADAC 0024-01 and the lowest was shown on Krymsk® 86. The fruit quality parameters measured were color, fruit and stone weights, equatorial diameter, pulp thickness, pulp yield, firmness, pH, soluble solids content and titratable acidity. 'UFO 3' grafted on GF-677 resulted in the largest fruit weight, while the smallest was on PADAC 99-05. Fruits of 'UFO 3' showed a tendency to have higher firmness, higher red colored skin and RI when grafted on PADAC 99-05.

Controle da infestação natural de ceratitis capitata (Wied., 1824 (Diptera, Tephritidae em pêssegos(Prunus persica através das radiações gama Control of naturally infested peaches (Prunus persica by mediterranean fruit fly (Ceratitis capitata through the use of gamma radiation

Directory of Open Access Journals (Sweden)

V. Arthur

1993-12-01

Full Text Available Determinou-se a dose desinfestante de radiações gama para pêssegos, Prunus persica, infestados com larvas da mosca do Mediterrâneo, Ceratitis capitata. Utilizaram-se frutas de procedência conhecida no campo fazendo-se uma amostragem prévia, constatando-se que cada fruta continha em média nove larvas do último ínstar da mosca praga. As frutas foram irradiadas em uma fonte de Cobalto-60 com as seguintes doses de radiação gama: 0 (test., 25, 50, 100, 200, 400, 600, 800, 1000 e 1200 Gy, sob uma taxa de 58 Gy por minuto. Após a irradiação as frutas foram colocadas em câmaras climatizadas com a temperatura variando entre 23 e 27°C e a umidade relativa variando entre 65 e 75%. Aguardou-se que as larvas deixassem as frutas e se transformassem em pupas e adultos. A dose letal para larvas, pelos resultados obtidos no experimento, concluiu-se ser de 600 Gy. A dose letal para pupas provenientes de larvas irradiadas dentro das frutas foi de 50 Gy, impedindo totalmente a emergência de adultos.Determination of the dose of gamma radiation to disinfest peaches, Prunus pérsica infested with larvae of Ceratitis capitata (Wied., 1824 was made. Fruits were collected in the field, each one holding about nine larvae of the last instar of the fruit-fly. The fruits were irradiated with Cobalt-60 gamma radiation source at the following doses: 0 (control, 25, 50, 100, 200, 400, 600, 800, 1000 and 1200 Gy; at a dose rate of 58 Gy per minute. After irradiation the fruits were kept in a climatic chamber with the temperature adjusted between 23 and 27°C, and relative humidity between 65 and 75 percent, until the larvae left the fruits and were transformed into pupae and adults. It was concluded that the lethal dose of gamma radiation for larvae at the last instar, in naturally infested peaches, was 600 Gy and the dose of 50 Gy inhibited completely the emergency of adults.

Difference in photosynthetic performance among three peach ...

African Journals Online (AJOL)

The effects of low photosynthetic photon flux density (PPFD) on greenhouse grown peach trees ('Qingfeng': Prunus persica L. Batsch, 'NJN76': Prunus persica L. Batsch and 'Maixiang': P. persica var. nectarine) were investigated. Difference in photosynthesis rate (Pn) and stoma morphology among cultivars were studied.

A fruit quality gene map of Prunus

Directory of Open Access Journals (Sweden)

Bliss Fredrick A

2009-12-01

Full Text Available Abstract Background Prunus fruit development, growth, ripening, and senescence includes major biochemical and sensory changes in texture, color, and flavor. The genetic dissection of these complex processes has important applications in crop improvement, to facilitate maximizing and maintaining stone fruit quality from production and processing through to marketing and consumption. Here we present an integrated fruit quality gene map of Prunus containing 133 genes putatively involved in the determination of fruit texture, pigmentation, flavor, and chilling injury resistance. Results A genetic linkage map of 211 markers was constructed for an intraspecific peach (Prunus persica progeny population, Pop-DG, derived from a canning peach cultivar 'Dr. Davis' and a fresh market cultivar 'Georgia Belle'. The Pop-DG map covered 818 cM of the peach genome and included three morphological markers, 11 ripening candidate genes, 13 cold-responsive genes, 21 novel EST-SSRs from the ChillPeach database, 58 previously reported SSRs, 40 RAFs, 23 SRAPs, 14 IMAs, and 28 accessory markers from candidate gene amplification. The Pop-DG map was co-linear with the Prunus reference T × E map, with 39 SSR markers in common to align the maps. A further 158 markers were bin-mapped to the reference map: 59 ripening candidate genes, 50 cold-responsive genes, and 50 novel EST-SSRs from ChillPeach, with deduced locations in Pop-DG via comparative mapping. Several candidate genes and EST-SSRs co-located with previously reported major trait loci and quantitative trait loci for chilling injury symptoms in Pop-DG. Conclusion The candidate gene approach combined with bin-mapping and availability of a community-recognized reference genetic map provides an efficient means of locating genes of interest in a target genome. We highlight the co-localization of fruit quality candidate genes with previously reported fruit quality QTLs. The fruit quality gene map developed here is a

Authenticity assessment of gamma- and delta-decalactone from prunus fruits by gas chromatography combustion/pyrolysis isotope ratio mass spectrometry (GC-C/P-IRMS).

Science.gov (United States)

Tamura, Hirotoshi; Appel, Markus; Richling, Elke; Schreier, Peter

2005-06-29

Authenticity assessment of gamma-decalactone (1) and delta-decalactone (2) from peach (Prunus persica var. persica), apricot (Prunus armeniaca), and nectarine (Prunus persica var. nectarina) was performed using gas chromatography-isotope ratio mass spectrometry (GC-IRMS) in the combustion (C) and pyrolysis (P) mode. In addition, commercially available synthetic (nature-identical) 1 and 2 as well as biotechnologically produced samples (declared to be "natural") were characterized by their delta(2)H(V)(-)(SMOW) and delta(13)C(V)(-)(PDB) values. For the Prunus fruits under study, rather narrow ranges of delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data of 1, varying from - 34.6 per thousand to - 38.4 per thousand and -160 per thousand to -206 per thousand, respectively, were obtained. Synthetic references of 1 showed delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data ranging from -27.4 per thousand to -28.3 per thousand and -151 per thousand to -184 per thousand, respectively. Samples of 1 declared to be "natural" exhibited ranges from -28.1 per thousand to -29.2 per thousand and -192 per thousand to -286 per thousand for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively. For 2 from peach, apricot, and nectarine, delta(13)C(V)(-)(PDB) values ranging from -34.0 per thousand to -37.9 per thousand were determined; the delta(2)H(V)(-)(SMOW) values ranged from -171 per thousand to -228 per thousand. The delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data for synthetic 2 were -28.2 per thousand and -171 per thousand, respectively, that is, similar to those of 2 from "natural" origin, ranging from -27.7 per thousand to -30.1 per thousand and -185 per thousand to -230 per thousand for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively. GC-C/P-IRMS allowed clear-cut analytical differentiation of the synthetic and "ex-plant" origin of 1 and 2, whereas narrow ranges of delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data were found for samples of

Seed washing, exogenous application of gibberellic acid, and cold stratification enhance the germination of sweet cherry (Prunus avium L.) seed

NARCIS (Netherlands)

Javanmard, T.; Zamani, Z.; Keshavarz Afshar, R.; Hashemi, M.; Struik, P.C.

2014-01-01

Seed germination in sweet cherry (Prunus avium L.) is a slow and lengthy process which has delayed breeding efforts. In this study, seed from ripe fruit of the sweet cherry cultivar ‘Lambert’ were collected and, after removing the endocarp, various dormancy-breaking treatments such as seed washing,

Chemical characterization and thermal properties of kernel oils from Tunisian peach and nectarine varieties of Prunus persica; Caracterización química y propiedades térmicas de los aceites de semillas de variedades tunecinas de melocotón y nectarina de Prunus pérsica

Energy Technology Data Exchange (ETDEWEB)

Chamli, D.; Bootello, M.A.; Bouali, I.; Jouhri, S.; Boukhchina, S.; Martínez-Force, S.

2017-07-01

A comparative study was conducted to determine the fatty acids, triacylglycerol compositions and thermal properties of Tunisian kernel oils from the Prunus persica varieties, peach and nectarine, grown in two areas of Tunisia, Gabes and Morneg. Qualitatively, the fatty acids composition and triacylglycerol species were identical for all samples. Oleic acid (67.7-75.0%) was the main fatty acid, followed by linoleic (15.7-22.1%) and palmitic (5.6-6.3%) acids. The major triacylglycerol species were triolein, OOO (38.4-50.5%), followed by OOL (18.2-23.2%), POO (8.3-9.7%) and OLL (6.3-10.1%). The thermal profiles were highly influenced by the high content of triolein due to the importance of oleic acid in these oils. Moreover, the fatty acids distribution in TAG external positions was determined as corresponding to an α asymmetry coefficient that was between 0.10 and 0.12, indicating a high asymmetry in the distribution of saturated fatty acids in the position sn-1 and sn-3 in the TAG species of all samples. [Spanish] Se ha realizado un estudio comparativo de aceites tunecinos obtenidos a partir de las semillas de variedades de Prunus persica, melocotón y nectarina, cultivadas en dos zonas de Túnez, Gabes y Morneg. Cualitativamente, la composición de ácidos grasos y de especies de triglicéridos fueron idénticas para todas las muestras. El ácido oleico (67,7-75,0%) fue el ácido graso principal, seguido del linoleico (15,7-22,1%) y el palmítico (5,6-6,3%). Las especies principales de triacilglicéridos fueron la trioleina, OOO (38,4-50,5%), seguida de OOL (18,2-23,2%), POO (8,3-9,7%) y OLL (6,3-10,1%). Los perfiles térmicos fueron muy influidos por el alto contenido de trioleina debido a la importancia del ácido oleico en estos aceites. Por otra parte, se determinó la distribución de ácidos grasos en las posiciones externas de los TAG correspondiendo a un coeficiente de asimetría α entre 0,10 y 0,12, lo que indica una alta asimetría en la distribuci

Association studies of dormancy and cooking quality traits in direct ...

Indian Academy of Sciences (India)

Genome-wide scanning, detected a total of seven significant marker-trait associations. (P < 0.01) ... Assam rice; α-amylase; dormancy; cooking quality; association mapping. ...... resource management, association mapping and crop breed- ing.

Comparative effect of Prunus persica L. BATSCH-water extract and tacrine (9-amino-1,2,3,4-tetrahydroacridine hydrochloride) on concentration of extracellular acetylcholine in the rat hippocampus.

Science.gov (United States)

Kim, Yeon-Kye; Koo, Byung-Soo; Gong, Dae-Jong; Lee, Young-Choon; Ko, Jeong-Heon; Kim, Cheorl-Ho

2003-08-01

Prunus persica L. BATSCH seed-water extract (PPE) has been used in the treatment of the degenerative disorders, such as hypermenorrhea and dysmenorrhea, in Taiwan, China, Japan and Korea. In this study, the effects of oral administration of PPE on the extracellular acetylcholine concentration in the hippocampus of rats were evaluated, and compared to that of tacrine (9-amino-1,2,3,4-tetrahydroacridine hydrochloride), a well-known and centrally acting acetylcholinesterase (AChE) inhibitor, which had been developed for the treatment of Alzheimer's disease. We measured the inhibition of brain AChE. PPE at 2.5g/kg and tacrine at 5mg/kg showed significant effects for more than 6h. At these doses, the maximum increases were observed at about 1.5h after administration of PPE, and at about 2h with tacrine, and were 454 and 412% of the pre-level, respectively. The results suggest that oral administration of PPE and tacrine increases acetylcholine concentration in the synaptic cleft of the hippocampus mostly through AChE inhibition, and that PPE has a potent and long-lasting effect on the central cholinergic system.

Elaboración de néctar de durazno (Prunus persica L., endulzado con sucralosa como aprovechamiento de pérdidas poscosecha

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Darío Alberto Pinto Medina

2015-12-01

Full Text Available En el durazno (Prunus persica L, así como en la mayoría de los frutos climatéricos, la calidad y el tiempo de vida útil comercial son afectados por los inadecuados manejos durante la cosecha, transporte y empaque, evidenciados por una serie de daños y defectos que el consumidor rechaza a la hora de adquirir el producto en fresco y que representan cuantiosas pérdidas al final del proceso de mercadeo, esta investigación se basó principalmente en el aprovechamiento de las pérdidas en durazno en el eslabón de la poscosecha, agroindustrializando la materia prima; se realizaron pruebas sensoriales para determinar la variedad más aceptada de tres probadas: Rubidoux, Dorado y Rubidoux-Dorado, no se evidenciaron diferencias significativas entre las muestras. Para darle valor agregado al producto, se fabricó néctar de la variedad Rubidoux endulzado con sucralosa, se realizaron análisis fisicoquímicos, microbiológicos y bromatológicos siguiendo la normatividad vigente. Se encontró que la sucralosa contribuyó a disminuir considerablemente el aporte calórico en el néctar elaborado, pasando de 48 Kcal/100g a 38,69 Kcal/100g. Se concluye que el costo de producción unitario para envase de 350ml ($ 1.054 resulta favorable, puesto que la rentabilidad puede superar el 40%, para un precio de venta de $1.476, generando un producto competitivo en el mercado, dada la calidad y el valor agregado como alimento funcional

Caracterização de três genótipos de umezeiro (Prunus mume Sieb. et Zucc. por marcadores RAPD Characterization of three mume genotypes (Prunus mume Sieb. et Zucc. by RAPD markers

Directory of Open Access Journals (Sweden)

Newton Alex Mayer

2008-12-01

Full Text Available Um projeto de pesquisa visando à utilização de clones de umezeiro (Prunus mume Sieb. et Zucc. como porta-enxertos para pessegueiro [Prunus persica (L. Batsch] está sendo conduzido na FCAV/UNESP, Câmpus de Jaboticabal-SP, com promissoras perspectivas de sucesso. Três genótipos de umezeiro foram selecionados de acordo com características agronômicas desejáveis para esta finalidade. A distinção dos três genótipos entre si, baseada exclusivamente em características morfológicas, apresenta limitações. Dessa forma, o objetivo do presente trabalho foi identificar marcadores RAPD capazes de diferenciar e caracterizar os Clones 05, 15 e a cv. Rigitano (Clone 10 de umezeiro, utilizando-se das cultivares Aurora-1 e Okinawa de pessegueiro como outgroup. Dos 220 primers testados, foram selecionados 42, que amplificaram todos os cinco genótipos. Verificou-se que os marcadores RAPD permitiram a distinção entre o Clone 05, o Clone 15 e a cv. Rigitano de umezeiro, demonstrando a existência de variabilidade genética entre os mesmos. Dentre os três genótipos de umezeiro estudados, constatou-se que a similaridade genética é maior entre o Clone 05 e o Clone 15.A research project with the objective do develop mume clones (Prunus mume Sieb. et Zucc., to be used as rootstocks for peach tree [Prunus persica (L. Batsch] is been carried out at the Faculdade de Ciências Agrárias e Veterinárias (FCAV/UNESP, Jaboticabal Campus, São Paulo State, Brazil. These project showed promising perspectives of success, with three clones that were selected according to their characteristics for peach rootstock. But the distinction of the three clones among them, based only in morphologic characteristics, has presented limitations. The objective of the present research was to identify RAPD markers able to characterize and differentiate the 05 and 15 Clones and Rigitano mume cultivar, using Aurora-1 and Okinawa peach tree as outgroup. Among the 220 tested

Cyanogenic Glucosides and Derivatives in Almond and Sweet Cherry Flower Buds from Dormancy to Flowering

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Jorge Del Cueto

2017-05-01

Full Text Available Almond and sweet cherry are two economically important species of the Prunus genus. They both produce the cyanogenic glucosides prunasin and amygdalin. As part of a two-component defense system, prunasin and amygdalin release toxic hydrogen cyanide upon cell disruption. In this study, we investigated the potential role within prunasin and amygdalin and some of its derivatives in endodormancy release of these two Prunus species. The content of prunasin and of endogenous prunasin turnover products in the course of flower development was examined in five almond cultivars – differing from very early to extra-late in flowering time – and in one sweet early cherry cultivar. In all cultivars, prunasin began to accumulate in the flower buds shortly after dormancy release and the levels dropped again just before flowering time. In almond and sweet cherry, the turnover of prunasin coincided with increased levels of prunasin amide whereas prunasin anitrile pentoside and β-D-glucose-1-benzoate were abundant in almond and cherry flower buds at certain developmental stages. These findings indicate a role for the turnover of cyanogenic glucosides in controlling flower development in Prunus species.

Biology in the Dry Seed: Transcriptome Changes Associated with Dry Seed Dormancy and Dormancy Loss in the Arabidopsis GA-Insensitive sleepy1-2 Mutant

Directory of Open Access Journals (Sweden)

Sven K. Nelson

2017-12-01

Full Text Available Plant embryos can survive years in a desiccated, quiescent state within seeds. In many species, seeds are dormant and unable to germinate at maturity. They acquire the capacity to germinate through a period of dry storage called after-ripening (AR, a biological process that occurs at 5–15% moisture when most metabolic processes cease. Because stored transcripts are among the first proteins translated upon water uptake, they likely impact germination potential. Transcriptome changes associated with the increased seed dormancy of the GA-insensitive sly1-2 mutant, and with dormancy loss through long sly1-2 after-ripening (19 months were characterized in dry seeds. The SLY1 gene was needed for proper down-regulation of translation-associated genes in mature dry seeds, and for AR up-regulation of these genes in germinating seeds. Thus, sly1-2 seed dormancy may result partly from failure to properly regulate protein translation, and partly from observed differences in transcription factor mRNA levels. Two positive regulators of seed dormancy, DELLA GAI (GA-INSENSITIVE and the histone deacetylase HDA6/SIL1 (MODIFIERS OF SILENCING1 were strongly AR-down-regulated. These transcriptional changes appeared to be functionally relevant since loss of GAI function and application of a histone deacetylase inhibitor led to decreased sly1-2 seed dormancy. Thus, after-ripening may increase germination potential over time by reducing dormancy-promoting stored transcript levels. Differences in transcript accumulation with after-ripening correlated to differences in transcript stability, such that stable mRNAs appeared AR-up-regulated, and unstable transcripts AR-down-regulated. Thus, relative transcript levels may change with dry after-ripening partly as a consequence of differences in mRNA turnover.

Discovering genes associated with dormancy in the monogonont rotifer Brachionus plicatilis.

Science.gov (United States)

Denekamp, Nadav Y; Thorne, Michael A S; Clark, Melody S; Kube, Michael; Reinhardt, Richard; Lubzens, Esther

2009-03-13

Microscopic monogonont rotifers, including the euryhaline species Brachionus plicatilis, are typically found in water bodies where environmental factors restrict population growth to short periods lasting days or months. The survival of the population is ensured via the production of resting eggs that show a remarkable tolerance to unfavorable conditions and remain viable for decades. The aim of this study was to generate Expressed Sequence Tags (ESTs) for molecular characterisation of processes associated with the formation of resting eggs, their survival during dormancy and hatching. Four normalized and four subtractive libraries were constructed to provide a resource for rotifer transcriptomics associated with resting-egg formation, storage and hatching. A total of 47,926 sequences were assembled into 18,000 putative transcripts and analyzed using both Blast and GO annotation. About 28-55% (depending on the library) of the clones produced significant matches against the Swissprot and Trembl databases. Genes known to be associated with desiccation tolerance during dormancy in other organisms were identified in the EST libraries. These included genes associated with antioxidant activity, low molecular weight heat shock proteins and Late Embryonic Abundant (LEA) proteins. Real-time PCR confirmed that LEA transcripts, small heat-shock proteins and some antioxidant genes were upregulated in resting eggs, therefore suggesting that desiccation tolerance is a characteristic feature of resting eggs even though they do not necessarily fully desiccate during dormancy. The role of trehalose in resting-egg formation and survival remains unclear since there was no significant difference between resting-egg producing females and amictic females in the expression of the tps-1 gene. In view of the absence of vitellogenin transcripts, matches to lipoprotein lipase proteins suggest that, similar to the situation in dipterans, these proteins may serve as the yolk proteins in

Seed dormancy and germination.

Science.gov (United States)

Penfield, Steven

2017-09-11

Reproduction is a critical time in plant life history. Therefore, genes affecting seed dormancy and germination are among those under strongest selection in natural plant populations. Germination terminates seed dispersal and thus influences the location and timing of plant growth. After seed shedding, germination can be prevented by a property known as seed dormancy. In practise, seeds are rarely either dormant or non-dormant, but seeds whose dormancy-inducing pathways are activated to higher levels will germinate in an ever-narrower range of environments. Thus, measurements of dormancy must always be accompanied by analysis of environmental contexts in which phenotypes or behaviours are described. At its simplest, dormancy can be imposed by the formation of a simple physical barrier around the seed through which gas exchange and the passage of water are prevented. Seeds featuring this so-called 'physical dormancy' often require either scarification or passage through an animal gut (replete with its associated digestive enzymes) to disrupt the barrier and permit germination. In other types of seeds with 'morphological dormancy' the embryo remains under-developed at maturity and a dormant phase exists as the embryo continues its growth post-shedding, eventually breaking through the surrounding tissues. By far, the majority of seeds exhibit 'physiological dormancy' - a quiescence program initiated by either the embryo or the surrounding endosperm tissues. Physiological dormancy uses germination-inhibiting hormones to prevent germination in the absence of the specific environmental triggers that promote germination. During and after germination, early seedling growth is supported by catabolism of stored reserves of protein, oil or starch accumulated during seed maturation. These reserves support cell expansion, chloroplast development and root growth until photoauxotrophic growth can be resumed. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Discovering genes associated with dormancy in the monogonont rotifer Brachionus plicatilis

Directory of Open Access Journals (Sweden)

Kube Michael

2009-03-01

Full Text Available Abstract Background Microscopic monogonont rotifers, including the euryhaline species Brachionus plicatilis, are typically found in water bodies where environmental factors restrict population growth to short periods lasting days or months. The survival of the population is ensured via the production of resting eggs that show a remarkable tolerance to unfavorable conditions and remain viable for decades. The aim of this study was to generate Expressed Sequence Tags (ESTs for molecular characterisation of processes associated with the formation of resting eggs, their survival during dormancy and hatching. Results Four normalized and four subtractive libraries were constructed to provide a resource for rotifer transcriptomics associated with resting-egg formation, storage and hatching. A total of 47,926 sequences were assembled into 18,000 putative transcripts and analyzed using both Blast and GO annotation. About 28–55% (depending on the library of the clones produced significant matches against the Swissprot and Trembl databases. Genes known to be associated with desiccation tolerance during dormancy in other organisms were identified in the EST libraries. These included genes associated with antioxidant activity, low molecular weight heat shock proteins and Late Embryonic Abundant (LEA proteins. Real-time PCR confirmed that LEA transcripts, small heat-shock proteins and some antioxidant genes were upregulated in resting eggs, therefore suggesting that desiccation tolerance is a characteristic feature of resting eggs even though they do not necessarily fully desiccate during dormancy. The role of trehalose in resting-egg formation and survival remains unclear since there was no significant difference between resting-egg producing females and amictic females in the expression of the tps-1 gene. In view of the absence of vitellogenin transcripts, matches to lipoprotein lipase proteins suggest that, similar to the situation in dipterans, these

Amplification of a cytochrome P450 gene is associated with resistance to neonicotinoid insecticides in the aphid Myzus persicae.

Science.gov (United States)

Puinean, Alin M; Foster, Stephen P; Oliphant, Linda; Denholm, Ian; Field, Linda M; Millar, Neil S; Williamson, Martin S; Bass, Chris

2010-06-24

The aphid Myzus persicae is a globally significant crop pest that has evolved high levels of resistance to almost all classes of insecticide. To date, the neonicotinoids, an economically important class of insecticides that target nicotinic acetylcholine receptors (nAChRs), have remained an effective control measure; however, recent reports of resistance in M. persicae represent a threat to the long-term efficacy of this chemical class. In this study, the mechanisms underlying resistance to the neonicotinoid insecticides were investigated using biological, biochemical, and genomic approaches. Bioassays on a resistant M. persicae clone (5191A) suggested that P450-mediated detoxification plays a primary role in resistance, although additional mechanism(s) may also contribute. Microarray analysis, using an array populated with probes corresponding to all known detoxification genes in M. persicae, revealed constitutive over-expression (22-fold) of a single P450 gene (CYP6CY3); and quantitative PCR showed that the over-expression is due, at least in part, to gene amplification. This is the first report of a P450 gene amplification event associated with insecticide resistance in an agriculturally important insect pest. The microarray analysis also showed over-expression of several gene sequences that encode cuticular proteins (2-16-fold), and artificial feeding assays and in vivo penetration assays using radiolabeled insecticide provided direct evidence of a role for reduced cuticular penetration in neonicotinoid resistance. Conversely, receptor radioligand binding studies and nucleotide sequencing of nAChR subunit genes suggest that target-site changes are unlikely to contribute to resistance to neonicotinoid insecticides in M. persicae.

Xylem development in prunus flower buds and the relationship to deep supercooling.

Science.gov (United States)

Ashworth, E N

1984-04-01

Xylem development in eight Prunus species was examined and the relationship to deep supercooling assessed. Dormant buds of six species, P. armeniaca, P. avium, P. cerasus, P. persica, P. salicina, and P. sargentii deep supercooled. Xylem vessel elements were not observed within the dormant floral primordia of these species. Instead, discrete bundles containing procambial cells were observed. Vascular differentiation resumed and xylem continuity was established during the time that the capacity to deep supercool was lost. In P. serotina and P. virginiana, two species which do not supercool, xylem vessels ran the length of the inflorescence and presumably provided a conduit for the spread of ice into the bud. The results support the hypothesis that the lack of xylem continuity is an important feature of buds which deep supercool.

Differentially expressed genes associated with dormancy or germination of Arabidopsis thaliana seeds

NARCIS (Netherlands)

Toorop, P.E.; Barroco, R.M.; Engler, G.; Groot, S.P.C.; Hilhorst, H.W.M.

2005-01-01

Differential display analysis using dormant and non-dormant Arabidopsis thaliana (L.) Heynh seeds resulted in a set of genes that were associated with either dormancy or germination. Expression of the germination-associated genes AtRPL36B and AtRPL27B, encoding two ribosomal proteins, was

Treatment-Induced Autophagy Associated with Tumor Dormancy and Relapse

Science.gov (United States)

2017-07-01

mechanisms make cellular transformation an inevitable event. Harmless somatic mutations have been reported in healthy hematopoietic stem cells of womenwith a...adult stem cells are also in a state of quiescent dormancy until they receive specific signals, such as tissue injury, to exit from dormancy and...lesions. RONS also induce DNA double- strand breaks, which can also be potently mutagenic if not accurately repaired. How- ever, detection of malignant

The contribution of stored malate and citrate to the substrate requirements of metabolism of ripening peach (Prunus persica L. Batsch) flesh is negligible. Implications for the occurrence of phosphoenolpyruvate carboxykinase and gluconeogenesis.

Science.gov (United States)

Famiani, Franco; Farinelli, Daniela; Moscatello, Stefano; Battistelli, Alberto; Leegood, Richard C; Walker, Robert P

2016-04-01

The first aim of this study was to determine the contribution of stored malate and citrate to the substrate requirements of metabolism in the ripening flesh of the peach (Prunus persica L. Batsch) cultivar Adriatica. In the flesh, stored malate accumulated before ripening could contribute little or nothing to the net substrate requirements of metabolism. This was because there was synthesis and not dissimilation of malate throughout ripening. Stored citrate could potentially contribute a very small amount (about 5.8%) of the substrate required by metabolism when the whole ripening period was considered, and a maximum of about 7.5% over the latter part of ripening. The second aim of this study was to investigate why phosphoenolpyruvate carboxykinase (PEPCK) an enzyme utilised in gluconeogenesis from malate and citrate is present in peach flesh. The occurrence and localisation of enzymes utilised in the metabolism of malate, citrate and amino acids were determined in peach flesh throughout its development. Phosphoenolpyruvate carboxylase (essential for the synthesis of malate and citrate) was present in the same cells and at the same time as PEPCK and NADP-malic enzyme (both utilised in the dissimilation of malate and citrate). A hypothesis is presented to explain the presence of these enzymes and to account for the likely occurrence of gluconeogenesis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Selected Plant Metabolites Involved in Oxidation-Reduction Processes during Bud Dormancy and Ontogenetic Development in Sweet Cherry Buds (Prunus avium L.

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Susanne Baldermann

2018-05-01

Full Text Available Many biochemical processes are involved in regulating the consecutive transition of different phases of dormancy in sweet cherry buds. An evaluation based on a metabolic approach has, as yet, only been partly addressed. The aim of this work, therefore, was to determine which plant metabolites could serve as biomarkers for the different transitions in sweet cherry buds. The focus here was on those metabolites involved in oxidation-reduction processes during bud dormancy, as determined by targeted and untargeted mass spectrometry-based methods. The metabolites addressed included phenolic compounds, ascorbate/dehydroascorbate, reducing sugars, carotenoids and chlorophylls. The results demonstrate that the content of phenolic compounds decrease until the end of endodormancy. After a long period of constancy until the end of ecodormancy, a final phase of further decrease followed up to the phenophase open cluster. The main phenolic compounds were caffeoylquinic acids, coumaroylquinic acids and catechins, as well as quercetin and kaempferol derivatives. The data also support the protective role of ascorbate and glutathione in the para- and endodormancy phases. Consistent trends in the content of reducing sugars can be elucidated for the different phenophases of dormancy, too. The untargeted approach with principle component analysis (PCA clearly differentiates the different timings of dormancy giving further valuable information.

Evaluación productiva, económica y social del agua de riego de durazno (Prunus persica L. Batsch en Zacatecas (México

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José Luis Ríos-Flores

2015-01-01

Full Text Available La escasez de agua limita la agricultura, por lo que su uso debe ser más eficiente en la producción de alimentos. El objetivo de este trabajo fue determinar la productividad económica, física y social del agua del cultivo de durazno (Prunus persica L. Batsch, en la región del Distrito de Desarrollo Rural 183 —correspondiente a Fresnillo, Zacatecas— para el ciclo 2012; se desarrollaron modelos matemáticos para estimar la productividad y eficiencia del agua. En Zacatecas se cosecharon 817 ha de durazno; mismas que produjeron 3,954.1 t; con un valor de $32.79 millones de pesos, utilizando un total de 8.17 Mm3 en todo el estado; mientras que en el DDR183-Fresnillo (compuesto por los municipios Fresnillo y Valparaíso se emplearon 3.39 Mm3. La determinación de la huella hídrica azul mostró que, por cada kg de durazno se emplearon 2,066 L en Zacatecas, 2,000 L en Fresnillo, y 1,851 L en Valparaíso. En cuanto al ingreso por metro cúbico, se determinó que en Zacatecas se obtuvo un ingreso de $4.01 m-3, $4.38 m-3 en Fresnillo y $4.83 m-3 en Valparaíso. Mientras, la productividad laboral en Zacatecas fue 97.53 h t-1, en Fresnillo 94.40 h t-1, y en Valparaíso 87.35 h t-1. El trabajador adscrito a la producción de durazno en Zacatecas generó $97.53 h-1, en Fresnillo $94.40 h-1, y $87.35 h-1 en Valparaíso. La producción de durazno en Valparaíso resultó altamente eficiente y productiva, lo que se tradujo en una menor huella hídrica; ello promueve la sustentabilidad del recurso agua en esa región.

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African Journals Online (AJOL)

cadewumi

Materials and Methods: Three fruit extracts Prunus domestica (plum), Prunus persica ... Distilled water was prepared in the Laboratory of Natural Products and ... 80% methanol and water in a ratio of 80:20 respectively; with 0.5ml HCl (5%); for ...

Parasitism rate of Myzus persicae (Sulzer by Diaeretiella rapae (McIntosh in the presence of an alternative, resistant host

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Samira Evangelista Ferreira

Full Text Available ABSTRACT The aphids Lipaphis pseudobrassicae (Davis and Myzus persicae (Sulzer (Hemiptera: Aphididae are important Brassicaceae pests, occurring worldwide and causing significant damage to crops. Interspecific variations in the resistance to natural enemies can potentially impact the interaction among aphid populations. Here we evaluated the hypothesis of associational resistance by determining if the presence of resistant aphids (L. pseudobrassicae reduces the rate of parasitism by Diaeretiella rapae (McIntosh on non-resistant aphids (M. persicae. The experiment was conducted using collard green plants infested with M. persicae and L. pseudobrassicae either resistant or susceptible to D. rapae. The percentage of parasitism by D. rapae was greater on L. pseudobrassicae in the susceptible than in the resistant treatment, but parasitism rates on M. persicae did not differ between the treatments. There was no difference in average growth rate between M. persicae and susceptible L. pseudobrassicae populations, but resistant L. pseudobrassicae had greater growth rate than M. persicae. These results suggest that over a short period of time the presence of resistant L. pseudobrassicae does not affect the rate of parasitism by D. rapae on M. persicae.

Prunus domestica, Prunus persica and Prunus avium extracts ...

African Journals Online (AJOL)

Background: Nowadays antioxidants from plants origin are considered as a promising source of biologically active substances; as synthetic agents are ... suitable for preparing new antioxidant emulsions loaded with pleasant fruity extracts which remain economical, effective and completely safe for human skin therefore, ...

Novel Paraconiothyrium species on stone fruit trees and other woody hosts.

Science.gov (United States)

Damm, U; Verkley, G J M; Crous, P W; Fourie, P H; Haegi, A; Riccioni, L

2008-06-01

Coniothyrium-like fungi are common wood and soil inhabitants and hyperparasites on other fungi. They belong to different fungal genera within the Pleosporales. Several isolates were obtained on wood of different Prunus species (plum, peach and nectarine) from South Africa, on Actinidia species from Italy and on Laurus nobilis from Turkey. Morphological and cultural characteristics as well as DNA sequence data (5.8S nrDNA, ITS1, ITS2, partial SSU nrDNA) were used to characterise them. The isolates belonged to three species of the recently established genus Paraconiothyrium. This is the first report of Paraconiothyrium brasiliense on Prunus spp. from South Africa. Two new species are described, namely Paraconiothyrium variabile sp. nov. on Prunus persica and Prunus salicina from South Africa, on Actinidia spp. from Italy and on Laurus nobilis from Turkey, and Paraconiothyrium africanum sp. nov. on Prunus persica from South Africa. Although other known species of Paraconiothyrium commonly produce aseptate conidia, those of P. africanum and P. hawaiiense comb. nov. are predominantly two-celled.

Control of seed dormancy in Nicotiana plumbaginifolia: post-imbibition abscisic acid synthesis imposes dormancy maintenance.

Science.gov (United States)

Grappin, P; Bouinot, D; Sotta, B; Miginiac, E; Jullien, M

2000-01-01

The physiological characteristics of seed dormancy in Nicotiana plumbaginifolia Viv. are described. The level of seed dormancy is defined by the delay in seed germination (i.e the time required prior to germination) under favourable environmental conditions. A wild-type line shows a clear primary dormancy, which is suppressed by afterripening, whereas an abscisic acid (ABA)-deficient mutant shows a non-dormant phenotype. We have investigated the role of ABA and gibberellic acid (GA(3)) in the control of dormancy maintenance or breakage during imbibition in suitable conditions. It was found that fluridone, a carotenoid biosynthesis inhibitor, is almost as efficient as GA(3) in breaking dormancy. Dry dormant seeds contained more ABA than dry afterripened seeds and, during early imbibition, there was an accumulation of ABA in dormant seeds, but not in afterripened seeds. In addition, fluridone and exogenous GA(3) inhibited the accumulation of ABA in imbibed dormant seeds. This reveals an important role for ABA synthesis in dormancy maintenance in imbibed seeds.

Multiyear evaluation of the durability of the resistance conferred by Ma and RMia genes to Meloidogyne incognita in Prunus under controlled conditions.

Science.gov (United States)

Khallouk, Samira; Voisin, Roger; Portier, Ulysse; Polidori, Joël; Van Ghelder, Cyril; Esmenjaud, Daniel

2013-08-01

Root-knot nematodes (RKNs) (Meloidogyne spp.) are highly polyphagous pests that parasitize Prunus crops in Mediterranean climates. Breeding for RKN-resistant Prunus cultivars, as an alternative to the now-banned use of nematicides, is a real challenge, because the perennial nature of these trees increases the risk of resistance breakdown. The Ma plum resistance (R) gene, with a complete spectrum, and the RMia peach R gene, with a more restricted spectrum, both provide total control of Meloidogyne incognita, the model parthenogenetic species of the genus and the most important RKN in terms of economic losses. We investigated the durability of the resistance to this nematode conferred by these genes, comparing the results obtained with those for the tomato Mi-1 reference gene. In multiyear experiments, we applied a high and continuous nematode inoculum pressure by cultivating nematode-infested susceptible tomato plants with either Prunus accessions carrying Ma or RMia R genes, or with resistant tomato plants carrying the Mi-1 gene. Suitable conditions for Prunus development were achieved by carrying out the studies in a glasshouse, in controlled conditions allowing a short winter leaf fall and dormancy. We first assessed the plum accession 'P.2175', which is heterozygous for the Ma gene, in two successive 2-year evaluations, for resistance to two M. incognita isolates. Whatever the isolate used, no nematodes reproducing on P.2175 were detected, whereas galls and nematodes reproducing on tomato plants carrying Mi-1 were observed. In a second experiment with the most aggressive isolate, interspecific full-sib material (P.2175 × ['Garfi' almond × 'Nemared' peach]), carrying either Ma or RMia (from Nemared) or both (in the heterozygous state) or neither of these genes, was evaluated for 4 years. No virulent nematodes developed on Prunus spp. carrying R genes, whereas galling and virulent individuals were observed on Mi-1-resistant tomato plants. Thus, the resistance to

Map-Based Cloning of Seed Dormancy1-2 Identified a Gibberellin Synthesis Gene Regulating the Development of Endosperm-Imposed Dormancy in Rice.

Science.gov (United States)

Ye, Heng; Feng, Jiuhuan; Zhang, Lihua; Zhang, Jinfeng; Mispan, Muhamad S; Cao, Zhuanqin; Beighley, Donn H; Yang, Jianchang; Gu, Xing-You

2015-11-01

Natural variation in seed dormancy is controlled by multiple genes mapped as quantitative trait loci in major crop or model plants. This research aimed to clone and characterize the Seed Dormancy1-2 (qSD1-2) locus associated with endosperm-imposed dormancy and plant height in rice (Oryza sativa). qSD1-2 was delimited to a 20-kb region, which contains OsGA20ox2 and had an additive effect on germination. Naturally occurring or induced loss-of-function mutations of the gibberellin (GA) synthesis gene enhanced seed dormancy and also reduced plant height. Expression of this gene in seeds (including endospermic cells) during early development increased GA accumulation to promote tissue morphogenesis and maturation programs. The mutant allele prevalent in semidwarf cultivars reduced the seed GA content by up to 2-fold at the early stage, which decelerated tissue morphogenesis including endosperm cell differentiation, delayed abscisic acid accumulation by a shift in the temporal distribution pattern, and postponed dehydration, physiological maturity, and germinability development. As the endosperm of developing seeds dominates the moisture equilibrium and desiccation status of the embryo in cereal crops, qSD1-2 is proposed to control primary dormancy by a GA-regulated dehydration mechanism. Allelic distribution of OsGA20ox2, the rice Green Revolution gene, was associated with the indica and japonica subspeciation. However, this research provided no evidence that the primitive indica- and common japonica-specific alleles at the presumably domestication-related locus functionally differentiate in plant height and seed dormancy. Thus, the evolutionary mechanism of this agriculturally important gene remains open for discussion. © 2015 American Society of Plant Biologists. All Rights Reserved.

Map-Based Cloning of Seed Dormancy1-2 Identified a Gibberellin Synthesis Gene Regulating the Development of Endosperm-Imposed Dormancy in Rice1

Science.gov (United States)

Ye, Heng; Feng, Jiuhuan; Zhang, Lihua; Zhang, Jinfeng; Mispan, Muhamad S.; Cao, Zhuanqin; Beighley, Donn H.; Yang, Jianchang; Gu, Xing-You

2015-01-01

Natural variation in seed dormancy is controlled by multiple genes mapped as quantitative trait loci in major crop or model plants. This research aimed to clone and characterize the Seed Dormancy1-2 (qSD1-2) locus associated with endosperm-imposed dormancy and plant height in rice (Oryza sativa). qSD1-2 was delimited to a 20-kb region, which contains OsGA20ox2 and had an additive effect on germination. Naturally occurring or induced loss-of-function mutations of the gibberellin (GA) synthesis gene enhanced seed dormancy and also reduced plant height. Expression of this gene in seeds (including endospermic cells) during early development increased GA accumulation to promote tissue morphogenesis and maturation programs. The mutant allele prevalent in semidwarf cultivars reduced the seed GA content by up to 2-fold at the early stage, which decelerated tissue morphogenesis including endosperm cell differentiation, delayed abscisic acid accumulation by a shift in the temporal distribution pattern, and postponed dehydration, physiological maturity, and germinability development. As the endosperm of developing seeds dominates the moisture equilibrium and desiccation status of the embryo in cereal crops, qSD1-2 is proposed to control primary dormancy by a GA-regulated dehydration mechanism. Allelic distribution of OsGA20ox2, the rice Green Revolution gene, was associated with the indica and japonica subspeciation. However, this research provided no evidence that the primitive indica- and common japonica-specific alleles at the presumably domestication-related locus functionally differentiate in plant height and seed dormancy. Thus, the evolutionary mechanism of this agriculturally important gene remains open for discussion. PMID:26373662

Arsenic Removal from Aqueous Solutions by Salvadora persica Stem Ash

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Ferdos Kord Mostafapour

2013-01-01

Full Text Available Arsenic is a naturally occurring metalloid, which is widely distributed in nature and is regarded as the largest mass poisoning in history. In the present study, the adsorption potential of Salvadora persica (S. persica stem ash in a batch system for the removal of As(V from aqueous solutions was investigated. Isotherm studies were carried out to evaluate the effect of contact time (20–240 min, pH (2–11, initial arsenic concentration (50–500 μg/L, and adsorbent dose on sorption efficiency. Maximum removal efficiency of 98.33% and 99.32% was obtained at pH 6, adsorbent dosage 3.5 g/L, initial As(V concentration 500 μg/L, and contact time 80 and 60 min for S. persica stem ash at 300 °C and 500 °C, respectively. Also, the adsorption equilibriums were analyzed by the Langmuir and Freundlich isotherm models. Such equilibriums showed that the adsorption data was well fitted with the Freundlich isotherm model for S. persica stem ash at both 300 °C and 500 °C (R2=0.8983 and 0.9274, resp.. According to achieved results, it was defined that S. persica stem ash can be used effectively for As(V removal from the aqueous environment.

Chilling-Mediated DNA Methylation Changes during Dormancy and Its Release Reveal the Importance of Epigenetic Regulation during Winter Dormancy in Apple (Malus x domestica Borkh.).

Science.gov (United States)

Kumar, Gulshan; Rattan, Usha Kumari; Singh, Anil Kumar

2016-01-01

Winter dormancy is a well known mechanism adopted by temperate plants, to mitigate the chilling temperature of winters. However, acquisition of sufficient chilling during winter dormancy ensures the normal phenological traits in subsequent growing period. Thus, low temperature appears to play crucial roles in growth and development of temperate plants. Apple, being an important temperate fruit crop, also requires sufficient chilling to release winter dormancy and normal phenological traits, which are often associated with yield and quality of fruits. DNA cytosine methylation is one of the important epigenetic modifications which remarkably affect the gene expression during various developmental and adaptive processes. In present study, methylation sensitive amplified polymorphism was employed to assess the changes in cytosine methylation during dormancy, active growth and fruit set in apple, under differential chilling conditions. Under high chill conditions, total methylation was decreased from 27.2% in dormant bud to 21.0% in fruit set stage, while no significant reduction was found under low chill conditions. Moreover, the demethylation was found to be decreased, while methylation increased from dormant bud to fruit set stage under low chill as compared to high chill conditions. In addition, RNA-Seq analysis showed high expression of DNA methyltransferases and histone methyltransferases during dormancy and fruit set, and low expression of DNA glcosylases during active growth under low chill conditions, which was in accordance with changes in methylation patterns. The RNA-Seq data of 47 genes associated with MSAP fragments involved in cellular metabolism, stress response, antioxidant system and transcriptional regulation showed correlation between methylation and their expression. Similarly, bisulfite sequencing and qRT-PCR analysis of selected genes also showed correlation between gene body methylation and gene expression. Moreover, significant association

Chilling-Mediated DNA Methylation Changes during Dormancy and Its Release Reveal the Importance of Epigenetic Regulation during Winter Dormancy in Apple (Malus x domestica Borkh..

Directory of Open Access Journals (Sweden)

Gulshan Kumar

Full Text Available Winter dormancy is a well known mechanism adopted by temperate plants, to mitigate the chilling temperature of winters. However, acquisition of sufficient chilling during winter dormancy ensures the normal phenological traits in subsequent growing period. Thus, low temperature appears to play crucial roles in growth and development of temperate plants. Apple, being an important temperate fruit crop, also requires sufficient chilling to release winter dormancy and normal phenological traits, which are often associated with yield and quality of fruits. DNA cytosine methylation is one of the important epigenetic modifications which remarkably affect the gene expression during various developmental and adaptive processes. In present study, methylation sensitive amplified polymorphism was employed to assess the changes in cytosine methylation during dormancy, active growth and fruit set in apple, under differential chilling conditions. Under high chill conditions, total methylation was decreased from 27.2% in dormant bud to 21.0% in fruit set stage, while no significant reduction was found under low chill conditions. Moreover, the demethylation was found to be decreased, while methylation increased from dormant bud to fruit set stage under low chill as compared to high chill conditions. In addition, RNA-Seq analysis showed high expression of DNA methyltransferases and histone methyltransferases during dormancy and fruit set, and low expression of DNA glcosylases during active growth under low chill conditions, which was in accordance with changes in methylation patterns. The RNA-Seq data of 47 genes associated with MSAP fragments involved in cellular metabolism, stress response, antioxidant system and transcriptional regulation showed correlation between methylation and their expression. Similarly, bisulfite sequencing and qRT-PCR analysis of selected genes also showed correlation between gene body methylation and gene expression. Moreover

Mechanisms of Cancer Cell Dormancy--Another Hallmark of Cancer?

Science.gov (United States)

Yeh, Albert C; Ramaswamy, Sridhar

2015-12-01

Disease relapse in cancer patients many years after clinical remission, often referred to as cancer dormancy, is well documented but remains an incompletely understood phenomenon on the biologic level. Recent reviews have summarized potential models that can explain this phenomenon, including angiogenic, immunologic, and cellular dormancy. We focus on mechanisms of cellular dormancy as newer biologic insights have enabled better understanding of this process. We provide a historical context, synthesize current advances in the field, and propose a mechanistic framework that treats cancer cell dormancy as a dynamic cell state conferring a fitness advantage to an evolving malignancy under stress. Cellular dormancy appears to be an active process that can be toggled through a variety of signaling mechanisms that ultimately downregulate the RAS/MAPK and PI(3)K/AKT pathways, an ability that is preserved even in cancers that constitutively depend on these pathways for their growth and survival. Just as unbridled proliferation is a key hallmark of cancer, the ability of cancer cells to become quiescent may be critical to evolving malignancies, with implications for understanding cancer initiation, progression, and treatment resistance. ©2015 American Association for Cancer Research.

Incidence and phylogenetic analyses of Armillaria spp. associated with root disease in peach orchards in the State of Mexico, Mexico

Science.gov (United States)

R. D. Elias-Roman; R. A. Guzman-Plazola; N. B. Klopfenstein; D. Alvarado-Rosales; G. Calderon-Zavala; J. A. Mora-Aguilera; M.-S. Kim; R. Garcia-Espinosa

2013-01-01

Incidence of peach [Prunus persica (L.) Batsch] tree mortality attributed to Armillaria root disease was assessed from 2009 to 2011 in 15 orchards in the State of Mexico, Mexico. Incidence increased gradually every year of assessment, reaching average values of 9.7, 15.3 and 20.3% tree mortality and 23.2, 24.7 and 28.3% disease-impacted area of the orchards during 2009...

Dormancy in Plant Seeds

NARCIS (Netherlands)

Hilhorst, H.W.M.; Finch-Savage, W.E.; Buitink, J.; Bolingue, W.; Leubner-Metzger, G.

2010-01-01

Seed dormancy has been studied intensely over the past decades and, at present, knowledge of this plant trait is at the forefront of plant biology. The main model species is Arabidopsis thaliana, an annual weed, possessing nondeep physiological dormancy. This overview presents the state-of-the-art

Seed after-ripening and dormancy determine adult life history independently of germination timing.

Science.gov (United States)

de Casas, Rafael Rubio; Kovach, Katherine; Dittmar, Emily; Barua, Deepak; Barco, Brenden; Donohue, Kathleen

2012-05-01

• Seed dormancy can affect life history through its effects on germination time. Here, we investigate its influence on life history beyond the timing of germination. • We used the response of Arabidopsis thaliana to chilling at the germination and flowering stages to test the following: how seed dormancy affects germination responses to the environment; whether variation in dormancy affects adult phenology independently of germination time; and whether environmental cues experienced by dormant seeds have an effect on adult life history. • Dormancy conditioned the germination response to low temperatures, such that prolonged periods of chilling induced dormancy in nondormant seeds, but stimulated germination in dormant seeds. The alleviation of dormancy through after-ripening was associated with earlier flowering, independent of germination date. Experimental dormancy manipulations showed that prolonged chilling at the seed stage always induced earlier flowering, regardless of seed dormancy. Surprisingly, this effect of seed chilling on flowering time was observed even when low temperatures did not induce germination. • In summary, seed dormancy influences flowering time and hence life history independent of its effects on germination timing. We conclude that the seed stage has a pronounced effect on life history, the influence of which goes well beyond the timing of germination. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

Dormancy Breaking in Ormosia arborea Seeds

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Edilma Pereira Gonçalves

2011-01-01

Full Text Available Ormosia arborea is a tree species planted in urban areas and used to restore degraded areas. Its seeds are dormant and propagation is difficult. This study compares different dormancy breaking methods and physiological seed quality and seedling production. The seeds were germinated in sand in the laboratory of the Universidade Estadual de Santa Cruz, Ilhéus, Bahia, Brazil. The following dormancy breaking treatments were applied: control (intact seeds, 100°C water immersion; boiling water immersion followed by 24 hours of soaking; scarification with number 100 and number 50 sandpaper opposite from root emergence; sulfuric acid immersion for 1 hour, 50, 45, and 30 minutes. Seed immersion in 100°C and boiling water did not break the dormancy. The study species showed a greater vigor of seedling when its seeds were submitted to treatments associated with tegument rupturing by sandpaper or sulfuric acid. On the other hand, seed scarification with sulfuric acid for 1 hour, 50, 45, and 30 minutes or sandpaper favored seed germination and vigor.

Genetic and Physiological Characterization of Two Clusters of Quantitative Trait Loci Associated With Seed Dormancy and Plant Height in Rice

OpenAIRE

Ye, Heng; Beighley, Donn H.; Feng, Jiuhuan; Gu, Xing-You

2013-01-01

Seed dormancy and plant height have been well-studied in plant genetics, but their relatedness and shared regulatory mechanisms in natural variants remain unclear. The introgression of chromosomal segments from weedy into cultivated rice (Oryza sativa) prompted the detection of two clusters (qSD1-2/qPH1 and qSD7-2/qPH7) of quantitative trait loci both associated with seed dormancy and plant height. Together, these two clusters accounted for >96% of the variances for plant height and ~71% of t...

Performance de deux techniques d'extraction des phénols ...

African Journals Online (AJOL)

Influence in vitro des composes phénoliques des jeunes feuilles du pécher. Prunus persica (1) Batsch, sur le puceron vert du pecher, Myzus persicae sulzer. Agronomie 8 (9) : 787-792. Bell J.N., Dixon R.A., Bailey J.A., Rowell P.M. &. Lamb C.J., 1984. Differential induction of chalcone synthase mRNA activity at the onset.

Using Perls Staining to Trace the Iron Uptake Pathway in Leaves of a Prunus Rootstock Treated with Iron Foliar Fertilizers.

Science.gov (United States)

Rios, Juan J; Carrasco-Gil, Sandra; Abadía, Anunciación; Abadía, Javier

2016-01-01

The aim of this study was to trace the Fe uptake pathway in leaves of Prunus rootstock (GF 677; Prunus dulcis × Prunus persica) plants treated with foliar Fe compounds using the Perls blue method, which detects labile Fe pools. Young expanded leaves of Fe-deficient plants grown in nutrient solution were treated with Fe-compounds using a brush. Iron compounds used were the ferrous salt FeSO4, the ferric salts Fe2(SO4)3 and FeCl3, and the chelate Fe(III)-EDTA, all of them at concentrations of 9 mM Fe. Leaf Fe concentration increases were measured at 30, 60, 90 min, and 24 h, and 70 μm-thick leaf transversal sections were obtained with a vibrating microtome and stained with Perls blue. In vitro results show that the Perls blue method is a good tool to trace the Fe uptake pathway in leaves when using Fe salts, but is not sensitive enough when using synthetic Fe(III)-chelates such as Fe(III)-EDTA and Fe(III)-IDHA. Foliar Fe fertilization increased leaf Fe concentrations with all Fe compounds used, with inorganic Fe salts causing larger leaf Fe concentration increases than Fe(III)-EDTA. Results show that Perls blue stain appeared within 30 min in the stomatal areas, indicating that Fe applied as inorganic salts was taken up rapidly via stomata. In the case of using FeSO4 a progression of the stain was seen with time toward vascular areas in the leaf blade and the central vein, whereas in the case of Fe(III) salts the stain mainly remained in the stomatal areas. Perls stain was never observed in the mesophyll areas, possibly due to the low concentration of labile Fe pools.

Initial characterisation of low and high seed dormancy populations of Lolium rigidum produced by repeated selection.

Science.gov (United States)

Goggin, Danica E; Emery, R J Neil; Powles, Stephen B; Steadman, Kathryn J

2010-10-15

The physiological and biochemical bases of seed dormancy in Lolium rigidum (annual ryegrass) are largely unknown, and study of this process is complicated by the outcrossing nature of the species and the strong influence of environment on seed dormancy. In order to identify heritable biochemical factors contributing to seed dormancy in L. rigidum, seeds from a field-collected population were used to select sub-populations with consistently low or high seed dormancy over four generations. Low-dormancy seeds showed constitutive alpha-amylase activity prior to imbibition, higher concentrations of polyphenols and cis-zeatin, and lower abscisic acid and cis-zeatin riboside concentrations than high-dormancy seeds. Selection for high dormancy was associated with a reduction in response to dark-stratification for 21d at 20 degrees C (an effective means of releasing dormancy in the original, unselected population) over successive generations, but fluridone remained effective in breaking dormancy. Crossing of low- and high-dormancy populations indicated that dormancy level was not dependent upon the maternal genotype of the seed, and that the constitutive alpha-amylase activity and high seed anthocyanin concentrations characteristic of the low-dormancy populations were not correlated to high basal germination ability. Copyright (c) 2010 Elsevier GmbH. All rights reserved.

Seed maturation associated transcriptional programs and regulatory networks underlying genotypic difference in seed dormancy and size/weight in wheat (Triticum aestivum L.).

Science.gov (United States)

Yamasaki, Yuji; Gao, Feng; Jordan, Mark C; Ayele, Belay T

2017-09-16

Maturation forms one of the critical seed developmental phases and it is characterized mainly by programmed cell death, dormancy and desiccation, however, the transcriptional programs and regulatory networks underlying acquisition of dormancy and deposition of storage reserves during the maturation phase of seed development are poorly understood in wheat. The present study performed comparative spatiotemporal transcriptomic analysis of seed maturation in two wheat genotypes with contrasting seed weight/size and dormancy phenotype. The embryo and endosperm tissues of maturing seeds appeared to exhibit genotype-specific temporal shifts in gene expression profile that might contribute to the seed phenotypic variations. Functional annotations of gene clusters suggest that the two tissues exhibit distinct but genotypically overlapping molecular functions. Motif enrichment predicts genotypically distinct abscisic acid (ABA) and gibberellin (GA) regulated transcriptional networks contribute to the contrasting seed weight/size and dormancy phenotypes between the two genotypes. While other ABA responsive element (ABRE) motifs are enriched in both genotypes, the prevalence of G-box-like motif specifically in tissues of the dormant genotype suggests distinct ABA mediated transcriptional mechanisms control the establishment of dormancy during seed maturation. In agreement with this, the bZIP transcription factors that co-express with ABRE enriched embryonic genes differ with genotype. The enrichment of SITEIIATCYTC motif specifically in embryo clusters of maturing seeds irrespective of genotype predicts a tissue specific role for the respective TCP transcription factors with no or minimal contribution to the variations in seed dormancy. The results of this study advance our understanding of the seed maturation associated molecular mechanisms underlying variation in dormancy and weight/size in wheat seeds, which is a critical step towards the designing of molecular strategies

The effectiveness of Penicillium sp. mixed with silica nanoparticles in controlling Myzus persicae

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Hersanti, Hidayat, Syarif; Susanto, Agus; Virgiawan, Regi; Joni, I. Made

2018-02-01

Myzus persicae is one of the major potato plant pests, and also a vector of potato viruses. This pest may cause low quality as well as quantity of potato production. Entomopathogenic fungi can be used to control M. persicae. Penicillium sp. and has been reported as pathogenic to many insect pests. However, it was not that effective in controlling M. persicae. To increase its effectiveness, it can be mixed with plant micro nutrients such as silica, which also protects plants from biotic stress. This experiment was aimed to study the effect of applications of the mixture of Penicillium sp.+ nanosilica in various concentrations on the mortality of M. persicae. There were 8 treatments i.e., applications of single Penicillium sp, single nanosilica 1, 3, and 5 %, and the mixture of Penicillium sp.+ nanosilica 1, 3, and 5 %, and a control (without Penicillium sp.and nanosilica). Each cabbage plant grown in the greenhouse was infested with 20 Penicillium sp. instar II-III, and sprayed according to the treatments. Mortality of M. persicae was assessed after five days of application. The results showed that application of the mixture of Penicillium sp.106spora/ml+nanosilica 5%, and single nanosilica 5% increased the mortality of M. persicae. The mortalities were 37.5%, and 32.5% respectively, compared with 12.5% mortality on the treatment of single Penicillium sp.

Effects of Alchemilla mollis and Alchemilla persica on the wound healing process

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Burçin Ergene Öz

2016-09-01

Full Text Available Alchemilla mollis, is used in traditional medicine for the treatment of wounds and excessive menstruation. Aqueous methanol extracts of A. mollis and A. persica were evaluated for wound healing acivity by using linear incision and circular excision wound models along with hydroxyproline estimation and histopathological analysis. Anti-inflammatory effect was determined according to Whittle method. The extracts prepared from the aerial parts of A. mollis and A. persica exerted significant wound healing activity with the tensile strength values of 39.3% and 33.3%, respectively, and with the contraction values of 51.4% and 43.5%, respectively. Hydroxyproline estimation and histopathological analysis also confirmed the results. The extracts of A. mollis and A. persica showed significant anti-inflammatory activity with the values of 30.6% and 26.6% respectively. These results showed that A. mollis and A. persica possess significant wound healing and anti-inflammatory activities.

Borrelia persica infection in dogs and cats: clinical manifestations, clinicopathological findings and genetic characterization.

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Baneth, Gad; Nachum-Biala, Yaarit; Halperin, Tamar; Hershko, Yizhak; Kleinerman, Gabriela; Anug, Yigal; Abdeen, Ziad; Lavy, Eran; Aroch, Itamar; Straubinger, Reinhard K

2016-05-10

associated with anemia and thrombocytopenia. Fever was more frequently observed in dogs than cats. Domestic canines and felines suffer from clinical disease due to B. persica infection and may also serve as sentinels for human infection.

Comparing the effects of chlorhexidine and persica on alveolar bone healing following tooth extraction in rats, a randomised controlled trial.

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Dorri, Mojtaba; Shahrabi, Shokufeh; Navabazam, Alireza

2012-02-01

Chlorhexidine is broadly prescribed by clinicians for treating extraction socket wounds; however, studies have reported adverse effects for chlorhexidine. Persica, a herbal antibacterial agent, could be an alternative for chlorhexidine. The aim of this randomised controlled trial was to investigate the effects of persica and chlorhexidine on alveolar bone healing following tooth extraction in rats. Eighteen Wistar rats were randomly allocated to three study groups: 0.2% chlorhexidine, 10% persica and controls (tap water). The rats were mouth-rinsed for 14 days. On day 8, the mandibular right first molars of all the rats were extracted. On day 21, the rats were euthanized and histological slides of their extraction sockets were prepared. The amount of new bone formation and the number of inflammatory cells in the extraction socket for each rat were recorded. Data were analysed using linear regression and Mann-Whitney tests. There was no significant difference between the control group and the intervention groups in terms of new bone formation and inflammatory cell count. The mean new bone formation was significantly higher in the persica group than in the chlorhexidine group. There was a significant association between new bone formation and inflammatory cell count in the entire sample. In conclusion, there were no significant differences between rinsing with tap water and rinsing with 0.2% chlorhexidine and 10% persica in enhancing extraction socket wound healing in rats. Extraction socket wound healing in rats was better enhanced with 10% persica than 0.2% chlorhexidine.

Iron Deficiency Prolongs Seed Dormancy in Arabidopsis Plants

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Irene Murgia

2017-12-01

Full Text Available The understanding of seed dormancy, germination and longevity are important goals in plant biology, with relevant applications for agriculture, food industry and also human nutrition. Reactive Oxygen Species (ROS are key molecules involved in the release of dormancy, when their concentrations fall within the so called ‘oxidative window.’ The mechanisms of ROS distribution and sensing in seeds, from dormant to germinating ones, still need elucidation. Also, the impact of iron (Fe deficiency on seed dormancy is still unexplored; this is surprising, given the known pro-oxidant role of Fe when in a free form. We provide evidence of a link between plant Fe nutrition and dormancy of progeny seeds by using different Arabidopsis ecotypes and mutants with different dormancy strengths grown in control soil or under severe Fe deficiency. The latter condition extends the dormancy in several genotypes. The focus on the mechanisms involved in the Fe deficiency-dependent alteration of dormancy and longevity promises to be a key issue in seed (redox biology.

Efeito do comprimento de estacas herbáceas de dois clones de umezeiro (Prunus mume Sieb & Zucc. no enraizamento adventício Effect of the length of herbaceous cuttings of two clones of japanese apricot (Prunus mume Sieb & Zucc. in adventicious rooting

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NEWTON ALEX MAYER

2002-08-01

Full Text Available O umezeiro (Prunus mumeSieb & Zucc. é uma rosácea de folhas caducas, nativa da China, cujos frutos e flores são muito apreciados pelos povos orientais. No Brasil, alguns estudos foram realizados visando a sua utilização como porta-enxerto para pessegueiro e nectarineira, dadas as suas características de adaptação, rusticidade, redução do porte da planta e compatibilidade com algumas cultivares de Prunus persica. O presente estudo foi conduzido em câmara de nebulização sob ripado, pertencente ao Departamento de Produção Vegetal da FCAV/UNESP, Câmpus de Jaboticabal-SP. Objetivou-se verificar a influência de quatro comprimentos de estacas herbáceas no enraizamento de dois clones de umezeiro. O material vegetal, identificado como Clone 10 e Clone 15, foi oriundo do Programa de Melhoramento Genético do Instituto Agronômico de Campinas-SP. O experimento foi constituido de fatorial 2 x 4, em blocos casualizados, sendo o fator clone em 2 níveis (Clone 10 e Clone 15 e o fator comprimento de estaca em 4 níveis (12; 15; 18 e 25cm. Pelos resultados observados, verificou-se diferença entre os clones somente na porcentagem de estacas brotadas e número de raízes por estaca. O comprimento da estaca influenciou na porcentagem de enraizamento e na mortalidade das estacas, sendo que estacas maiores tenderam a apresentar maiores porcentagens de enraizamento e menores de mortalidade. As estacas com 12cm, embora apresentando menor número de raízes por estaca, são recomendadas por permitirem a obtenção de um maior número de estacas por planta-matriz. Houve efeito significativo da interação entre os fatores para número e comprimento de raízes.The japanese apricot (Prunus mume Sieb & Zucc. is a Rosaceae of falling leaves, native of China, whose fruits and flowers are quite appreciated by the oriental people. In Brazil, some studies were accomplished seeking its use as rootstock for peach and nectarine trees, due its adaptation

physiological mechanisms for potato dormancy release

African Journals Online (AJOL)

ACSS

of deep dormancy, during which potato seeds do not germinate after ... dormancy period and sprouting behaviour are major criteria ... develop once sprouting begins; such as changes ...... an example of plant information processing. Plant Cell ...

Cellular Adhesion Promotes Prostate Cancer Cells Escape from Dormancy.

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Ruppender, Nazanin; Larson, Sandy; Lakely, Bryce; Kollath, Lori; Brown, Lisha; Coleman, Ilsa; Coleman, Roger; Nguyen, Holly; Nelson, Peter S; Corey, Eva; Snyder, Linda A; Vessella, Robert L; Morrissey, Colm; Lam, Hung-Ming

2015-01-01

Dissemination of prostate cancer (PCa) cells to the bone marrow is an early event in the disease process. In some patients, disseminated tumor cells (DTC) proliferate to form active metastases after a prolonged period of undetectable disease known as tumor dormancy. Identifying mechanisms of PCa dormancy and reactivation remain a challenge partly due to the lack of in vitro models. Here, we characterized in vitro PCa dormancy-reactivation by inducing cells from three patient-derived xenograft (PDX) lines to proliferate through tumor cell contact with each other and with bone marrow stroma. Proliferating PCa cells demonstrated tumor cell-cell contact and integrin clustering by immunofluorescence. Global gene expression analyses on proliferating cells cultured on bone marrow stroma revealed a downregulation of TGFB2 in all of the three proliferating PCa PDX lines when compared to their non-proliferating counterparts. Furthermore, constitutive activation of myosin light chain kinase (MLCK), a downstream effector of integrin-beta1 and TGF-beta2, in non-proliferating cells promoted cell proliferation. This cell proliferation was associated with an upregulation of CDK6 and a downregulation of E2F4. Taken together, our data provide the first clinically relevant in vitro model to support cellular adhesion and downregulation of TGFB2 as a potential mechanism by which PCa cells may escape from dormancy. Targeting the TGF-beta2-associated mechanism could provide novel opportunities to prevent lethal PCa metastasis.

The genome of Prunus mume.

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Zhang, Qixiang; Chen, Wenbin; Sun, Lidan; Zhao, Fangying; Huang, Bangqing; Yang, Weiru; Tao, Ye; Wang, Jia; Yuan, Zhiqiong; Fan, Guangyi; Xing, Zhen; Han, Changlei; Pan, Huitang; Zhong, Xiao; Shi, Wenfang; Liang, Xinming; Du, Dongliang; Sun, Fengming; Xu, Zongda; Hao, Ruijie; Lv, Tian; Lv, Yingmin; Zheng, Zequn; Sun, Ming; Luo, Le; Cai, Ming; Gao, Yike; Wang, Junyi; Yin, Ye; Xu, Xun; Cheng, Tangren; Wang, Jun

2012-01-01

Prunus mume (mei), which was domesticated in China more than 3,000 years ago as ornamental plant and fruit, is one of the first genomes among Prunus subfamilies of Rosaceae been sequenced. Here, we assemble a 280M genome by combining 101-fold next-generation sequencing and optical mapping data. We further anchor 83.9% of scaffolds to eight chromosomes with genetic map constructed by restriction-site-associated DNA sequencing. Combining P. mume genome with available data, we succeed in reconstructing nine ancestral chromosomes of Rosaceae family, as well as depicting chromosome fusion, fission and duplication history in three major subfamilies. We sequence the transcriptome of various tissues and perform genome-wide analysis to reveal the characteristics of P. mume, including its regulation of early blooming in endodormancy, immune response against bacterial infection and biosynthesis of flower scent. The P. mume genome sequence adds to our understanding of Rosaceae evolution and provides important data for improvement of fruit trees.

Dormancy in breast cancer

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Banys M

2012-12-01

Full Text Available Malgorzata Banys,1,2 Andreas D Hartkopf,1 Natalia Krawczyk,1 Tatjana Kaiser,1 Franziska Meier-Stiegen,1 Tanja Fehm,1 Hans Neubauer11Department of Obstetrics and Gynecology, University of Tuebingen, Tuebingen, Germany; 2Department of Obstetrics and Gynecology, Marienkrankenhaus Hamburg, Hamburg, GermanyAbstract: Tumor dormancy describes a prolonged quiescent state in which tumor cells are present, but disease progression is not yet clinically apparent. Breast cancer is especially known for long asymptomatic periods, up to 25 years, with no evidence of the disease, followed by a relapse. Factors that determine the cell's decision to enter a dormant state and that control its duration remain unclear. In recent years, considerable progress has been made in understanding how tumor cells circulating in the blood interact and extravasate into secondary sites and which factors might determine whether these cells survive, remain dormant, or become macrometastases. The mechanisms of tumor cell dormancy are still not clear. Two different hypotheses are currently discussed: tumor cells persist either by completely withdrawing from the cell cycle or by continuing to proliferate at a slow rate that is counterbalanced by cell death. Because dormant disseminated tumor cells may be the founders of metastasis, one hypothesis is that dormant tumor cells, or at least a fraction of them, share stem cell-like characteristics that may be responsible for their long half-lives and their suggested resistance to standard chemotherapy. Therefore, knowledge of the biology of tumor cell dormancy may be the basis from which to develop innovative targeted therapies to control or eliminate this tumor cell fraction. In this review, we discuss biological mechanisms and clinical implications of tumor dormancy in breast cancer patients.Keywords: tumor dormancy, disseminated tumor cell, circulating tumor cell, targeted therapy

Genomic segments RNA1 and RNA2 of Prunus necrotic ringspot virus codetermine viral pathogenicity to adapt to alternating natural Prunus hosts.

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Cui, Hongguang; Hong, Ni; Wang, Guoping; Wang, Aiming

2013-05-01

Prunus necrotic ringspot virus (PNRSV) affects Prunus fruit production worldwide. To date, numerous PNRSV isolates with diverse pathological properties have been documented. To study the pathogenicity of PNRSV, which directly or indirectly determines the economic losses of infected fruit trees, we have recently sequenced the complete genome of peach isolate Pch12 and cherry isolate Chr3, belonging to the pathogenically aggressive PV32 group and mild PV96 group, respectively. Here, we constructed the Chr3- and Pch12-derived full-length cDNA clones that were infectious in the experimental host cucumber and their respective natural Prunus hosts. Pch12-derived clones induced much more severe symptoms than Chr3 in cucumber, and the pathogenicity discrepancy between Chr3 and Pch12 was associated with virus accumulation. By reassortment of genomic segments, swapping of partial genomic segments, and site-directed mutagenesis, we identified the 3' terminal nucleotide sequence (1C region) in RNA1 and amino acid K at residue 279 in RNA2-encoded P2 as the severe virulence determinants in Pch12. Gain-of-function experiments demonstrated that both the 1C region and K279 of Pch12 were required for severe virulence and high levels of viral accumulation. Our results suggest that PNRSV RNA1 and RNA2 codetermine viral pathogenicity to adapt to alternating natural Prunus hosts, likely through mediating viral accumulation.

Bioactivity-guided fractionation identifies amygdalin as a potent neurotrophic agent from herbal medicine Semen Persicae extract.

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Yang, Chuanbin; Zhao, Jia; Cheng, Yuanyuan; Li, Xuechen; Rong, Jianhui

2014-01-01

Herbal medicine Semen Persicae is widely used to treat blood stasis in Chinese medicine and other oriental folk medicines. Although little is known about the effects of Semen Persicae and its active compounds on neuron differentiation, our pilot study showed that Semen Persicae extract promoted neurite outgrowth in rat dopaminergic PC12 cells. In the present study, we developed a bioactivity-guided fractionation procedure for the characterization of the neurotrophic activity of Semen Persicae extract. The resultant fractions were assayed for neurite outgrowth in PC12 cells based on microscopic assessment. Through liquid-liquid extraction and reverse phase HPLC separation, a botanical glycoside amygdalin was isolated as the active compound responsible for the neurotrophic activity of Semen Persicae extract. Moreover, we found that amygdalin rapidly induced the activation of extracellular-signal-regulated kinase 1/2 (ERK1/2). A specific ERK1/2 inhibitor PD98059 attenuated the stimulatory effect of amygdalin on neurite outgrowth. Taken together, amygdalin was identified as a potent neurotrophic agent from Semen Persicae extract through a bioactivity-guided fractional procedure. The neurotrophic activity of amygdalin may be mediated by the activation of ERK1/2 pathway.

Bioactivity-Guided Fractionation Identifies Amygdalin as a Potent Neurotrophic Agent from Herbal Medicine Semen Persicae Extract

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Chuanbin Yang

2014-01-01

Full Text Available Herbal medicine Semen Persicae is widely used to treat blood stasis in Chinese medicine and other oriental folk medicines. Although little is known about the effects of Semen Persicae and its active compounds on neuron differentiation, our pilot study showed that Semen Persicae extract promoted neurite outgrowth in rat dopaminergic PC12 cells. In the present study, we developed a bioactivity-guided fractionation procedure for the characterization of the neurotrophic activity of Semen Persicae extract. The resultant fractions were assayed for neurite outgrowth in PC12 cells based on microscopic assessment. Through liquid-liquid extraction and reverse phase HPLC separation, a botanical glycoside amygdalin was isolated as the active compound responsible for the neurotrophic activity of Semen Persicae extract. Moreover, we found that amygdalin rapidly induced the activation of extracellular-signal-regulated kinase 1/2 (ERK1/2. A specific ERK1/2 inhibitor PD98059 attenuated the stimulatory effect of amygdalin on neurite outgrowth. Taken together, amygdalin was identified as a potent neurotrophic agent from Semen Persicae extract through a bioactivity-guided fractional procedure. The neurotrophic activity of amygdalin may be mediated by the activation of ERK1/2 pathway.

Antiviral activity of Quercus persica L.: High efficacy and low toxicity

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Ali Karimi

2013-01-01

Full Text Available Background: Drug-resistant strain of Herpes simplex virus type 1 (HSV-I has increased the interest in the use of natural substances. Aims: This study was aimed to determine minimum inhibitory concentration of hydroalchoholic extract of a traditionally used herbal plant, Quercus persica L., on HSV-1 replication on baby hamster kidney (BHK cells. Setting: The study was conducted in Shahrekord University of Medical Sciences, Iran. Design: This was an experimental study. Materials and Methods: BHK cells were grown in monolayer culture with Dulbecco′s modified Eagle′s medium (DMEM supplemented with 5% fetal calf serum and plated onto 48-well culture plates. Fifty percent cytotoxic concentration (CC50% of Q. persica L. on BHK cells was determined. Subsequently, 50% inhibitory concentration (IC50% of the extract on replication of HSV-1 both in interacellular and exteracellular cases was assessed. Statistical Analysis: Statistic Probit model was used for statistical analysis. The dose-dependent effect of antiviral activity of the extracts was determined by linear regression. Results: Q. persica L. had no cytotoxic effect on this cell line. There was significant relationship between the concentration of the extract and cell death (P<0.01. IC50s of Q. persica L. on HSV-1, before and after attachment to BHK cells were 1.02 and 0.257 μg/mL, respectively. There was significant relationship between the concentration of this extract and inhibition of cytopathic effect (CPE (P<0.05. Antioxidant capacity of the extract was 67.5%. Conclusions: The hydroalchoholic extract of Q. persica L. is potentially an appropriate and promising anti herpetic herbal medicine.

Genetic and physiological characterization of two clusters of quantitative trait Loci associated with seed dormancy and plant height in rice.

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Ye, Heng; Beighley, Donn H; Feng, Jiuhuan; Gu, Xing-You

2013-02-01

Seed dormancy and plant height have been well-studied in plant genetics, but their relatedness and shared regulatory mechanisms in natural variants remain unclear. The introgression of chromosomal segments from weedy into cultivated rice (Oryza sativa) prompted the detection of two clusters (qSD1-2/qPH1 and qSD7-2/qPH7) of quantitative trait loci both associated with seed dormancy and plant height. Together, these two clusters accounted for >96% of the variances for plant height and ~71% of the variances for germination rate in an isogenic background across two environments. On the initial introgression segments, qSD1-2/qPH1 was dissected genetically from OsVp1 for vivipary and qSD7-2/qPH7 separated from Sdr4 for seed dormancy. The narrowed qSD1-2/qPH1 region encompasses the semidwarf1 (sd1) locus for gibberellin (GA) biosynthesis. The qSD1-2/qPH1 allele from the cultivar reduced germination and stem elongation and the mutant effects were recovered by exogenous GA, suggesting that sd1 is a candidate gene of the cluster. In contrast, the effect-reducing allele at qSD7-2/qPH7 was derived from the weedy line; this allele was GA-insensitive and blocked GA responses of qSD1-2/qPH1, including the transcription of a GA-inducible α-amylase gene in imbibed endosperm, suggesting that qSD7-2/qPH7 may work downstream from qSD1-2/qPH1 in GA signaling. Thus, this research established the seed dormancy-plant height association that is likely mediated by GA biosynthesis and signaling pathways in natural populations. The detected association contributed to weed mimicry for the plant stature in the agro-ecosystem dominated by semidwarf cultivars and revealed the potential benefit of semidwarf genes in resistance to preharvest sprouting.

Regulation of abscisic acid metabolism in relation to the dormancy and germination of cereal grains

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Justyna Fidler

2015-03-01

Full Text Available Seed dormancy is of particular importance in the cultivation of cereals, as it directly affects the quality of crop yield. If the dormancy period is too short, this may lead to pre-harvest sprouting, whereas a dormancy period that is too long may cause uneven germination; both of these scenarios are associated with economic losses. Most enzymes engaged in the metabolism of abscisic acid (ABA have been identified, and significant progress has been made in understanding the role of this phytohormone in the induction and maintenance of dormancy, mainly as a result of research conducted in Arabidopsis. Much less is known about the metabolism and function of ABA in cereal grains, especially in relation to dormancy and germination. This review focuses on the regulation of ABA metabolism in dormant and non-dormant cereal grains, in both the dry state and upon imbibition. Moreover, this review describes the influence of factors such as after-ripening, light, temperature, nitric oxide, and reactive oxygen species (ROS on the dormancy and germination of cereal grains. These factors, with the exception of ROS, appear to affect the level of dormancy and germination of grains through regulation of ABA metabolism.

Micropropagation of ornamental Prunus spp. and GF305 peach, a Prunus viral indicator.

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Kalinina, Anna; Brown, Daniel C W

2007-07-01

A micropropagation approach was developed for nine ornamental Prunus species, P. americana, P. cistena, P. glandulosa, P. serrulata 'Kwanzan', P. laurocerasus, P. sargentii, P. tomentosa, P. triloba, P. virginiana 'Schubert', commercially important in North America, and GF305 peach, commonly used for Prunus virus indexing. The micropropagation cycle based on proliferation of vegetative tissues includes establishment of tissue culture through introduction of shoot meristems in vitro, shoot proliferation, root induction and plant acclimatization steps and can be completed in 5 months. A meristem sterilization protocol minimized bacterial and fungal contamination. Multiple shoot formation in ornamental Prunus was obtained through the use of 1 mg l(-1) 6-benzyladenine. For GF305 peach, alteration in the sugar composition, fructose instead of sucrose, and addition of 1 mg l(-1 )ferulic acid had a significant impact on the shoot proliferation rate and maintenance of long-term in vitro culture. Rooting and plant acclimatization conditions were improved using a two-step protocol with a 4-day root induction in indole-3-butiric acid (IBA)-containing media with consequent 3-week root elongation in IBA-free media. One-month incubation of rooted shoots in a vermiculite-based medium resulted in additional shoot and root growth and provided better acclimatization and plant recovery. The micropropagation approach can be used for maintenance of the clonal properties for Prunus spp. as well as a protocol to support meristem therapy against viral infection.

A Case of Canine Borreliosis in Iran Caused by Borrelia persica

OpenAIRE

Shirani, Darush; Rakhshanpoor, Alaleh; Cutler, Sally J.; Ghazinezhad, Behnaz; Naddaf, Saied Reza

2016-01-01

Tick-borne relapsing fever is an endemic disease in Iran, with most cases attributed to infection by B. persica, which is transmitted by Ornithodoros tholozani soft ticks. Here, we report spirochetemia in blood of a puppy residing in Tehran, Iran. The causative species was identified by use of highly discriminative IGS sequencing; the 489 bp IGS sequence obtained in our study showed 99% identity (100% coverage) when compared with Borrelia persica sequences derived from clinical cases or from ...

Mutation of a nicotinic acetylcholine receptor β subunit is associated with resistance to neonicotinoid insecticides in the aphid Myzus persicae

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Field Linda M

2011-05-01

Full Text Available Abstract Background Myzus persicae is a globally important aphid pest with a history of developing resistance to insecticides. Unusually, neonicotinoids have remained highly effective as control agents despite nearly two decades of steadily increasing use. In this study, a clone of M. persicae collected from southern France was found, for the first time, to exhibit sufficiently strong resistance to result in loss of the field effectiveness of neonicotinoids. Results Bioassays, metabolism and gene expression studies implied the presence of two resistance mechanisms in the resistant clone, one based on enhanced detoxification by cytochrome P450 monooxygenases, and another unaffected by a synergist that inhibits detoxifying enzymes. Binding of radiolabeled imidacloprid (a neonicotinoid to whole body membrane preparations showed that the high affinity [3H]-imidacloprid binding site present in susceptible M. persicae is lost in the resistant clone and the remaining lower affinity site is altered compared to susceptible clones. This confers a significant overall reduction in binding affinity to the neonicotinoid target: the nicotinic acetylcholine receptor (nAChR. Comparison of the nucleotide sequence of six nAChR subunit (Mpα1-5 and Mpβ1 genes from resistant and susceptible aphid clones revealed a single point mutation in the loop D region of the nAChR β1 subunit of the resistant clone, causing an arginine to threonine substitution (R81T. Conclusion Previous studies have shown that the amino acid at this position within loop D is a key determinant of neonicotinoid binding to nAChRs and this amino acid change confers a vertebrate-like character to the insect nAChR receptor and results in reduced sensitivity to neonicotinoids. The discovery of the mutation at this position and its association with the reduced affinity of the nAChR for imidacloprid is the first example of field-evolved target-site resistance to neonicotinoid insecticides and also

Seed dormancy and germination - Emerging mechanisms and new hypotheses

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Hiroyuki eNonogaki

2014-05-01

Full Text Available Seed dormancy has played a significant role in adaptation and evolution of seed plants. While its biological significance is clear, molecular mechanisms underlying seed dormancy induction, maintenance and alleviation still remain elusive. Intensive efforts have been made to investigate gibberellin and abscisic acid metabolism in seeds, which greatly contributed to the current understanding of seed dormancy mechanisms. Other mechanisms, which might be independent of hormones, or specific to the seed dormancy pathway, are also emerging from genetic analysis of seed dormancy mutants. These studies suggest that chromatin remodeling through histone ubiquitination, methylation and acetylation, which could lead to transcription elongation or gene silencing, may play a significant role in seed dormancy regulation. Small interfering RNA and/or long non-coding RNA might be a trigger of epigenetic changes at the seed dormancy or germination loci, such as DELAY OF GERMINATION1. While new mechanisms are emerging from genetic studies of seed dormancy, novel hypotheses are also generated from seed germination study with high throughput gene expression analysis. Recent studies on tissue-specific gene expression in tomato and Arabidopsis seeds, which suggested possible mechanosensing in the regulatory mechanisms, advanced our understanding of embryo-endosperm interaction and have potential to re-draw the traditional hypotheses or integrate them into a comprehensive scheme. The progress in basic seed science will enable knowledge translation, another frontier of research to be expanded for food and fuel production.

Differences in the Detoxification Metabolism between Two clonal Lineages of the Aphid Myzus persicae (Sulzer (Hemiptera: Aphididae Reared on Tobacco (Nicotiana tabacum L. Diferencias en el Metabolismo de Detoxificación entre dos Linajes Clonales del Áfido Myzus persicae (Sulzer (Hemiptera: Aphididae creados sobre tabaco (Nicotiana tabacum L.

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Marco A Cabrera-Brandt

2010-12-01

Full Text Available Myzus persicae (Sulzer is a highly polyphagous aphid species, with a subspecies (M. persicae nicotianae well adapted to tobacco (Nicotiana tabacum L.. We evaluated the effect of this host plant on the aphid performance and detoxification enzymes, in order to test the participation of xenobiotic metabolism on the ability of this aphid to overcome the tobacco chemical defences. Two genotypes, one corresponding to the only M. persicae nicotianae genotype reported in Chile on tobacco, and one genotype belonging to M. persicae sensu stricto were reared on tobacco and pepper (Capsicum annuum L., respectively. M. persicae nicotianae showed a significantly higher intrinsic rate of increase (r m on pepper than on tobacco, and M. persicae s.s. performed similarly, but with no reproduction at all on tobacco. In order to evaluate the effect of tobacco on detoxification enzymes, esterases, glutathione S-transferases (GST and cytochrome P-450 monooxygenases (MO were determined in both selected aphid genotypes after 12, 24, 36, 48 and 72 h of rearing on tobacco and pepper. M. persicae nicotianae exhibited the higher total esterase activities when reared on tobacco than on pepper after 48 h of rearing, while the activities of GST and MO did not show any significant difference between host-plants and duration of treatment. For M. persicae s.s., no significant differences were observed among host-plants for the studied enzymes. These results suggest a participation of the esterases, on the ability of this M. persicae nicotianae to overcome the tobacco defences.Myzus persicae (Sulzer es un áfido polífago que incluye a Myzus persicae nicotianae, una subespecie altamente adaptada sobre tabaco (Nicotiana tabacum L.. Evaluamos el efecto del tabaco sobre el desempeño biológico y sobre determinadas enzimas de detoxificación en áfidos, para estudiar su participación en la capacidad de M. persicae nicotianae de superar las defensas químicas del tabaco. Dos

The Cloning and Functional Characterization of Peach CONSTANS and FLOWERING LOCUS T Homologous Genes PpCO and PpFT.

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Xiang Zhang

Full Text Available Flowering is an essential stage of plant growth and development. The successful transition to flowering not only ensures the completion of plant life cycles, it also serves as the basis for the production of economically important seeds and fruits. CONSTANS (CO and FLOWERING LOCUS T (FT are two genes playing critical roles in flowering time control in Arabidopsis. Through homology-based cloning and rapid-amplifications of cDNA ends (RACE, we obtained full-lengths cDNA sequences of Prunus persica CO (PpCO and Prunus persica FT (PpFT from peach (Prunus persica (L. Batsch and investigated their functions in flowering time regulation. PpCO and PpFT showed high homologies to Arabidopsis CO and FT at DNA, mRNA and protein levels. We showed that PpCO and PpFT were nucleus-localized and both showed transcriptional activation activities in yeast cells, consistent with their potential roles as transcription activators. Moreover, we established that the over-expression of PpCO could restore the late flowering phenotype of the Arabidopsis co-2 mutant, and the late flowering defect of the Arabidopsis ft-1 mutant can be rescued by the over-expression of PpFT, suggesting functional conservations of CO and FT genes in peach and Arabidopsis. Our results suggest that PpCO and PpFT are homologous genes of CO and FT in peach and they may function in regulating plant flowering time.

A molecular phylogeny of selected species of genus Prunus L ...

African Journals Online (AJOL)

(Syn. Prunus amygdalus) and Prunus cornuta (Wall. ex. Royle) Steudel. These are indigenous to Pakistan. In the ITS strict consensus results for example, the clade consisting of Laurocerasus, Padus and Cerasus subgenera are sister to the rest of the clades in the phylogenetic tree. Key words: Phylogeny, Prunus, Pakistan, ...

The effects of foliar fertilization with iron sulfate in chlorotic leaves are limited to the treated area. A study with peach trees (Prunus persica L. Batsch grown in the field and sugar beet (Beta vulgaris L. grown in hydroponics

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Hamdi eEl-Jendoubi

2014-01-01

Full Text Available Crop Fe deficiency is a worldwide problem. The aim of this study was to assess the effects of foliar Fe applications in two species grown in different environments: peach (Prunus persica L. Batsch trees grown in the field and sugar beet (Beta vulgaris L. cv. ‘Orbis’ grown in hydroponics. The distal half of Fe-deficient, chlorotic leaves was treated with Fe sulfate by dipping and using a brush in peach trees and sugar beet plants, respectively. The re-greening of the distal (Fe-treated and basal (untreated leaf areas was monitored, and the nutrient and photosynthetic pigment composition of the two areas were also determined. Leaves were also studied using chlorophyll fluorescence imaging, low temperature-scanning electron microscopy microanalysis, scanning transmission ion microscopy-particle induced X-ray emission and Perls Fe staining. The distal, Fe-treated leaf parts of both species showed a significant increase in Fe concentrations (across the whole leaf volume and marked re-greening, with significant increases in the concentrations of all photosynthetic pigments, as well as decreases in de-epoxidation of xanthophyll cycle carotenoids and increases in photochemical efficiency. In the basal, untreated leaf parts, Fe concentrations increased slightly, but little re-greening occurred. No changes in the concentrations of other nutrients were found. Foliar Fe fertilization was effective in re-greening treated leaf areas both in peach trees and sugar beet plants. Results indicate that the effects of foliar Fe-sulfate fertilization in Fe-deficient, chlorotic leaves were minor outside the leaf surface treated, indicating that Fe mobility within the leaf is a major constraint for full fertilizer effectiveness in crops where Fe-deficiency is established and leaf chlorosis occurs.

The effects of foliar fertilization with iron sulfate in chlorotic leaves are limited to the treated area. A study with peach trees (Prunus persica L. Batsch) grown in the field and sugar beet (Beta vulgaris L.) grown in hydroponics.

Science.gov (United States)

El-Jendoubi, Hamdi; Vázquez, Saúl; Calatayud, Angeles; Vavpetič, Primož; Vogel-Mikuš, Katarina; Pelicon, Primož; Abadía, Javier; Abadía, Anunciación; Morales, Fermín

2014-01-01

Crop Fe deficiency is a worldwide problem. The aim of this study was to assess the effects of foliar Fe applications in two species grown in different environments: peach (Prunus persica L. Batsch) trees grown in the field and sugar beet (Beta vulgaris L. cv. "Orbis") grown in hydroponics. The distal half of Fe-deficient, chlorotic leaves was treated with Fe sulfate by dipping and using a brush in peach trees and sugar beet plants, respectively. The re-greening of the distal (Fe-treated) and basal (untreated) leaf areas was monitored, and the nutrient and photosynthetic pigment composition of the two areas were also determined. Leaves were also studied using chlorophyll fluorescence imaging, low temperature-scanning electron microscopy microanalysis, scanning transmission ion microscopy-particle induced X-ray emission and Perls Fe staining. The distal, Fe-treated leaf parts of both species showed a significant increase in Fe concentrations (across the whole leaf volume) and marked re-greening, with significant increases in the concentrations of all photosynthetic pigments, as well as decreases in de-epoxidation of xanthophyll cycle carotenoids and increases in photochemical efficiency. In the basal, untreated leaf parts, Fe concentrations increased slightly, but little re-greening occurred. No changes in the concentrations of other nutrients were found. Foliar Fe fertilization was effective in re-greening treated leaf areas both in peach trees and sugar beet plants. Results indicate that the effects of foliar Fe-sulfate fertilization in Fe-deficient, chlorotic leaves were minor outside the leaf surface treated, indicating that Fe mobility within the leaf is a major constraint for full fertilizer effectiveness in crops where Fe-deficiency is established and leaf chlorosis occurs.

Relationship between weed dormancy and herbicide rotations: implications in resistance evolution.

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Darmency, Henri; Colbach, Nathalie; Le Corre, Valérie

2017-10-01

It is suggested that selection for late germinating seed cohorts is significantly associated with herbicide resistance in some cropping systems. In turn, it is conceivable that rotating herbicide modes of action selects for populations with mutations for increased secondary dormancy, thus partially overcoming the delaying effect of rotation on resistance evolution. Modified seed dormancy could affect management strategies - like herbicide rotation - that are used to prevent or control herbicide resistance. Here, we review the literature for data on seed dormancy and germination dynamics of herbicide-resistant versus susceptible plants. Few studies use plant material with similar genetic backgrounds, so there are few really comparative data. Increased dormancy and delayed germination may co-occur with resistance to ACCase inhibitors, but there is no clear-cut link with resistance to other herbicide classes. Population shifts are due in part to pleiotropic effects of the resistance genes, but interaction with the cropping system is also possible. We provide an example of a model simulation that accounts for genetic diversity in the dormancy trait, and subsequent consequences for various cropping systems. We strongly recommend adding more accurate and detailed mechanistic modelling to the current tools used today to predict the efficiency of prevention and management of herbicide resistance. These models should be validated through long-term experimental designs including mono-herbicide versus chemical rotation in the field. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

DOG1-imposed dormancy mediates germination responses to temperature cues

NARCIS (Netherlands)

Murphey, M.; Kovach, K.; Elnacash, T.; He, H.; Bentsink, L.; Donohue, K.

2015-01-01

Seed dormancy and environment-dependent germination requirements interact to determine the timing of germination in natural environments. This study tested the contribution of the dormancy gene Delay Of Germination 1 (DOG1) to primary and secondary dormancy induction in response to environmental

Regulation of seasonal patterns in seed dormancy

NARCIS (Netherlands)

Derkx, M.P.M.

1993-01-01

Buried seeds of many wild species pass annually through a pattern of induction and release of dormancy. These reversible changes in dormancy may be repeated for numbers of years when seeds are deprived from light and other germination-stimulating factors, and are a highly useful adaptation

Extensive transcriptome changes during natural onset and release of vegetative bud dormancy in Populus

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Glenn Thomas Howe

2015-12-01

Full Text Available To survive winter, many perennial plants become endodormant, a state of suspended growth maintained even in favorable growing environments. To understand vegetative bud endodormancy, we collected paradormant, endodormant, and ecodormant axillary buds from Populus trees growing under natural conditions. Of 44,441 Populus gene models analyzed using NimbleGen microarrays, we found that 1,362 (3.1% were differentially expressed among the three dormancy states, and another 429 (1.0% were differentially expressed during only one of the two dormancy transitions (false discovery rate p-value < 0.05. Of all differentially expressed genes, 69% were down-regulated from paradormancy to endodormancy, which was expected given the lower metabolic activity associated with endodormancy. Dormancy transitions were accompanied by changes in multiple genes associated with DNA methylation (via RNA-directed DNA methylation and histone modifications (via Polycomb Repressive Complex 2, confirming and extending knowledge of chromatin modification as major features of dormancy transitions. Among the chromatin-associated genes, we found two genes similar to SPT (SUPPRESSOR OF TY that were strongly up-regulated during endodormancy. Transcription factor genes and gene sets that were atypically up-regulated during endodormancy include a gene that seems to encode a trihelix transcription factor and genes associated with proteins involved in responses to ethylene, cold, and other abiotic stresses. These latter transcription factors include ETHYLENE INSENSITIVE 3 (EIN3, ETHYLENE-RESPONSIVE ELEMENT BINDING PROTEIN (EBP, ETHYLENE RESPONSE FACTOR (ERF, ZINC FINGER PROTEIN 10 (ZAT10, ZAT12, and WRKY DNA-binding domain proteins. Analyses of phytohormone-associated genes suggest important changes in responses to ethylene, auxin, and brassinosteroids occur during endodormancy. We found weaker evidence for changes in genes associated with salicylic acid and jasmonic acid, and little

Seed Anatomy and Water Uptake in Relation to Seed Dormancy in Opuntia tomentosa (Cactaceae, Opuntioideae)

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Orozco-Segovia, A.; Márquez-Guzmán, J.; Sánchez-Coronado, M. E.; Gamboa de Buen, A.; Baskin, J. M.; Baskin, C. C.

2007-01-01

Background and Aims There is considerable confusion in the literature concerning impermeability of seeds with ‘hard’ seed coats, because the ability to take up (imbibe) water has not been tested in most of them. Seeds of Opuntia tomentosa were reported recently to have a water-impermeable seed coat sensu lato (i.e. physical dormancy), in combination with physiological dormancy. However, physical dormancy is not known to occur in Cactaceae. Therefore, the aim of this study was to determine if seeds of O. tomentosa are water-permeable or water-impermeable, i.e. if they have physical dormancy. Methods The micromorphology of the seed coat and associated structures were characterized by SEM and light microscopy. Permeability of the seed-covering layers was assessed by an increase in mass of seeds on a wet substrate and by dye-tracking and uptake of tritiated water by intact versus scarified seeds. Key Results A germination valve and a water channel are formed in the hilum–micropyle region during dehydration and ageing in seeds of O. tomentosa. The funicular envelope undoubtedly plays a role in germination of Opuntia seeds via restriction of water uptake and mechanical resistance to expansion of the embryo. However, seeds do not exhibit any of three features characteristic of those with physical dormancy. Thus, they do not have a water-impermeable layer(s) of palisade cells (macrosclereids) or a water gap sensu stricto and they imbibe water without the seed coat being disrupted. Conclusions Although dormancy in seeds of this species can be broken by scarification, they have physiological dormancy only. Further, based on information in the literature, it is concluded that it is unlikely that any species of Opuntia has physical dormancy. This is the first integrative study of the anatomy, dynamics of water uptake and dormancy in seeds of Cactaceae subfamily Opuntioideae. PMID:17298989

A laboratory simulation of Arabidopsis seed dormancy cycling provides new insight into its regulation by clock genes and the dormancy-related genes DOG1, MFT, CIPK23 and PHYA.

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Footitt, Steven; Ölçer-Footitt, Hülya; Hambidge, Angela J; Finch-Savage, William E

2017-08-01

Environmental signals drive seed dormancy cycling in the soil to synchronize germination with the optimal time of year, a process essential for species' fitness and survival. Previous correlation of transcription profiles in exhumed seeds with annual environmental signals revealed the coordination of dormancy-regulating mechanisms with the soil environment. Here, we developed a rapid and robust laboratory dormancy cycling simulation. The utility of this simulation was tested in two ways: firstly, using mutants in known dormancy-related genes [DELAY OF GERMINATION 1 (DOG1), MOTHER OF FLOWERING TIME (MFT), CBL-INTERACTING PROTEIN KINASE 23 (CIPK23) and PHYTOCHROME A (PHYA)] and secondly, using further mutants, we test the hypothesis that components of the circadian clock are involved in coordination of the annual seed dormancy cycle. The rate of dormancy induction and relief differed in all lines tested. In the mutants, dog1-2 and mft2, dormancy induction was reduced but not absent. DOG1 is not absolutely required for dormancy. In cipk23 and phyA dormancy, induction was accelerated. Involvement of the clock in dormancy cycling was clear when mutants in the morning and evening loops of the clock were compared. Dormancy induction was faster when the morning loop was compromised and delayed when the evening loop was compromised. © 2017 The Authors Plant, Cell & Environment Published by John Wiley & Sons Ltd.

Proteome-Level Analysis of Metabolism- and Stress-Related Proteins during Seed Dormancy and Germination in Gnetum parvifolium.

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Chang, Ermei; Deng, Nan; Zhang, Jin; Liu, Jianfeng; Chen, Lanzhen; Zhao, Xiulian; Abbas, M; Jiang, Zeping; Shi, Shengqing

2018-03-21

Gnetum parvifolium is a rich source of materials for traditional medicines, food, and oil, but little is known about the mechanism underlying its seed dormancy and germination. In this study, we analyzed the proteome-level changes in its seeds during germination using isobaric tags for relative and absolute quantitation. In total, 1,040 differentially expressed proteins were identified, and cluster analysis revealed the distinct time points during which signal transduction and oxidation-reduction activity changed. Gene Ontology analysis showed that "carbohydrate metabolic process" and "response to oxidative stress" were the main enriched terms. Proteins associated with starch degradation and antioxidant enzymes were important for dormancy-release, while proteins associated with energy metabolism and protein synthesis were up-regulated during germination. Moreover, protein-interaction networks were mainly associated with heat-shock proteins. Furthermore, in accord with changes in the energy metabolism- and antioxidant-related proteins, indole-3-acetic acid, Peroxidase, and soluble sugar content increased, and the starch content decreased in almost all six stages of dormancy and germination analyzed (S1-S6). The activity of superoxide dismutase, abscisic acid, and malondialdehyde content increased in the dormancy stages (S1-S3) and then decreased in the germination stages (S4-S6). Our results provide new insights into G. parvifolium seed dormancy and germination at the proteome and physiological levels, with implications for improving seed propagation.

Cancer cells enter dormancy after cannibalizing mesenchymal stem/stromal cells (MSCs).

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Bartosh, Thomas J; Ullah, Mujib; Zeitouni, Suzanne; Beaver, Joshua; Prockop, Darwin J

2016-10-18

Patients with breast cancer often develop malignant regrowth of residual drug-resistant dormant tumor cells years after primary treatment, a process defined as cancer relapse. Deciphering the causal basis of tumor dormancy therefore has obvious therapeutic significance. Because cancer cell behavior is strongly influenced by stromal cells, particularly the mesenchymal stem/stromal cells (MSCs) that are actively recruited into tumor-associated stroma, we assessed the impact of MSCs on breast cancer cell (BCC) dormancy. Using 3D cocultures to mimic the cellular interactions of an emerging tumor niche, we observed that MSCs sequentially surrounded the BCCs, promoted formation of cancer spheroids, and then were internalized/degraded through a process resembling the well-documented yet ill-defined clinical phenomenon of cancer cell cannibalism. This suspected feeding behavior was less appreciable in the presence of a rho kinase inhibitor and in 2D monolayer cocultures. Notably, cannibalism of MSCs enhanced survival of BCCs deprived of nutrients but suppressed their tumorigenicity, together suggesting the cancer cells entered dormancy. Transcriptome profiles revealed that the resulting BCCs acquired a unique molecular signature enriched in prosurvival factors and tumor suppressors, as well as inflammatory mediators that demarcate the secretome of senescent cells, also referred to as the senescence-associated secretory phenotype. Overall, our results provide intriguing evidence that cancer cells under duress enter dormancy after cannibalizing MSCs. Importantly, our practical 3D coculture model could provide a valuable tool to understand the antitumor activity of MSCs and cell cannibalism further, and therefore open new therapeutic avenues for the prevention of cancer recurrence.

Concentration-mortality responses of Myzus persicae and natural enemies to selected insecticides.

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Bacci, Leandro; Rosado, Jander F; Picanço, Marcelo C; Pereira, Eliseu J G; Silva, Gerson A; Martins, Júlio C

2012-01-01

The toxicity of six insecticides was determined for the peach-potato aphid, Myzus persicae (Hemiptera: Aphididae), and some of its natural enemies - the predatory beetles Cycloneda sanguinea (Coccinellidae) and Acanthinus sp. (Anthicidae), and the wasp parasitoid Diaeretiella rapae (Aphidiidae). Natural enemies from these groups are important natural biological control agents in a number of agroecosystems, and insecticides potentially safe to these non-target organisms should be identified using standardized tests. Thus, concentration-mortality bioassays were carried out with both the aphid and its natural enemies to assess the toxicity and selectivity of acephate, deltamethrin, dimethoate, methamidophos, methyl parathion, and pirimicarb. The latter insecticide was highly selective to all natural enemies tested, and its LC(90) for M. persicae was 14-fold lower than the field rate recommended for control of the aphid in brassica crops. Methyl parathion also showed selectivity to C. sanguinea and Acanthinus sp., but not to D. rapae. Acephate was the least potent insecticide against M. persicae and was equally or more toxic to the natural enemies relative to the aphid. Pirimicarb and methyl parathion were efficient against M. persicae and selective in favor of two of the natural enemies tested. Acanthinus sp. and C. sanguinea were more tolerant to the insecticides than was the parasitoid D. rapae. This study shows that there are selective insecticides that may be compatible with conservation of natural enemies in brassica crops, which is important practical information to improve integrated pest management systems in these crops.

Prunus dulcis, Batch

African Journals Online (AJOL)

STORAGESEVER

2010-06-07

Jun 7, 2010 ... almond (Prunus dulcis, Batch) genotypes as revealed by PCR analysis. Yavar Sharafi1*, Jafar Hajilou1, Seyed AbolGhasem Mohammadi2, Mohammad Reza Dadpour1 and Sadollah Eskandari3. 1Department of Horticulture, Faculty of Agriculture, University of Tabriz, Tabriz, 5166614766, Iran.

Metagenomic analysis of buffalo rumen microbiome: Effect of roughage diet on Dormancy and Sporulation genes.

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Singh, K M; Reddy, B; Patel, A K; Panchasara, H; Parmar, N; Patel, A B; Shah, T M; Bhatt, V D; Joshi, C G

2014-12-01

Buffalo rumen microbiome experiences a variety of diet stress and represents reservoir of Dormancy and Sporulation genes. However, the information on genomic responses to such conditions is very limited. The Ion Torrent PGM next generation sequencing technology was used to characterize general microbial diversity and the repertoire of microbial genes present, including genes associated with Dormancy and Sporulation in Mehsani buffalo rumen metagenome. The research findings revealed the abundance of bacteria at the domain level and presence of Dormancy and Sporulation genes which were predominantly associated with the Clostridia and Bacilli taxa belonging to the phyla Firmicutes. Genes associated with Sporulation cluster and Sporulation orphans were increased from 50% to 100% roughage treatment, thereby promoting sporulation all along the treatments. The spore germination is observed to be the highest in the 75% roughage treatment both in the liquid and solid rumen fraction samples with respect to the decrease in the values of the genes associated with spore core dehydration, thereby facilitating spore core hydration which is necessary for spore germination.

[Effects of Beauveria bassiana on Myzus persicae and its two predaceous natural enemies].

Science.gov (United States)

Zhu, Hong; Luo, Xu-mei; Song, Jin-xin; Fan, Mei-zhen; Li, Zeng-zhi

2011-09-01

A Beauveria bassiana strain Bb21 was isolated from naturally infected green peach aphid Myzus persicae (Hemiptera: Aphididae). The effects of the strain on M. persicae and its two predaceous natural enemies Chrysoperla carnea (Neuroptera: Chrysopidae) and Harmonia axyridis (Coleoptera: Coccinellidae) were investigated under laboratory conditions. Bb21 had strong pathogenicity to M. persicae, with the LD50 of 97 conidia x mm(-2) (45-191, 95% confidence interval), but was less pathogenic to the second instar nymph of C. carnea, with the LD50 of 1089 conidia x mm(-2). The LD50 for C. carnea was 10.2 times higher than that for M. persicae. The pathogenicity of Bb21 to H. axyridis was very weak, with a low infection rate of 13% even at a high concentration 5 x 10(8) conidia x mL(-1). The Bb21 at low conidia concentration had less effect on the developmental period and fecundity of the two predaceous natural enemies. However, when applied at the high concentration 5 x 10(8) spores x mL(-1), Bb21 shortened the larval stage of H. axyridis averagely by 1.4 d and decreased the adult emergence rate and fecundity by 33% and 14%, respectively, and shortened the larval stage of C. carnea averagely by 0.7 d and decreased the adult emergence rate and fecundity by 24% and 11%, respectively. Since the LD50 for green peach aphid was much lower than that for the two predaceous natural enemies, and had very low effect on the adult emergence rate and fecundity of the two predators at the concentration recommended for field spray, Bb21 could be applied as a biocontrol agent of M. persicae in the integrated management of pernicious organisms.

Carbohydrate metabolism of vegetative and reproductive sinks in the late-maturing peach cultivar 'Encore'

Science.gov (United States)

Riccardo Lo Bianco; Mark Rieger; Shi-Jean S. Sung

1999-01-01

Activities of NAD+-dependent sorbitol dehydrogenase (SDH), sorbitol oxidase (SOX), sucrose synthase (SS), acid invertase (AI), and neutral invertase (NI) in ?Encore? peach (Prunus persica L.) fruits and developing shoot tips were assayed during the growing season to determine whether carbohydrate metabolizing enzymes could...

Differential dormancy of co-occurring copepods

Science.gov (United States)

Ohman, Mark D.; Drits, Aleksandr V.; Elizabeth Clarke, M.; Plourde, Stéphane

1998-08-01

Four species of planktonic calanoid copepods that co-occur in the California Current System ( Eucalanus californicus Johnson, Rhincalanus nasutus Giesbrecht, Calanus pacificus californicus Brodsky, and Metridia pacifica Brodsky) were investigated for evidence of seasonal dormancy in the San Diego Trough. Indices used to differentiate actively growing from dormant animals included developmental stage structure and vertical distribution; activity of aerobic metabolic enzymes (Citrate Synthase and the Electron Transfer System complex); investment in depot lipids (wax esters and triacylglycerols); in situ grazing activity from gut fluorescence; and egg production rates in simulated in situ conditions. None of the 4 species exhibited a canonical calanoid pattern of winter dormancy - i.e., synchronous developmental arrest as copepodid stage V, descent into deep waters, reduced metabolism, and lack of winter reproduction. Instead, Calanus pacificus californicus has a biphasic life history in this region, with an actively reproducing segment of the population in surface waters overlying a deep dormant segment in winter. Eucalanus californicus is dormant as both adult females and copepodid V's, although winter females respond relatively rapidly to elevated food and temperature conditions; they begin feeding and producing eggs within 2-3 days. Rhincalanus nasutus appears to enter dormancy as adult females, although the evidence is equivocal. Metridia pacifica shows no evidence of dormancy, with sustained active feeding, diel vertical migration behavior, and elevated activity of metabolic enzymes in December as well as in June. The four species also differ markedly in water content, classes of storage lipids, and specific activity of Citrate Synthase. These results suggest that copepod dormancy traits and structural composition reflect diverse adaptations to regional environmental conditions rather than a uniform, canonical series of traits that remain invariant among taxa

Recent advancements to study flowering time in almond and other Prunus species.

Science.gov (United States)

Sánchez-Pérez, Raquel; Del Cueto, Jorge; Dicenta, Federico; Martínez-Gómez, Pedro

2014-01-01

Flowering time is an important agronomic trait in almond since it is decisive to avoid the late frosts that affect production in early flowering cultivars. Evaluation of this complex trait is a long process because of the prolonged juvenile period of trees and the influence of environmental conditions affecting gene expression year by year. Consequently, flowering time has to be studied for several years to have statistical significant results. This trait is the result of the interaction between chilling and heat requirements. Flowering time is a polygenic trait with high heritability, although a major gene Late blooming (Lb) was described in "Tardy Nonpareil." Molecular studies at DNA level confirmed this polygenic nature identifying several genome regions (Quantitative Trait Loci, QTL) involved. Studies about regulation of gene expression are scarcer although several transcription factors have been described as responsible for flowering time. From the metabolomic point of view, the integrated analysis of the mechanisms of accumulation of cyanogenic glucosides and flowering regulation through transcription factors open new possibilities in the analysis of this complex trait in almond and in other Prunus species (apricot, cherry, peach, plum). New opportunities are arising from the integration of recent advancements including phenotypic, genetic, genomic, transcriptomic, and metabolomics studies from the beginning of dormancy until flowering.

Dispersal, dormancy and life-history tradeoffs at the individual, population and species levels in southern African Asteraceae.

Science.gov (United States)

de Waal, Caroli; Anderson, Bruce; Ellis, Allan G

2016-04-01

Dispersal and dormancy are important risk-reducing strategies in unpredictable environments. Negative covariation between these strategies is theoretically expected, but empirical evidence is limited and inconsistent. Moreover, covariation may be affected by other life-history traits and may vary across levels of biological organization. We assessed dispersal (vertical fall time of fruits, a proxy for wind dispersal ability) and dormancy (germination fractions measured during germination trials) in populations of 15 annual and 12 perennial wind-dispersed species in six Asteraceae genera from South Africa. Dormancy was higher in annuals than in perennials, whereas fall time was largely determined by evolutionary history. Controlling for phylogeny, dispersal and dormancy was negatively associated across species and life-history categories. Negative covariation between dispersal and dormancy was not evident at either the individual level (except for seed heteromorphic species) or the population level. Our study provides rare empirical support for the theoretical expectation of tradeoffs between dormancy and the alternative risk-reducing strategies, perenniality and dispersal, but refutes the expectation of increased dispersability in perennials. Although negative covariation between dispersal and dormancy at the species level appears not to be a simple consequence of upscaling individual-level mechanistic tradeoffs, our findings suggest that selection for one strategy may constrain evolution of the other. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

The evolution of insecticide resistance in the peach potato aphid, Myzus persicae.

Science.gov (United States)

Bass, Chris; Puinean, Alin M; Zimmer, Christoph T; Denholm, Ian; Field, Linda M; Foster, Stephen P; Gutbrod, Oliver; Nauen, Ralf; Slater, Russell; Williamson, Martin S

2014-08-01

The peach potato aphid, Myzus persicae is a globally distributed crop pest with a host range of over 400 species including many economically important crop plants. The intensive use of insecticides to control this species over many years has led to populations that are now resistant to several classes of insecticide. Work spanning over 40 years has shown that M. persicae has a remarkable ability to evolve mechanisms that avoid or overcome the toxic effect of insecticides with at least seven independent mechanisms of resistance described in this species to date. The array of novel resistance mechanisms, including several 'first examples', that have evolved in this species represents an important case study for the evolution of insecticide resistance and also rapid adaptive change in insects more generally. In this review we summarise the biochemical and molecular mechanisms underlying resistance in M. persicae and the insights study of this topic has provided on how resistance evolves, the selectivity of insecticides, and the link between resistance and host plant adaptation. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Gene expression profiles of Arabidopsis Cvi seeds during dormancy cycling indicate a common underlying dormancy control mechanism.

Science.gov (United States)

Cadman, Cassandra S C; Toorop, Peter E; Hilhorst, Henk W M; Finch-Savage, William E

2006-06-01

Physiologically dormant seeds, like those of Arabidopsis, will cycle through dormant states as seasons change until the environment is favourable for seedling establishment. This phenomenon is widespread in the plant kingdom, but has not been studied at the molecular level. Full-genome microarrays were used for a global transcript analysis of Arabidopsis thaliana (accession Cvi) seeds in a range of dormant and dry after-ripened states during cycling. Principal component analysis of the expression patterns observed showed that they differed in newly imbibed primary dormant seeds, as commonly used in experimental studies, compared with those in the maintained primary and secondary dormant states that exist during cycling. Dormant and after-ripened seeds appear to have equally active although distinct gene expression programmes, dormant seeds having greatly reduced gene expression associated with protein synthesis, potentially controlling the completion of germination. A core set of 442 genes were identified that had higher expression in all dormant states compared with after-ripened states. Abscisic acid (ABA) responsive elements were significantly over-represented in this set of genes the expression of which was enhanced when multiple copies of the elements were present. ABA regulation of dormancy was further supported by expression patterns of key genes in ABA synthesis/catabolism, and dormancy loss in the presence of fluridone. The data support an ABA-gibberelic acid hormone balance mechanism controlling cycling through dormant states that depends on synthetic and catabolic pathways of both hormones. Many of the most highly expressed genes in dormant states were stress-related even in the absence of abiotic stress, indicating that ABA, stress and dormancy responses overlap significantly at the transcriptome level.

Otostegia persica extraction on healing process of burn wounds

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Amin Ganjali

2013-06-01

Full Text Available PURPOSE: To investigate if the methanolic extract of the Otostegia persica can accelerating healing process of burn wound because of its anti-inflammatory and antioxidant effects. METHODS:Forty eight male Wistar rats were randomized into three study groups of 16 rats each. Burn wounds were created on dorsal part of shaved rats using a metal rod. In group I the burn wound was left without any treatment. Group was treated with topical silver sulfadiazine pomade. In group III, ointment containing the OP extract was administered. Skin biopsies were harvested from burn area on the 3rd, 5th, 14th and 21st days after burn and examined histologically. RESULTS: Re-epithelialization in the control group and in group II was lower than in group III. Re-epithelialization in groups II and III was significantly different from that in the control group. On the 5th day of the experiment, we assessed lower inflammation in the burn area compared to control group. This means that the inflammation was suppressed by methanolic extract of OP. From day 5 to 14; the fibroblast proliferation peaked and was associated with increased collagen accumulation. It was obvious that angiogenesis improved more in the groups II and III, which facilitated re-epithelialisation. CONCLUSION:Methanolic extract of Otostegia persica exhibited significant healing activity when topically applied on rats. OP is an effective treatment for saving the burn site.

Early growth performances of various seed sources of black (Prunus ...

African Journals Online (AJOL)

Early growth performances of various seed sources of black (Prunus serotina Erhr.) and wild cherry ( Prunus avium L.) seedlings on low and high elevation sites in the western Black Sea Region of Turkey.

Enraizamento in vitro de porta-enxertos de Prunus In vitro rooting of Prunus rootstocks

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Marcelo Rogalski

2003-08-01

Full Text Available Na micropropagação de Prunus sp., o enraizamento tem sido considerado uma fase crítica, pois determina a sobrevivência das plantas durante a aclimatização. Dentre os fatores importantes ao enraizamento in vitro, destacam-se o genótipo e as auxinas por serem determinantes na indução e na formação de raízes. O objetivo deste trabalho foi avaliar o efeito de diferentes concentrações de IBA no enraizamento in vitro dos porta-enxertos de espécies do gênero Prunus: cultivares Capdeboscq e GF677, e seleções VP411 e VP417. Para o enraizamento in vitro, brotos com 2-3cm de comprimento foram introduzidos em meio de Lepoivre suplementado com 0,1; 0,5; 1,0 e 2,0 mg.L-1 IBA. Observou-se que o porta-enxerto 'Capdeboscq' apresentou maior taxa de enraizamento e maior número de raízes in vitro, sendo superior aos demais genótipos quanto a estas características. O nível de 1,0 mg.L-1 de IBA esteve associado à maior taxa média de enraizamento (100%, 64% e 64,0%, respectivamente para os porta-enxertos 'Capdeboscq', 'GF677' e VP411. O nível de 2,0 mg.L-1 de IBA foi superior para a seleção VP417 com taxa de 64% de enraizamento. Para os porta-enxertos 'Capdeboscq' e 'GF677', o número máximo de raízes foi de 9,6 e 5,2 raízes por broto, respectivamente, em resposta ao nível de 2,0 mg.L-1 de IBA, enquanto as seleções VP411 e VP417 apresentaram o maior número de raízes (3,6 e 3,9, respectivamente em resposta ao nível de 1,0 mg.L-1 de IBA.In Prunus sp. micropropagation of rooting is considered a critical stage, since it determines the plant survival during the acclimatization. Among important factors associated with rooting, the genotype and the auxins are considered important in the induction and formation of roots. The objective of the present work was to evaluate the effect of different IBA on the in vitro rooting of Prunus rootstocks Capdeboscq and GF677, and the selections VP411 and VP417. For the in vitro rooting stage, shoots of

Redefining reproductive dormancy in Drosophila as a general stress response to cold temperatures.

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Lirakis, Manolis; Dolezal, Marlies; Schlötterer, Christian

2018-04-09

Organisms regularly encounter unfavorable conditions and the genetic adaptations facilitating survival have been of long-standing interest to evolutionary biologists. Winter is one particularly stressful condition for insects, during which they encounter low temperatures and scarcity of food. Despite dormancy being a well-studied adaptation to facilitate overwintering, there is still considerable controversy about the distribution of dormancy among natural populations and between species in Drosophila. The current definition of dormancy as developmental arrest of oogenesis at the previtellogenic stage (stage 7) distinguishes dormancy from general stress related block of oogenesis at early vitellogenic stages (stages 8 - 9). In an attempt to resolve this, we scrutinized reproductive dormancy in D. melanogaster and D. simulans. We show that dormancy shows the same hallmarks of arrest of oogenesis at stage 9, as described for other stressors and propose a new classification for dormancy. Applying this modified classification, we show that both species express dormancy in cosmopolitan and African populations, further supporting that dormancy uses an ancestral pathway induced by environmental stress. While we found significant differences between individuals and the two Drosophila species in their sensitivity to cold temperature stress, we also noted that extreme temperature stress (8 °C) resulted in very strong dormancy incidence, which strongly reduced the differences seen at less extreme temperatures. We conclude that dormancy in Drosophila should not be considered a special trait, but is better understood as a generic stress response occurring at low temperatures. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Reproductive dormancy in boll-weevil from populations of the midwest of Brazil.

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Paula, D P; Claudino, D; Timbó, R V; Miranda, J E; Bemquerer, M P; Ribeiro, A C J; Sujii, E R; Fontes, E M G; Pires, C S S

2013-02-01

The boll weevil (Anthonomus grandis Boheman) (Coleoptera: Curculionidae) is an introduced pest in Brazil, which in 30 yr has successfully expanded to various eco-regions and became the most important pest of cotton (Gossypium hirsutum, Malvaceae). Given the limited knowledge about the adaptive mechanisms that allowed successful establishment of the pest population in a tropical region, in this work we studied the potential of the Midwest population of boll weevils to enter a reproductive dormancy and identified the importance of the feeding source for induction of dormancy. We investigated morphological and physiological characters as indicators of the dormancy. We also investigated the occurrence of reproductive dormancy in boll weevils populations from cotton farms of the Midwestern region of Brazil during the cotton and noncotton seasons of 2009 and 2010. The studies revealed that boll weevils entered facultative reproductive dormancy; however, unlike what has been observed for boll weevils from temperate and subtropical regions, the hypertrophy of fat body and hexamerin levels did not straightly correlated to reproductive dormancy. The food source and field conditions during early adult development were decisive factor for the induction of reproductive dormancy. The incidence of reproductive dormancy increased progressively as the phenology of cotton plant advanced, reaching approximately 90% at the end of the crop season. During the noncotton season, the boll weevil was predominantly found in reproductive dormancy, especially females; however, there is evidence of use of multiple adaptive strategies to colonize the next harvest.

Maternal environment affects the genetic basis of seed dormancy in Arabidopsis thaliana.

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Postma, Froukje M; Ågren, Jon

2015-02-01

The genetic basis of seed dormancy, a key life history trait important for adaptive evolution in plant populations, has yet been studied only using seeds produced under controlled conditions in greenhouse environments. However, dormancy is strongly affected by maternal environmental conditions, and interactions between seed genotype and maternal environment have been reported. Consequently, the genetic basis of dormancy of seeds produced under natural field conditions remains unclear. We examined the effect of maternal environment on the genetic architecture of seed dormancy using a recombinant inbred line (RIL) population derived from a cross between two locally adapted populations of Arabidopsis thaliana from Italy and Sweden. We mapped quantitative trait loci (QTL) for dormancy of seeds produced in the greenhouse and at the native field sites of the parental genotypes. The Italian genotype produced seeds with stronger dormancy at fruit maturation than did the Swedish genotype in all three environments, and the maternal field environments induced higher dormancy levels compared to the greenhouse environment in both genotypes. Across the three maternal environments, a total of nine dormancy QTL were detected, three of which were only detected among seeds matured in the field, and six of which showed significant QTL × maternal environment interactions. One QTL had a large effect on dormancy across all three environments and colocalized with the candidate gene DOG1. Our results demonstrate the importance of studying the genetic basis of putatively adaptive traits under relevant conditions. © 2015 John Wiley & Sons Ltd.

On the role of abscisic acid in seed dormancy of red rice.

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Gianinetti, Alberto; Vernieri, Paolo

2007-01-01

Abscisic acid (ABA) is commonly assumed to be the primary effector of seed dormancy, but conclusive evidence for this role is lacking. This paper reports on the relationships occurring in red rice between ABA and seed dormancy. Content of free ABA in dry and imbibed caryopses, both dormant and after-ripened, the effects of inhibitors, and the ability of applied ABA to revert dormancy breakage were considered. The results indicate: (i) no direct correlation of ABA content with the dormancy status of the seed, either dry or imbibed; (ii) different sensitivity to ABA of non-dormant seed and seed that was forced to germinate by fluridone; and (iii) an inability of exogenous ABA to reinstate dormancy in fluridone-treated seed, even though applied at a pH which favoured high ABA accumulation. These considerations suggest that ABA is involved in regulating the first steps of germination, but unidentified developmental effectors that are specific to dormancy appear to stimulate ABA synthesis and to enforce the responsiveness to this phytohormone. These primary effectors appear physiologically to modulate dormancy and via ABA they effect the growth of the embryo. Therefore, it is suggested that ABA plays a key role in integrating the dormancy-specific developmental signals with the control of growth.

Dormancy contributes to the maintenance of microbial diversity.

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Jones, Stuart E; Lennon, Jay T

2010-03-30

Dormancy is a bet-hedging strategy used by a variety of organisms to overcome unfavorable environmental conditions. By entering a reversible state of low metabolic activity, dormant individuals become members of a seed bank, which can determine community dynamics in future generations. Although microbiologists have documented dormancy in both clinical and natural settings, the importance of seed banks for the diversity and functioning of microbial communities remains untested. Here, we develop a theoretical model demonstrating that microbial communities are structured by environmental cues that trigger dormancy. A molecular survey of lake ecosystems revealed that dormancy plays a more important role in shaping bacterial communities than eukaryotic microbial communities. The proportion of dormant bacteria was relatively low in productive ecosystems but accounted for up to 40% of taxon richness in nutrient-poor systems. Our simulations and empirical data suggest that regional environmental cues and dormancy synchronize the composition of active communities across the landscape while decoupling active microbes from the total community at local scales. Furthermore, we observed that rare bacterial taxa were disproportionately active relative to common bacterial taxa, suggesting that microbial rank-abundance curves are more dynamic than previously considered. We propose that repeated transitions to and from the seed bank may help maintain the high levels of microbial biodiversity that are observed in nearly all ecosystems.

Mapping X-Disease Phytoplasma Resistance in Prunus virginiana.

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Lenz, Ryan R; Dai, Wenhao

2017-01-01

Phytoplasmas such as " Candidatus Phytoplasma pruni," the causal agent of X-disease of stone fruits, lack detailed biological analysis. This has limited the understanding of plant resistance mechanisms. Chokecherry ( Prunus virginiana L.) is a promising model to be used for the plant-phytoplasma interaction due to its documented ability to resist X-disease infection. A consensus chokecherry genetic map "Cho" was developed with JoinMap 4.0 by joining two parental maps. The new map contains a complete set of 16 linkage groups, spanning a genetic distance of 2,172 cM with an average marker density of 3.97 cM. Three significant quantitative trait loci (QTL) associated with X-disease resistance were identified contributing to a total of 45.9% of the phenotypic variation. This updated genetic linkage map and the identified QTL will provide the framework needed to facilitate molecular genetics, genomics, breeding, and biotechnology research concerning X-disease in chokecherry and other Prunus species.

Mapping X-Disease Phytoplasma Resistance in Prunus virginiana

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Ryan R. Lenz

2017-11-01

Full Text Available Phytoplasmas such as “Candidatus Phytoplasma pruni,” the causal agent of X-disease of stone fruits, lack detailed biological analysis. This has limited the understanding of plant resistance mechanisms. Chokecherry (Prunus virginiana L. is a promising model to be used for the plant-phytoplasma interaction due to its documented ability to resist X-disease infection. A consensus chokecherry genetic map “Cho” was developed with JoinMap 4.0 by joining two parental maps. The new map contains a complete set of 16 linkage groups, spanning a genetic distance of 2,172 cM with an average marker density of 3.97 cM. Three significant quantitative trait loci (QTL associated with X-disease resistance were identified contributing to a total of 45.9% of the phenotypic variation. This updated genetic linkage map and the identified QTL will provide the framework needed to facilitate molecular genetics, genomics, breeding, and biotechnology research concerning X-disease in chokecherry and other Prunus species.

Mitogen-Activated Protein Kinase Kinase 3 Regulates Seed Dormancy in Barley.

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Nakamura, Shingo; Pourkheirandish, Mohammad; Morishige, Hiromi; Kubo, Yuta; Nakamura, Masako; Ichimura, Kazuya; Seo, Shigemi; Kanamori, Hiroyuki; Wu, Jianzhong; Ando, Tsuyu; Hensel, Goetz; Sameri, Mohammad; Stein, Nils; Sato, Kazuhiro; Matsumoto, Takashi; Yano, Masahiro; Komatsuda, Takao

2016-03-21

Seed dormancy has fundamental importance in plant survival and crop production; however, the mechanisms regulating dormancy remain unclear [1-3]. Seed dormancy levels generally decrease during domestication to ensure that crops successfully germinate in the field. However, reduction of seed dormancy can cause devastating losses in cereals like wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) due to pre-harvest sprouting, the germination of mature seed (grain) on the mother plant when rain occurs before harvest. Understanding the mechanisms of dormancy can facilitate breeding of crop varieties with the appropriate levels of seed dormancy [4-8]. Barley is a model crop [9, 10] and has two major seed dormancy quantitative trait loci (QTLs), SD1 and SD2, on chromosome 5H [11-19]. We detected a QTL designated Qsd2-AK at SD2 as the single major determinant explaining the difference in seed dormancy between the dormant cultivar "Azumamugi" (Az) and the non-dormant cultivar "Kanto Nakate Gold" (KNG). Using map-based cloning, we identified the causal gene for Qsd2-AK as Mitogen-activated Protein Kinase Kinase 3 (MKK3). The dormant Az allele of MKK3 is recessive; the N260T substitution in this allele decreases MKK3 kinase activity and appears to be causal for Qsd2-AK. The N260T substitution occurred in the immediate ancestor allele of the dormant allele, and the established dormant allele became prevalent in barley cultivars grown in East Asia, where the rainy season and harvest season often overlap. Our findings show fine-tuning of seed dormancy during domestication and provide key information for improving pre-harvest sprouting tolerance in barley and wheat. Copyright © 2016 Elsevier Ltd. All rights reserved.

Two Types of New Natural Materials for Fruit Vinegar in Prunus Plants

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Zhao Han

2017-01-01

Full Text Available To increase Prunus armeniaca × P. sibirica and P. domestica × P. armeniaca added value; three natural fruit vinegars were designed. The results showed the nutrition of Prunus domestica × P. armeniaca cultivar Fengweimeigui vinegar (T1 had high minerals and microelements, especially the Ca and Mg reached to the 150.00mg/L, 85.40 mg/L, respectively; the vinegar of Prunus armeniaca × P. sibirica cultivar Zhongren No.1 (T2 not only have rich Na (2800.00 mg/L, P (123.00 mg/L, but also have plentiful amino acid that content reached to 200.08 mg/L. However, the mixture vinegar (T3 with pulps from Prunus domestica × P. armeniaca and Prunus armeniaca × P. sibirica had the middle nutrient contents, but the property was balanced. We therefore conclude that solid fermentation is a suitable method to preserve nutrients and value-added for Prunus plants fruit, and three types vinegars are suitable for different age people, and the difference nutrient contents and typical characteristic indicate that three vinegars are competitive products in market.

Avaliação de inseticidas no controle de Myzus persicae (sulz. (homoptera: aphididae na cultura da alface Evaluation of insecticides to control Myzus persicae (Sulz (Homoptera: Aphididae on lettuce crop

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Jeferson Zagonel

2002-09-01

Full Text Available Foi avaliada a eficiência de inseticidas no controle de Myzus persicae (Sulz. na cultura da alface, cv. Verônica, em experimento conduzido na UEPG, em 1999. Usou-se delineamento experimental de blocos ao acaso com seis tratamentos e quatro repetições. Os tratamentos constaram de thiamethoxam nas doses de 50; 75 e 100 g i.a./ha; imidacloprid na dose de 140 g i.a./ha; pymetrozine na dose de 150 g i.a./ha e testemunha sem pulverização. Os tratamentos foram aplicados nas mudas em bandejas, um dia antes do transplantio. Avaliou-se a fitotoxicidade, o número de pulgões por planta, a porcentagem de plantas com pulgões e a eficiência dos inseticidas. O thiamethoxam nas doses de 50; 75 e 100 g i.a./ha foi eficiente no controle de M. persicae durante todo o ciclo, mostrando eficiência igual ou superior a 98,6%, similar ao imidacloprid. O pymetrozine apresentou eficiência no controle de M. persicae até 21 dias após o transplante das mudas. Os inseticidas não causaram efeitos fitotóxicos nas plantas de alface; além disso, houve produção de plantas com maior massa fresca em relação à testemunha.A field trial was carried out at Universidade Estadual de Ponta Grossa, State of Paraná, Brazil, in 1999, to evaluate the efficiency of insecticides in controlling Myzus persicae (Sulz on lettuce cv. Veronica. The experimental design was of completely randomized blocks with six treatments and four replications. The treatments consisted of thiamethoxam (50; 75 and 100 g i.a/ha imidacloprid (140 g i.a/ha; pymetrozine (150 g i.a/ha and control. The treatments were applied to seedlings grown in polyestyrene trays one day before the transplanting. The fitotoxicity, the number of aphids/plant, the percentage of plants with aphids and the efficiency of the insecticides were evaluated. Thiamethoxan at doses of 50; 75 and 100 g i.a/ha was efficient to control M. persicae from transplanting till 43 days after showing equal or higher efficiency than 98

Analysis of natural allelic variation at seed dormancy loci of Arabidopsis thaliana

NARCIS (Netherlands)

Alonso-Blanco, C.; Bentsink, L.; Hanhart, C.J.; Vries, de M.H.C.; Koornneef, M.

2003-01-01

Arabidopsis accessions differ largely in their seed dormancy behavior. To understand the genetic basis of this intraspecific variation we analyzed two accessions: the laboratory strain Landsberg erecta (Ler) with low dormancy and the strong-dormancy accession Cape Verde Islands (Cvi). We used a

Abscisic acid deficiency increases defence responses against Myzus persicae in Arabidopsis.

Science.gov (United States)

Hillwig, Melissa S; Chiozza, Mariana; Casteel, Clare L; Lau, Siau Ting; Hohenstein, Jessica; Hernández, Enrique; Jander, Georg; MacIntosh, Gustavo C

2016-02-01

Comparison of Arabidopsis thaliana (Arabidopsis) gene expression induced by Myzus persicae (green peach aphid) feeding, aphid saliva infiltration and abscisic acid (ABA) treatment showed a significant positive correlation. In particular, ABA-regulated genes are over-represented among genes that are induced by M. persicae saliva infiltration into Arabidopsis leaves. This suggests that the induction of ABA-related gene expression could be an important component of the Arabidopsis-aphid interaction. Consistent with this hypothesis, M. persicae populations induced ABA production in wild-type plants. Furthermore, aphid populations were smaller on Arabidopsis aba1-1 mutants, which cannot synthesize ABA, and showed a significant preference for wild-type plants compared with the mutant. Total free amino acids, which play an important role in aphid nutrition, were not altered in the aba1-1 mutant line, but the levels of isoleucine (Ile) and tryptophan (Trp) were differentially affected by aphids in wild-type and mutant plants. Recently, indole glucosinolates have been shown to promote aphid resistance in Arabidopsis. In this study, 4-methoxyindol-3-ylmethylglucosinolate was more abundant in the aba1-1 mutant than in wild-type Arabidopsis, suggesting that the induction of ABA signals that decrease the accumulation of defence compounds may be beneficial for aphids. © 2015 BSPP AND JOHN WILEY & SONS LTD.

HONSU, a protein phosphatase 2C, regulates seed dormancy by inhibiting ABA signaling in Arabidopsis.

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Kim, Woohyun; Lee, Yeon; Park, Jeongmoo; Lee, Nayoung; Choi, Giltsu

2013-04-01

Seed dormancy, a seed status that prohibits germination even in the presence of inductive germination signals, is a poorly understood process. To identify molecular components that regulate seed dormancy, we screened T-DNA insertion lines and identified a mutant designated honsu (hon). HON loss-of-function mutants display deep seed dormancy, whereas HON-overexpressing lines display shallow seed dormancy. HON encodes a seed-specific group A phosphatase 2C (PP2C) and is one of the major negative regulators of seed dormancy among group A PP2Cs. Like other PP2C family members, HON interacts with PYR1/RCAR11 in the presence of ABA. Our analysis indicates that HON inhibits ABA signaling and activates gibberellic acid signaling, and both of these conditions must be satisfied to promote the release of seed dormancy. However, HON mRNA levels are increased in mutants displaying deep seed dormancy or under conditions that deepen seed dormancy, and decreased in mutants displaying shallow seed dormancy or under conditions that promote the release of seed dormancy. Taken together, our results indicate that the expression of HON mRNA is homeostatically regulated by seed dormancy.

The Occurrence of the Cicada Cicadatra persica on Apple Trees, Malus domestica, in Erneh, Syria

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Dardar, Marah A.; Belal, Hamzeh M.R.; Basheer, Abedlnabi M.

2013-01-01

An infestation of Cicadatra persica KirKaldy (Hemiptera: Cicadidae) on apple trees, Malus domestica Borkhausen (Rosales: Rosaceae), was reported for the first time in the apple fruit orchards of Erneh, Syria. Nymphs, adults, exuvia, and exit holes in the soil were observed. The species was identified as C. persica based on morphological characters. Some biological observations and an acoustic analysis of the male's songs were also achieved. PMID:23909877

Proteomic analysis of embryogenesis and the acquisition of seed dormancy in Norway maple (Acer platanoides L.).

Science.gov (United States)

Staszak, Aleksandra Maria; Pawłowski, Tomasz Andrzej

2014-06-17

The proteome of zygotic embryos of Acer platanoides L. was analyzed via high-resolution 2D-SDS-PAGE and MS/MS in order to: (1) identify significant physiological processes associated with embryo development; and (2) identify changes in the proteome of the embryo associated with the acquisition of seed dormancy. Seventeen spots were identified as associated with morphogenesis at 10 to 13 weeks after flowering (WAF). Thirty-three spots were associated with maturation of the embryo at 14 to 22 WAF. The greatest changes in protein abundance occurred at 22 WAF, when seeds become fully mature. Overall, the stage of morphogenesis was characterized by changes in the abundance of proteins (tubulins and actin) associated with the growth and development of the embryo. Enzymes related to energy supply were especially elevated, most likely due to the energy demand associated with rapid growth and cell division. The stage of maturation is crucial to the establishment of seed dormancy and is associated with a higher abundance of proteins involved in genetic information processing, energy and carbon metabolism and cellular and antioxidant processes. Results indicated that a glycine-rich RNA-binding protein and proteasome proteins may be directly involved in dormancy acquisition control, and future studies are warranted to verify this association.

Haemangiosarcoma in a captive Asiatic lion ( Panthera leo persica ...

African Journals Online (AJOL)

A 2.7-year-old male captive Asiatic lion (Panthera leo persica) died unexpectedly without preceding symptoms. Gross necropsy revealed liver and lung tumours, which proved to be haemangiosarcomas by histopathology. Some of the liver tumours were ruptured, leading to massive intra-abdominal haemorrhage and death.

Host suitability analysis of the bark beetle Scolytus amygdali (Coleoptera: Curculionidae: Scolytinae).

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Zeiri, A; Ahmed, M Z; Braham, M; Qiu, B-L

2015-08-01

Scolytus amygdali is a polyphagous insect pest that feeds on fruit trees and forest trees. Our study assessed the host preference and reproductive potential of S. amygdali on four tree species: almond (Prunus dulcis), apricot (Prunus armeniaca), peach (Prunus persica), and plum (Prunus domestica). Females of S. amygdali produced maternal galleries that were longer on peach than the other three trees, and female fecundity was highest on peach. Females with longer maternal galleries produced more eggs, indicating a positive correlation between maternal gallery length and female fertility. The under-bark development time of S. amygdali is significantly shorter on plum (45 days) and almond (56 days) than on apricot (65 days) and peach (64 days). Despite this longer development time on peach, our results still suggest that, of the four types of tree tested, peach is the most preferred host for S. amygdali.

Effects of different methods of breaking dormancy and seed ...

African Journals Online (AJOL)

Seed dormancy in palms, date palm inclusive have continued to be challenging especially when cultivating through seeds. This study evaluated different methods of breaking dormancy and seed germination rate in P. dactylifera. Using Completely Randomize Design, two varieties of P. dactylifera were treated with three ...

Antidotal effects of varthemia persica DC extract in organophosphate poisoning or warfare agents by measuring whole blood acetylcholinesterase

International Nuclear Information System (INIS)

Kalantari, H.; Siahapoosh, A.; Farsani, K. M.

2009-01-01

The organophosphates (ORPs) or war fare agents toxicity results from inhibition of acetylcholinesterase (AchE). phosphylation of the active serin of AchE leads to accumulation of acetylcholine in synaptic clefts leading to generalized cholinergic over-stimulation. Standard treatment of ORP poisoning includes a muscarinic antagonist such as Atropine, and acetylcholinesterase reactivator (oxime). Presently, oximes like abidoxime and pralidoxime are approved as antidotes against ORP poisoning but are considered to be rather ineffective against certain ORP. Like Soman. In this study, the protective effect of Varthemia persica DC extract on acetylcholinesterase was examined in rats. Animals in weight range of 200-225 g were divided in 8 groups. The negative control group received only 0.4 ml normal saline, reference group, received ethylparaoxone in dose of 50 percent of LD50, positive control group, received ethylparaoxone (50% LD50) and one minute later 50 mol of pralidoxime. Test group 1: received ethylparaoxone and one minute later single dose of methanolic extract of Varthemia persica (250 mg/kg), Test Group 2: daily received methanolic extract of V.persica (250 mg/kg) in six days and one minute after last dose of extract, ethylparaoxone (50% LD50) were injected, Test Group 3: received ethylparaoxone (50% LD50) and then six doses of methanolic extract of V.persica (250 mg/kg) in six continuous days. Test Group 4: received ethylparaoxone and then single dose of dichloromethane extract of V.persica (250 mg/kg). Test Group 5: received ethylparaoxone and one minute later single high dose of methanolic extract of V.persica (1000 mg/kg). Then blood withdrawn and acetylcholinesterase activity was measured according to modified Ellman's method. Only in groups which received extract of V. persica before and after injection of ethylparaoxone, the mean of acetylcholinesterase activity was significantly different with reference group (p 0.05) but no significant difference with

Seed dormancy and germination vary within and among species of milkweeds

Science.gov (United States)

Kaye, Thomas N; Sandlin, Isaac J; Bahm, Matt A

2018-01-01

Abstract Pollinators in general and monarch butterflies in particular are in decline due to habitat loss. Efforts to restore habitats for insects that rely on specific plant groups as larvae or adults depend on the ability of practitioners to grow and produce these plants. Monarch larvae feed exclusively on milkweed species, primarily in the genus Asclepias, making propagation and restoration of these plants crucial for habitat restoration. Seed germination protocols for milkweeds are not well established, in part due to the large number of milkweed species and conflicting reports of seed dormancy in the genus. We tested for seed dormancy and the optimum period of cold stratification in 15 populations of A. speciosa and 1–2 populations of five additional species, including A. asperula, A. fascicularis, A. subulata, A. subverticillata and A. syriaca. We exposed seeds to cold (5 °C) moist conditions for 0, 2, 4, 6 and 8 weeks and then moved them to 15 °C/25 °C alternating temperatures. In A. speciosa, dormancy was detected in eight populations, and this dormancy was broken by 2–4 weeks of cold stratification. The remaining seven populations showed no dormancy. Seed dormancy was also detected in two populations of A. fascicularis (broken by 4–6 weeks of cold stratification) and a single population of A. syriaca (broken by 2 weeks of cold stratification). No dormancy was detected in A. asperula, A. subulata or A. subverticillata. Seed dormancy appears to be widespread in the genus (confirmed in 15 species) but can vary between populations even within the same species. Variation in seed dormancy and cold stratification requirements within and among Asclepias species suggests local adaptation and maternal environments may drive seedling ecology, and that growers should watch for low germination and use cold stratification as needed to maximize seed germination and retain genetic variability in restored populations. PMID:29593856

Spatial heterogeneity in post-dispersal predation on Prunus and Uvularia seeds.

Science.gov (United States)

Webb, Sara L; Willson, Mary F

1985-08-01

We investigated effects of seed density, distance from parent, and habitat (woods, open field) on post-dispersal predation risk (chiefly by rodents) for seeds of Prunus virginiana (Rosaceae). Additional study of the habitat effect (woods, open field, treefall gap) was made with seeds of Prunus avium (Rosaceae) and Uvularia grandiflora (Liliaceae). Density of Prunus seeds (range 2-40 seeds/group) did not affect predation risk for individual seeds. Distance from parent plants did influence predation risk, which was greatest directly beneath parents. This distance effect primarily comprised a sharp drop in risk within 2 m of parents, a distance too small to generate a "spacing rule" for conspecifics.We found that habitat strongly influenced predation intensity. Rates of removal of Prunus seeds were higher in woods than in open fields, except when overall predation intensity was very low and no pattern could be discerned. Prunus seed removal rates were higher in closed woods than in treefall gaps. Consequently, a Prunus seed will more likely escape predation if dispersed to an open site. In contrast, Uvularia seed removal rates were higher in open fields than in woods but did not differ between closed woods and tree-fall gaps.Predation intensity was spatially patchy between and within experimental arrays, but was consistent over time at some specific points in space, possibly reflecting home ranges of seed predators.

Seed storage-mediated dormancy alleviation in Fabaceae from campo rupestre

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Naïla Nativel

2015-09-01

Full Text Available ABSTRACTWe studied the effects of seed storage on germination and dormancy alleviation in three species of Fabaceae endemic to campo rupestrein southeastern Brazil. Fresh seeds of Collaea cipoensis, Mimosa maguirei and Mimosa foliolosawere set to germinate and germination of seeds after four, five and 13 years of storage was tested. Seed viability was maintained for all species after the full storage period. Seed storage significantly increased germination percentage and decreased germination time for C. cipoensisand M. foliolosa, suggesting the alleviation of physical dormancy with storage. However, we did not find evidence of dormancy alleviation in M. maguirei since stored seeds showed a decrease in germination in comparison to that of fresh seeds. Our data indicate species-specific storage-mediated dormancy alleviation, which will have important implications for restoration of campo rupestre.

Investigation on the pollen morphology of traditional cultivars of Prunus species in Sicily

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Anna Geraci

2012-08-01

Full Text Available In this study pollen grains of 13 cultivars and 3 rootstocks belonging to 5 species (P. armeniaca, P. domestica, P. dulcis, P. persica, P. avium of the genus Prunus collected from North-East Sicily were examined for the micromorphological characterization through the scanning electron microscopy (SEM. The length of polar axis (P and the equatorial diameter (E of grain, P/E ratio, the length of colpi (C, diameter of perforations (DP and the number of perforations in 25 μm2 (PN, the width of muri (WM, the distance between muri (DM and their number in 25 μm2 (MN, the width of grooves (WG were measured and their variation was compared among studied taxa. Moreover multivariate statistical analysis was carried out to distinguish morphometric information from measured parameters. All pollen grains are trizonocolpate, isopolar, medium-large sized and their shape varies from prolate to perprolate. Regarding outline pollen grains are subtriangular in polar view and elliptic in equatorial view. Exine sculpturing is striate with perforations on grain surface. The arrangement of ridges appears roughly parallel but too sloped (sometimes curved compared to polar axis, or branched and oriented in different directions, or perfectly parallel or more irregular with bifurcated ridges often sinuous. The analyses showed a great variability (particularly in P. domestica cultivars related in some cases to the diversity in the morphological features of the leaves and the fruits of the investigated entities.

Benzyl isothiocyanate, a major component from the roots of Salvadora persica is highly active against Gram-negative bacteria.

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Abier Sofrata

Full Text Available Plants produce a number of antimicrobial substances and the roots of the shrub Salvadora persica have been demonstrated to possess antimicrobial activity. Sticks from the roots of S. persica, Miswak sticks, have been used for centuries as a traditional method of cleaning teeth. Diverging reports on the chemical nature and antimicrobial repertoire of the chewing sticks from S. persica led us to explore its antibacterial properties against a panel of pathogenic or commensal bacteria and to identify the antibacterial component/s by methodical chemical characterization. S. persica root essential oil was prepared by steam distillation and solid-phase microextraction was used to sample volatiles released from fresh root. The active compound was identified by gas chromatography-mass spectrometry and antibacterial assays. The antibacterial compound was isolated using medium-pressure liquid chromatography. Transmission electron microscopy was used to visualize the effect on bacterial cells. The main antibacterial component of both S. persica root extracts and volatiles was benzyl isothiocyanate. Root extracts as well as commercial synthetic benzyl isothiocyanate exhibited rapid and strong bactericidal effect against oral pathogens involved in periodontal disease as well as against other Gram-negative bacteria, while Gram-positive bacteria mainly displayed growth inhibition or remained unaffected. The short exposure needed to obtain bactericidal effect implies that the chewing sticks and the essential oil may have a specific role in treatment of periodontal disease in reducing Gram-negative periodontal pathogens. Our results indicate the need for further investigation into the mechanism of the specific killing of Gram-negative bacteria by S. persica root stick extracts and its active component benzyl isothiocyanate.

Tanned or burned: the role of fire in shaping physical seed dormancy.

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Moreira, Bruno; Pausas, Juli G

2012-01-01

Plant species with physical seed dormancy are common in mediterranean fire-prone ecosystems. Because fire breaks seed dormancy and enhances the recruitment of many species, this trait might be considered adaptive in fire-prone environments. However, to what extent the temperature thresholds that break physical seed dormancy have been shaped by fire (i.e., for post-fire recruitment) or by summer temperatures in the bare soil (i.e., for recruitment in fire-independent gaps) remains unknown. Our hypothesis is that the temperature thresholds that break physical seed dormancy have been shaped by fire and thus we predict higher dormancy lost in response to fire than in response to summer temperatures. We tested this hypothesis in six woody species with physical seed dormancy occurring in fire-prone areas across the Mediterranean Basin. Seeds from different populations of each species were subject to heat treatments simulating fire (i.e., a single high temperature peak of 100 °C, 120 °C or 150 °C for 5 minutes) and heat treatments simulating summer (i.e., temperature fluctuations; 30 daily cycles of 3 hours at 31 °C, 4 hours at 43 °C, 3 hours at 33 °C and 14 hours at 18 °C). Fire treatments broke dormancy and stimulated germination in all populations of all species. In contrast, summer treatments had no effect over the seed dormancy for most species and only enhanced the germination in Ulex parviflorus, although less than the fire treatments. Our results suggest that in Mediterranean species with physical dormancy, the temperature thresholds necessary to trigger seed germination are better explained as a response to fire than as a response to summer temperatures. The high level of dormancy release by the heat produced by fire might enforce most recruitment to be capitalized into a single post-fire pulse when the most favorable conditions occur. This supports the important role of fire in shaping seed traits.

Tanned or burned: the role of fire in shaping physical seed dormancy.

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Bruno Moreira

Full Text Available Plant species with physical seed dormancy are common in mediterranean fire-prone ecosystems. Because fire breaks seed dormancy and enhances the recruitment of many species, this trait might be considered adaptive in fire-prone environments. However, to what extent the temperature thresholds that break physical seed dormancy have been shaped by fire (i.e., for post-fire recruitment or by summer temperatures in the bare soil (i.e., for recruitment in fire-independent gaps remains unknown. Our hypothesis is that the temperature thresholds that break physical seed dormancy have been shaped by fire and thus we predict higher dormancy lost in response to fire than in response to summer temperatures. We tested this hypothesis in six woody species with physical seed dormancy occurring in fire-prone areas across the Mediterranean Basin. Seeds from different populations of each species were subject to heat treatments simulating fire (i.e., a single high temperature peak of 100 °C, 120 °C or 150 °C for 5 minutes and heat treatments simulating summer (i.e., temperature fluctuations; 30 daily cycles of 3 hours at 31 °C, 4 hours at 43 °C, 3 hours at 33 °C and 14 hours at 18 °C. Fire treatments broke dormancy and stimulated germination in all populations of all species. In contrast, summer treatments had no effect over the seed dormancy for most species and only enhanced the germination in Ulex parviflorus, although less than the fire treatments. Our results suggest that in Mediterranean species with physical dormancy, the temperature thresholds necessary to trigger seed germination are better explained as a response to fire than as a response to summer temperatures. The high level of dormancy release by the heat produced by fire might enforce most recruitment to be capitalized into a single post-fire pulse when the most favorable conditions occur. This supports the important role of fire in shaping seed traits.

Diversity of Xylella fastidiosa host suitability among siblings from a non-traditional almond X peach cross

Science.gov (United States)

Ten F2 clones from an initial hybridization of Prunus webbii X P. persica cv Harrow Blood were evaluated under greenhouse conditions for their reaction to Xylella fastidiosa subsp. fastidiosa strain M23 during two growing seasons. Clonal accessions used for the study were selected on the basis of ho...

Cancer dormancy and criticality from a game theory perspective.

Science.gov (United States)

Wu, Amy; Liao, David; Kirilin, Vlamimir; Lin, Ke-Chih; Torga, Gonzalo; Qu, Junle; Liu, Liyu; Sturm, James C; Pienta, Kenneth; Austin, Robert

2018-01-01

The physics of cancer dormancy, the time between initial cancer treatment and re-emergence after a protracted period, is a puzzle. Cancer cells interact with host cells via complex, non-linear population dynamics, which can lead to very non-intuitive but perhaps deterministic and understandable progression dynamics of cancer and dormancy. We explore here the dynamics of host-cancer cell populations in the presence of (1) payoffs gradients and (2) perturbations due to cell migration. We determine to what extent the time-dependence of the populations can be quantitively understood in spite of the underlying complexity of the individual agents and model the phenomena of dormancy.

Uso de cuatro extractos organicos para el control del pulgon verde (Myzus persicae Sulz) (ING)

OpenAIRE

Rodríguez Navas, Hernán; Blanco, Fabio A.

2016-01-01

Extracts of leaves and stems of Neurolaena lobata; leaves, stems and fruits of Momordica charantia, wood of Quassia amara and seeds of Annona muricata, were tested regarding their effectiveness for control of green peach aphid (Myzus persicae). In a first stage, groups of 10 individuals of M. persicae were placed inside petri dishes together with a small and slight piece of synthetic cloth soaked with either substance extracted. Several concentrations were used. After two hours; more than 50%...

Caracterización con RAMs de la colección de durazno (Prunus persica L. Batsch existente en la Universidad Pedagógica y Tecnológica de Colombia

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Ana Cruz Morillo Coronado

2014-12-01

Full Text Available Utilizando ocho cebadores Microsatélites Amplificados al Azar (RAMs fue evaluada la diversidad genética de 31 materiales de Prunus de la colección de caducifolios existente en la Universidad Pedagógica y Tecnológica de Colombia. Se generaron un total de 121 amplicones con pesos moleculares entre 260 y 1000 Kb. Con un coeficiente de similitud de 0.75, se formaron tres grupos, de acuerdo principalmente con las características del fruto, encontrando en el grupo 2 las variedades de importancia económica. El número de loci polimórficos varió entre 5 y 16 para los cebadores GT y CCA, respectivamente. El valor promedio de heterocigosidad fue de 0.22, más bajo que los encontrados en otros estudios de diversidad genética en el género Prunus; por tanto, se deben buscar estrategias para incrementar la variabilidad genética de la colección como la introducción de nuevos materiales o híbridos interespecíficos. La técnica RAMs es útil para evaluar la diversidad genética en especies caducifolias.

A Proteomic Signature of Dormancy in the Actinobacterium Micrococcus luteus.

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Mali, Sujina; Mitchell, Morgan; Havis, Spencer; Bodunrin, Abiodun; Rangel, Jonathan; Olson, Gabriella; Widger, William R; Bark, Steven J

2017-07-15

Dormancy is a protective state in which diverse bacteria, including Mycobacterium tuberculosis , Staphylococcus aureus , Treponema pallidum (syphilis), and Borrelia burgdorferi (Lyme disease), curtail metabolic activity to survive external stresses, including antibiotics. Evidence suggests dormancy consists of a continuum of interrelated states, including viable but nonculturable (VBNC) and persistence states. VBNC and persistence contribute to antibiotic tolerance, reemergence from latent infections, and even quorum sensing and biofilm formation. Previous studies indicate that the protein mechanisms regulating persistence and VBNC states are not well understood. We have queried the VBNC state of Micrococcus luteus NCTC 2665 (MI-2665) by quantitative proteomics combining gel electrophoresis, high-performance liquid chromatography, and tandem mass spectrometry to elucidate some of these mechanisms. MI-2665 is a nonpathogenic actinobacterium containing a small (2.5-Mb), high-GC-content genome which exhibits a well-defined VBNC state induced by nutrient deprivation. The MI-2665 VBNC state demonstrated a loss of protein diversity accompanied by increased levels of 18 proteins that are conserved across actinobacteria, 14 of which have not been previously identified in VNBC. These proteins implicate an anaplerotic strategy in the transition to VBNC, including changes in the glyoxylate shunt, redox and amino acid metabolism, and ribosomal regulatory processes. Our data suggest that MI-2665 is a viable model for dissecting the protein mechanisms underlying the VBNC stress response and provide the first protein-level signature of this state. We expect that this protein signature will enable future studies deciphering the protein mechanisms of dormancy and identify novel therapeutic strategies effective against antibiotic-tolerant bacterial infections. IMPORTANCE Dormancy is a protective state enabling bacteria to survive antibiotics, starvation, and the immune system

Coniochaeta (Lecythophora), Collophora gen. nov. And Phaeomoniella species associated with wood necroses of Prunus trees

NARCIS (Netherlands)

Damm, U.; Fourie, P.H.; Crous, P.W.

2010-01-01

Species of the genus Coniochaeta (anamorph: Lecythophora) are known as pathogens of woody hosts, but can also cause opportunistic human infections. Several fungi with conidial stages resembling Lecythophora were isolated from necrotic wood samples of Prunus trees in South Africa. In order to reveal

Mechanisms of Cancer Cell Dormancy – Another Hallmark of Cancer?

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Yeh, Albert C.; Ramaswamy, Sridhar

2015-01-01

Disease relapse in cancer patients many years after clinical remission, often referred to as cancer dormancy, is well documented but remains an incompletely understood phenomenon on the biological level. Recent reviews have summarized potential models that can explain this phenomenon, including angiogenic, immunologic, and cellular dormancy. We focus on mechanisms of cellular dormancy as newer biological insights have enabled better understanding of this process. We provide a historical context, synthesize current advances in the field, and propose a mechanistic framework that treats cancer cell dormancy as a dynamic cell state conferring a fitness advantage to an evolving malignancy under stress. Cellular dormancy appears to be an active process that can be toggled through a variety of signaling mechanisms that ultimately down-regulate the Ras/MAPK and PI(3)K/AKT pathways, an ability that is preserved even in cancers that constitutively depend on these pathways for their growth and survival. Just as unbridled proliferation is a key hallmark of cancer, the ability of cancer cells to become quiescent may be critical to evolving malignancies, with implications for understanding cancer initiation, progression, and treatment resistance. PMID:26354021

Water Recovery System Architecture and Operational Concepts to Accommodate Dormancy

Science.gov (United States)

Carter, Layne; Tabb, David; Anderson, Molly

2017-01-01

Future manned missions beyond low Earth orbit will include intermittent periods of extended dormancy. The mission requirement includes the capability for life support systems to support crew activity, followed by a dormant period of up to one year, and subsequently for the life support systems to come back online for additional crewed missions. NASA personnel are evaluating the architecture and operational concepts that will allow the Water Recovery System (WRS) to support such a mission. Dormancy could be a critical issue due to concerns with microbial growth or chemical degradation that might prevent water systems from operating properly when the crewed mission began. As such, it is critical that the water systems be designed to accommodate this dormant period. This paper identifies dormancy issues, concepts for updating the WRS architecture and operational concepts that will enable the WRS to support the dormancy requirement.

Effect of pre-germination treatments on the dormancy breaking and ...

African Journals Online (AJOL)

The demand for bitter kola (Garcinia kola) is high in Nigeria market but the population of the species is low both in the wild and home gardens. Rapid deforestation, heavy exploitation in the natural forest and difficulties associated with its germination occasioned by seed dormancy have been blamed. The study on ...

A molecular phylogeny of selected species of Genus Prunus L ...

African Journals Online (AJOL)

Administrator

2011-05-30

May 30, 2011 ... The genus Prunus L. is an important plant for fruit production and it includes plums, apricots, cherries, almonds ... classification and placement of different genera under different sub-families. ... cultivated primarily or their beautiful flowers, such as ..... described the character evolution in the 37 Prunus and 8.

Microsatellite marker analysis of peach-potato aphids (Myzus persicae, Homoptera: Aphididae) from Scottish suction traps.

Science.gov (United States)

Malloch, G; Highet, F; Kasprowicz, L; Pickup, J; Neilson, R; Fenton, B

2006-12-01

The peach-potato aphid Myzus persicae (Sulzer) is an important vector of plant viruses. A network of suction traps collects aerial samples of this aphid in order to monitor and help predict its spatial distribution and likely impact on virus transmission in crops. A suction trap catch is thought to be a good representation of the total aphid pool. Sensitive molecular markers have been developed that determine the genetic composition of the M. persicae population. In Scotland, UK, these were applied to field collections revealing a limited number of clones. Molecular markers are less successful when applied to specimens that have been preserved in an ethanol-based trap fluid designed to preserve morphology. An assessment of different DNA extraction and PCR techniques is presented and the most efficient are used to analyse M. persicae specimens caught in the Dundee suction trap in 2001, a year when exceptionally high numbers were caught. The results reveal that the majority of the M. persicae caught belonged to two highly insecticide resistant clones. In addition, it was possible to compare the relative frequencies of genotypes caught in the trap with those collected at insecticide treated and untreated field sites in the vicinity. These results indicate that, in addition to suction trap data, the ability to sample field sites provides valuable early warning data which have implications for pest control and virus management strategies.

Antimicrobial Efficacy of Salvadora persica Extracts on a Monospecies Biofilm on Orthodontic Brackets In Vitro.

Science.gov (United States)

Halawany, Hassan S; Abraham, Nimmi B; Siddiqui, Yunus M; Balto, Hanan A; Jacob, Vimal

2016-01-01

The oral cavity is a rich ecosystem with a plethora of microorganisms, and different components of fixed orthodontic appliances may contribute to a shift in the balance of oral ecology. The purpose of this study was to investigate the antimicrobial potential of hexane and ethanol extracts of Salvadora persica on a monospecies biofilm model established on orthodontic brackets in vitro. Streptococcus mutans biofilm was formed on mini diamond orthodontic brackets following three days of anaerobic incubation at 37˚C. The bacterial cell viability of this biofilm was measured after their exposure to saline, hexane extract of S. persica, ethanol extract of S. persica and 0.2% chlorhexidine using 3-(4, 5-dimethylthiazol- 2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) assay. On half of the brackets, the colony forming units (CFU) were counted. Both experiments were performed in triplicate. The absorbance values obtained from the MTS reduction assay after exposure to the different test agents showed a decline in the bacterial cell viability of the S. mutans biofilm as follows: chlorhexidine (+)0.05). The CFU counts of S. mutans obtained from chlorhexidine exposure were lower than from hexane and ethanol extracts. S. persica extracts were found to have antimicrobial effects on S. mutans biofilm established in vitro on orthodontic brackets suggestive of its potential use as an oral antimicrobial agent for orthodontic patients.

Maturation, temperature and breaking dormancy of Comanthera seeds

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Andréa Santos Oliveira

2016-09-01

Full Text Available Given the importance of “everlasting” plants for their ornamental value and vulnerability to extractive practices, studies to ensure the propagation of the species are indispensable. The aim of this study was to assess whether there is an association between seed coat color and the quality of everlasting seeds, in the presence or absence of dormancy. Four species (Comanthera elegans, C. nitida, C. bisculata, and Comanthera sp. were separated with respect to seed coat color and underwent germination first count, germination, and germination speed index testing in a substrate moistened with water or 0.1% fluridone solution, in alternating temperatures of 10/25°C and 15/25°C. A completely randomized experimental design was used in a 4 x 2 x 2 factorial arrangement [seed coat color (green, beige, red, brown × temperature (10/25°C and 15/25°C × dormancy breaking (with or without]. In general, the alternating 15/25°C temperature is favorable for germination of everlasting plants. The use of fluridone is favorable to germination and seed vigor, especially when using the alternating temperature of 10/25°C. The effect of seed coat color varies among species; higher germination and vigor values are seen in green seeds for Comanthera sp. and lower values in C. bisculata. For C. nitida and C. elegans, seed coat color does not influence seed quality. Direct relationships between fluoridone efficiency in breaking dormancy of seeds of different species of everlasting plants and classification in different colors are not observed.

Susceptibility of Australian Myzus persicae (Hemiptera: Aphididae) to Three Recently Registered Insecticides: Spirotetramat, Cyantraniliprole, and Sulfoxaflor.

Science.gov (United States)

de Little, Siobhan C; Umina, Paul A

2017-08-01

The green peach aphid, Myzus persicae (Sulzer), is a significant agricultural pest that has developed resistance to a large number of insecticides globally. Within Australia, resistance has previously been confirmed for multiple chemical groups, including pyrethroids, carbamates, organophosphates, and neonicotinoids. In this study, we use leaf-dip and topical bioassays to investigate susceptibility and potential cross-resistance of 12 field-collected populations of Australian M. persicae to three recently registered insecticides: sulfoxaflor, spirotetramat, and cyantraniliprole. Despite all 12 populations carrying known resistance mechanisms to carbamates, organophosphates, and pyrethroids, and two populations also exhibiting low-level metabolic resistance to neonicotinoids, we found little evidence of variation in susceptibility to sulfoxafor, spirotetramat, or cyantraniliprole. This provides further evidence that cross-resistance to spirotetramat, cyantraniliprole, and sulfoxaflor in M. persicae is not conferred by the commonly occurring resistance mechanisms MACE, super-kdr, amplification of the E4 esterase gene, or enhanced expression and copy number of the P450 gene, CYP6CY3. Importantly, this study also established toxicity baseline data that will be important for future monitoring of insecticide responses of M. persicae from both broadacre and horticultural crops. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Evaluation of some indices selection traits of the “HS314” genotype ...

African Journals Online (AJOL)

Interspecific hybrids, especially in prunus genus, are used as rootstocks for stone fruit trees in the world, in recent decades. In this research, 106 interspesific hybrids including: almond × peach (P. amygdalus ×P. persica ) , almond × prune (P. amygdalus × P. cerasifera ), apricot × prune (P. armeniaca × P. cerasifera ) and ...

Crystal Macropattern Development in Prunus serotina (Rosaceae, Prunoideae) Leaves

OpenAIRE

LERSTEN, NELS R.; HORNER, HARRY T.

2006-01-01

• Background and Aims Prunus, subgenus Padus, exhibits two completely different calcium oxalate crystal macropatterns in mature leaves. Foliar macropattern development has been described previously in P. virginiana, representing one version. Prunus serotina, in the group exhibiting the second macropattern, is described here. The goal was to describe developmental details for comparison with P. virginiana, and to extend the sparse current knowledge of crystal macropatterns.

An in vivo evaluation of antimicrobial effects of Persica herbal mouthwash on Candida albicans and Enterococcus faecalis

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Leila Shafiei Bafti

2013-11-01

Full Text Available BACKGROUND AND AIM: Due to their antimicrobial and dental plaque control activity, mouthwashes lead to an improvement in oral health. Although chemical mouthwashes have demonstrated the greatest antimicrobial and anti-inflammatory effects, their usage has been limited because of their numerous side effects. This study was conducted in vivo to determine the antibacterial and antifungal effects of Persica herbal mouthwash containing Salvadore persica, mint, and yarrow in comparison with a placebo. METHODS: In this experimental, single-blind study, 80 dentistry students, who were eager to participate in the study, were randomly allocated into two groups of forty. One group was given Persica while the other group received a placebo. They were asked to apply the mouthwash twice a day for four weeks. The participants were unaware of the mouthwash type. Saliva sampling was conducted in all cases before and after mouthwash application and the samples were dispatched to a laboratory for microbial culture (Sabouraud and Clark-Kenner media culture. After two weeks, the washout times in groups were swapped with each other and the sampling was conducted just like before. Finally, the data were analyzed using independent and paired t-test. P values of less than 0.05 were considered significant. RESULTS: The mean age of participants was 23.20 ± 4.14. Persica mouthwash significantly decreased the count of Candida albicans (1.43 ± 0.15 to 0.8 ± 0.35 (P < 0.001 and Enterococcus faecalis (0.93 ± 1.76 to 0.71 ± 2.10 (P = 0.008. CONCLUSION: The statistical tests revealed that applying Persica mouthwash would result in a significant decrease in the Candida albicans and Enterococcus faecalis count. Regarding the significant and desirable effect of Persica on Candida albicans and Enterococcus faecalis, and its herbal origin, its application could be suggested to reduce oral microbes and infections from fungi and enterococci.

Characterization of sour (Prunus cerasus L. and sweet cherry (Prunus avium L. varieties with five isozyme systems Caracterização de variedades de ginjeira (Prunus cerasus L. e cerejeira (Prunus avium L. em cinco sistemas isoenzimáticos

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Remedios Morales Corts

2008-03-01

Full Text Available Extracts from young leaves of nine sweet cherry (Prunus avium L. and eight sour cherry (Prunus cerasus L. varieties, located in the germplasm collection of the 'Direção Regional de Agricultura da Beira Interior' (Fundão, Portugal, were analysed for five isozyme systems in order to characterise these varieties and detect problems of synonymies and homonymies that frequently present. The sweet and sour cherry varieties analyzed showed low isoenzymatic polymorphism, being PGM and PGI the systems with the highest discrimination power. These systems presented seven and five different zymogrames, respectively. IDH showed four patterns. SKDH and 6-PGD grouped the varieties only into two patterns. The evident and discriminant restrictions of this type of analysis had got results that have only been a complement for agronomical and morphological characterization.Nove extratos de folhas com desenvolvimento encompleto foram obtidos de 9 variedades de cerejeira (Prunus avium L. e 8 de ginjeira (Prunus cerasus L., localizados no campo de germoplasma da "Direcção Regional de Agricultura da Beira Interior" (Fundão, Portugal. Esses extratos foram analisados para 5 sistemas isoenzimáticos a fim de caracterizar essas variedades e simultaneamente detectar sinonímias e homonímias, freqüentes neste tipo de estudos. As variedades de cerejeira e ginjeira analisadas mostraram baixo polimorfismo isoenzimático, sendo que os sistemas PGM e PGI mostraram maior poder de discriminação. Estes sistemas apresentaram 7 e 5 zimogramas diferentes, respectivamente. IDH mostrou 4 padrões. SKDH e 6-PGD agruparam as variedades em 2 padrões. Os evidentes limites discriminatórios desse tipo de análise serviram somente de complemento para a caracterização agronômica e morfológica.

Antibacterial efficacy of Salvadora persica as a cleansing teeth towards Streptococcus mutans and Lactobacilli colonies

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Erlina Sih Mahanani

2012-12-01

Full Text Available Background: Salvadora persica is a traditional chewing stick for cleaning teeth that it is known Siwak. Several studies have demonstrated the antimicrobial effects of Salvadora persica. Purpose: This study was aimed to examine the effectiveness of Salvadora persica in several modified preparation against the salivary Streptoccocus mutans and Lactobacilli. Methods: A single-blind, randomized clinical trial study with crossover design was used. The study comprised of 5 groups, per group consisted of 14 healthy dental students who had good oral hygiene. Each participant was given 5 intervention to clean their teeth using, electric toothbrush modified with siwak, electric toothbrush with siwak toothpaste (colgate kayu sugi toothpaste, electric toothbrush with general toothpaste (colgate total toothpaste, original siwak chewing stick and normal saline. The wash out periode each intervention was 3 days. Patients’ saliva was used to quantify the levels of Streptococcus mutans and Lactobacilli using caries risk test (CRT kit from Vivadent. Results: The results showed that there was a reduction in Streptococcus mutans and Lactobacilli risk score after cleansing different intervention except electric toothbrush modified with siwak. However, there was no significant difference for Streptococcus mutans (p=0.158 and Lactobacilli (p=0.396 risk score reduction when comparison was done between the groups. Conclusion: The original siwak chewing stick has antimicrobial effects similar to toothbrushing with general toothpaste and salvadora persica toothpaste. However, electric toothbrush modified with siwak has no effect on microbial reduction.Latar belakang: Salvadora persica adalah pembersih gigi tradisional yang lebih dikenal dengan sebutan Siwak. Beberapa penelitian menunjukkan bahwa Salvadora persica memiliki daya antibakteri. Tujuan: Penelitian ini bertujuan untuk mengetahui efektivitas Salvadora persica dalam berbagai bentuk sediaan untuk membersihkan

Seed dormancy and germination

NARCIS (Netherlands)

Bentsink, L.; Koornneef, M.

2002-01-01

Arabidopsis possesses dormancy, as is the case for many other plant species, which is controlled by environmental factors such as light, temperature and time of dry storage as well as by genetic factors. The use of genetics and molecular genetics in Arabidopsis is starting to shed light on some

Anatomy of Phyllodina persica (Bivalvia: Tellinidae, and its first occurrence in southeastern Brazilian waters

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Rodrigo Cesar Marques

2013-01-01

Full Text Available This study presents a detailed anatomy of a rare Western Atlantic tellin, Phyllodina persica, under a comparative scenario. Some characters are shared with other tellinids such as the large hemipalps compared to gills; gills with outer demibranch with a single lamella absent from the pericardial region; the type-V stomach associated with the style sac conjoined with the proximal intestine, and distal intestine presenting a dorsal and ventral group of loops, separated by the transverse muscle. The stomach presents a laterally enlarged typhlosole, although shallow, without flange in the margins. This feature is not found in other tellinid species. Another noteworthy feature in the stomach is the aperture of both caeca, which are larger than the left pouch aperture, and as wide as the style sac aperture. Furthermore, there is an interesting small process in the anterior hinge, and a pair of oblique protractor muscles placed posteriorly to the anterior foot retractor muscle, being a new type of intrinsic muscle described in bivalves. In addition to anatomy, this study presents the southernmost record of P. persica, expanding its distribution to the southeastern region of Brazil.

Profiling the Proteome of Mycobacterium tuberculosis during Dormancy and Reactivation*

Science.gov (United States)

Gopinath, Vipin; Raghunandanan, Sajith; Gomez, Roshna Lawrence; Jose, Leny; Surendran, Arun; Ramachandran, Ranjit; Pushparajan, Akhil Raj; Mundayoor, Sathish; Jaleel, Abdul; Kumar, Ramakrishnan Ajay

2015-01-01

Tuberculosis, caused by Mycobacterium tuberculosis, still remains a major global health problem. The main obstacle in eradicating this disease is the ability of this pathogen to remain dormant in macrophages, and then reactivate later under immuno-compromised conditions. The physiology of hypoxic nonreplicating M. tuberculosis is well-studied using many in vitro dormancy models. However, the physiological changes that take place during the shift from dormancy to aerobic growth (reactivation) have rarely been subjected to a detailed investigation. In this study, we developed an in vitro reactivation system by re-aerating the virulent laboratory strain of M. tuberculosis that was made dormant employing Wayne's dormancy model, and compared the proteome profiles of dormant and reactivated bacteria using label-free one-dimensional LC/MS/MS analysis. The proteome of dormant bacteria was analyzed at nonreplicating persistent stage 1 (NRP1) and stage 2 (NRP2), whereas that of reactivated bacteria was analyzed at 6 and 24 h post re-aeration. Proteome of normoxially grown bacteria served as the reference. In total, 1871 proteins comprising 47% of the M. tuberculosis proteome were identified, and many of them were observed to be expressed differentially or uniquely during dormancy and reactivation. The number of proteins detected at different stages of dormancy (764 at NRP1, 691 at NRP2) and reactivation (768 at R6 and 983 at R24) was very low compared with that of the control (1663). The number of unique proteins identified during normoxia, NRP1, NRP2, R6, and R24 were 597, 66, 56, 73, and 94, respectively. We analyzed various biological functions during these conditions. Fluctuation in the relative quantities of proteins involved in energy metabolism during dormancy and reactivation was the most significant observation we made in this study. Proteins that are up-regulated or uniquely expressed during reactivation from dormancy offer to be attractive targets for therapeutic

Evaluation of different methods to overcome in vitro seed dormancy ...

African Journals Online (AJOL)

SAM

2014-09-03

Sep 3, 2014 ... Seeds from yellow passion fruit (Passiflora edulis Sims) present dormancy imposed by the seed-coat. The present study aimed to evaluate some methods to overcome dormancy of seeds from P. edulis grown under in vitro conditions. The experimental design was completely randomized in factorial scheme ...

Comparison of two culture media for breaking seed dormancy and ...

African Journals Online (AJOL)

... the percentage germination and days to germination in each of the four species were higher and faster in water with agar medium in comparison to MS growth medium. These results suggest that the Linum seeds have exogenous and endogenous dormancy. Key words: Dormancy, germination, MS media, Linum species, ...

A remarkable synergistic effect at the transcriptomic level in peach fruits doubly infected by prunus necrotic ringspot virus and peach latent mosaic viroid.

Science.gov (United States)

Herranz, Mari Carmen; Niehl, Annette; Rosales, Marlene; Fiore, Nicola; Zamorano, Alan; Granell, Antonio; Pallas, Vicente

2013-05-28

Microarray profiling is a powerful technique to investigate expression changes of large amounts of genes in response to specific environmental conditions. The majority of the studies investigating gene expression changes in virus-infected plants are limited to interactions between a virus and a model host plant, which usually is Arabidopsis thaliana or Nicotiana benthamiana. In the present work, we performed microarray profiling to explore changes in the expression profile of field-grown Prunus persica (peach) originating from Chile upon single and double infection with Prunus necrotic ringspot virus (PNRSV) and Peach latent mosaic viroid (PLMVd), worldwide natural pathogens of peach trees. Upon single PLMVd or PNRSV infection, the number of statistically significant gene expression changes was relatively low. By contrast, doubly-infected fruits presented a high number of differentially regulated genes. Among these, down-regulated genes were prevalent. Functional categorization of the gene expression changes upon double PLMVd and PNRSV infection revealed protein modification and degradation as the functional category with the highest percentage of repressed genes whereas induced genes encoded mainly proteins related to phosphate, C-compound and carbohydrate metabolism and also protein modification. Overrepresentation analysis upon double infection with PLMVd and PNRSV revealed specific functional categories over- and underrepresented among the repressed genes indicating active counter-defense mechanisms of the pathogens during infection. Our results identify a novel synergistic effect of PLMVd and PNRSV on the transcriptome of peach fruits. We demonstrate that mixed infections, which occur frequently in field conditions, result in a more complex transcriptional response than that observed in single infections. Thus, our data demonstrate for the first time that the simultaneous infection of a viroid and a plant virus synergistically affect the host transcriptome in

Physicochemical characterisation of four cherry species (Prunus spp.) grown in China.

Science.gov (United States)

Cao, Jinping; Jiang, Qing; Lin, Juanying; Li, Xian; Sun, Chongde; Chen, Kunsong

2015-04-15

The physicochemical characteristics of four cherry species (Prunus avium, Prunus cerasus, Prunus pseudocerasus and Prunus tomentosa) were evaluated. Inter-species variability was greater than intra-species differences. Glucose and fructose were the main sugars, and malic acid was the main organic acid in all species. Combining HPLC-DAD and LC-ESI-MS/MS technologies, total 25 phenolic components were preliminarily identified. P. avium was characterised by high fruit weight, edible proportion, sugar content and low acid content, which made it suitable for fresh eating. P. cerasus was high in acid content and anthocyanins content, making it a good processing species. P. pseudocerasus had rich flavonols varieties and high proportion of hydrocinnamic acids. P. tomentosa was characterised by high total phenolics content (especially flavonols and tannins) and antioxidant activity, indicating a great developmental potential as a health fruit. The results of the present study might provide theoretical guidance for the further development and utilisation of cherries. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antioxidant capacity of chewing stick miswak Salvadora persica

OpenAIRE

Mohamed, Saleh A; Khan, Jalaluddin A

2013-01-01

Background Chewing stick (miswak Salvadora persica L.) is an effective tool for oral hygiene. It possessed various biological properties including significant antibacterial and anti-fungal effects. In the present study, we evaluated the antioxidant compounds in miswak. Method Miswak root was extracted with 80% methanol. Methanol extract as antioxidant was evaluated by using DPPH, ABTS and phosphomolybdenum complex assays and analysis by GC-MS. Peroxidase, catalase and polyphenoloxidase assays...

Spatially heterogeneous stochasticity and the adaptive diversification of dormancy.

Science.gov (United States)

Rajon, E; Venner, S; Menu, F

2009-10-01

Diversified bet-hedging, a strategy that leads several individuals with the same genotype to express distinct phenotypes in a given generation, is now well established as a common evolutionary response to environmental stochasticity. Life-history traits defined as diversified bet-hedging (e.g. germination or diapause strategies) display marked differences between populations in spatial proximity. In order to find out whether such differences can be explained by local adaptations to spatially heterogeneous environmental stochasticity, we explored the evolution of bet-hedging dormancy strategies in a metapopulation using a two-patch model with patch differences in stochastic juvenile survival. We found that spatial differences in the level of environmental stochasticity, restricted dispersal, increased fragmentation and intermediate survival during dormancy all favour the adaptive diversification of bet-hedging dormancy strategies. Density dependency also plays a major role in the diversification of dormancy strategies because: (i) it may interact locally with environmental stochasticity and amplify its effects; however, (ii) it can also generate chaotic population dynamics that may impede diversification. Our work proposes new hypotheses to explain the spatial patterns of bet-hedging strategies that we hope will encourage new empirical studies of this topic.

Dynamics of Membrane Potential Variation and Gene Expression Induced by Spodoptera littoralis, Myzus persicae, and Pseudomonas syringae in Arabidopsis

Science.gov (United States)

Bricchi, Irene; Bertea, Cinzia M.; Occhipinti, Andrea; Paponov, Ivan A.; Maffei, Massimo E.

2012-01-01

Background Biotic stress induced by various herbivores and pathogens invokes plant responses involving different defense mechanisms. However, we do not know whether different biotic stresses share a common response or which signaling pathways are involved in responses to different biotic stresses. We investigated the common and specific responses of Arabidopsis thaliana to three biotic stress agents: Spodoptera littoralis, Myzus persicae, and the pathogen Pseudomonas syringae. Methodology/Principal Findings We used electrophysiology to determine the plasma membrane potential (Vm) and we performed a gene microarray transcriptome analysis on Arabidopsis upon either herbivory or bacterial infection. Vm depolarization was induced by insect attack; however, the response was much more rapid to S. littoralis (30 min −2 h) than to M. persicae (4–6 h). M. persicae differentially regulated almost 10-fold more genes than by S. littoralis with an opposite regulation. M. persicae modulated genes involved in flavonoid, fatty acid, hormone, drug transport and chitin metabolism. S. littoralis regulated responses to heat, transcription and ion transport. The latest Vm depolarization (16 h) was found for P. syringae. The pathogen regulated responses to salicylate, jasmonate and to microorganisms. Despite this late response, the number of genes differentially regulated by P. syringae was closer to those regulated by S. littoralis than by M. persicae. Conclusions/Significance Arabidopsis plasma membranes respond with a Vm depolarization at times depending on the nature of biotic attack which allow setting a time point for comparative genome-wide analysis. A clear relationship between Vm depolarization and gene expression was found. At Vm depolarization timing, M. persicae regulates a wider array of Arabidopsis genes with a clear and distinct regulation than S. littoralis. An almost completely opposite regulation was observed between the aphid and the pathogen, with the former

Maturation, temperature and breaking dormancy of Comanthera seeds

OpenAIRE

Andréa Santos Oliveira; Maria Laene Moreira Carvalho; Cláudio das Neves Vieira Bárbara; Tanismare Tatiana Almeida; Marcela Carlota Nery

2016-01-01

Given the importance of “everlasting” plants for their ornamental value and vulnerability to extractive practices, studies to ensure the propagation of the species are indispensable. The aim of this study was to assess whether there is an association between seed coat color and the quality of everlasting seeds, in the presence or absence of dormancy. Four species (Comanthera elegans, C. nitida, C. bisculata, and Comanthera sp.) were separated with respect to seed coat color and underwent germ...

Proteome analysis of Norway maple (Acer platanoides L.) seeds dormancy breaking and germination: influence of abscisic and gibberellic acids.

Science.gov (United States)

Pawłowski, Tomasz A

2009-05-04

Seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid) and growth promoters (e.g. gibberellins) is the main cause of seed dormancy breaking. Differences in the status of hormones would affect expression of genes required for germination. Proteomics offers the opportunity to examine simultaneous changes and to classify temporal patterns of protein accumulation occurring during seed dormancy breaking and germination. Analysis of the functions of the identified proteins and the related metabolic pathways, in conjunction with the plant hormones implicated in seed dormancy breaking, would expand our knowledge about this process. A proteomic approach was used to analyse the mechanism of dormancy breaking in Norway maple seeds caused by cold stratification, and the participation of the abscisic (ABA) and gibberellic (GA) acids. Forty-four proteins showing significant changes were identified by mass spectrometry. Of these, eight spots were identified as water-responsive, 18 spots were ABA- and nine GA-responsive and nine spots were regulated by both hormones. The classification of proteins showed that most of the proteins associated with dormancy breaking in water were involved in protein destination. Most of the ABA- and GA-responsive proteins were involved in protein destination and energy metabolism. In this study, ABA was found to mostly down-regulate proteins whereas GA up-regulated proteins abundance. Most of the changes were observed at the end of stratification in the germinated seeds. This is the most active period of dormancy breaking when seeds pass from the quiescent state to germination. Seed dormancy breaking involves

Proteome analysis of Norway maple (Acer platanoides L. seeds dormancy breaking and germination: influence of abscisic and gibberellic acids

Directory of Open Access Journals (Sweden)

Pawłowski Tomasz A

2009-05-01

Full Text Available Abstract Background Seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid and growth promoters (e.g. gibberellins is the main cause of seed dormancy breaking. Differences in the status of hormones would affect expression of genes required for germination. Proteomics offers the opportunity to examine simultaneous changes and to classify temporal patterns of protein accumulation occurring during seed dormancy breaking and germination. Analysis of the functions of the identified proteins and the related metabolic pathways, in conjunction with the plant hormones implicated in seed dormancy breaking, would expand our knowledge about this process. Results A proteomic approach was used to analyse the mechanism of dormancy breaking in Norway maple seeds caused by cold stratification, and the participation of the abscisic (ABA and gibberellic (GA acids. Forty-four proteins showing significant changes were identified by mass spectrometry. Of these, eight spots were identified as water-responsive, 18 spots were ABA- and nine GA-responsive and nine spots were regulated by both hormones. The classification of proteins showed that most of the proteins associated with dormancy breaking in water were involved in protein destination. Most of the ABA- and GA-responsive proteins were involved in protein destination and energy metabolism. Conclusion In this study, ABA was found to mostly down-regulate proteins whereas GA up-regulated proteins abundance. Most of the changes were observed at the end of stratification in the germinated seeds. This is the most active period of dormancy breaking when seeds pass from the quiescent

Use of silicon as inductor of the resistance in potato to Myzus persicae (Sulzer) (Hemiptera: Aphididae); Uso de silicio como indutor de resistencia em batata a Myzus persicae (Sulzer) (Hemiptera: Aphididae)

Energy Technology Data Exchange (ETDEWEB)

Gomes, Flavia B.; Moraes, Jair C.; Antunes, Cristiana [Universidade Federal de Lavras, MG (Brazil). Dept. de Entomologia; Santos, Custodio D. dos [Universidade Federal de Lavras, MG (Brazil). Dept. de Quimica

2008-03-15

The aphid Myzus persicae (Sulzer) is an important pest of potato and causes direct harm, due to the quantity of sap extracted and for being vector of important phytovirus. This work was carried out to evaluate the action of silicon as a resistance inducer of potato to M. persicae. Four treatments were tried: foliar fertilization with silicon acid at 1%; soil fertilization with 250 ml silicic acid solution at 1%; foliar fertilization with silicon acid at 1% + soil fertilization with 250 ml silicic acid solution at 1%; and a control. The treatments were applied thirty days after the explants emergence. Fifteen days after the application of the treatments, feeding preference and some biological aspects of the aphids were evaluated. After, the content of tannins and lignin present in the leaves and the activity of the enzymes peroxidase and phenylalanine ammonia-lyase were also determined. The silicon fertilization did not affect the preference of the aphids; however it reduced fecundity and the rate of population growth of the insects. The lignin percentage increased in the leaves of plants fertilized with silicon via soil and/or foliar and the percentage of tannins increased only in the leaves fertilized via soil plus foliar. The silicon acted as a resistance inducer to M. persicae in potato. (author)

Characterization of New Isolates of Apricot vein clearing-associated virus and of a New Prunus-Infecting Virus: Evidence for Recombination as a Driving Force in Betaflexiviridae Evolution.

Directory of Open Access Journals (Sweden)

Armelle Marais

Full Text Available Double stranded RNAs from Prunus samples gathered from various surveys were analyzed by a deep-sequencing approach. Contig annotations revealed the presence of a potential new viral species in an Azerbaijani almond tree (Prunus amygdalus and its genome sequence was completed. Its genomic organization is similar to that of the recently described Apricot vein clearing associated virus (AVCaV for which two new isolates were also characterized, in a similar fashion, from two Japanese plums (Prunus salicina from a French germplasm collection. The amino acid identity values between the four proteins encoded by the genome of the new virus have identity levels with those of AVCaV which fall clearly outside the species demarcation criteria. The new virus should therefore be considered as a new species for which the name of Caucasus prunus virus (CPrV has been proposed. Phylogenetic relationships and nucleotide comparisons suggested that together with AVCaV, CPrV could define a new genus (proposed name: Prunevirus in the family Betaflexiviridae. A molecular test targeting both members of the new genus was developed, allowing the detection of additional AVCaV isolates, and therefore extending the known geographical distribution and the host range of AVCaV. Moreover, the phylogenetic trees reconstructed with the amino acid sequences of replicase, movement and coat proteins of representative Betaflexiviridae members suggest that Citrus leaf blotch virus (CLBV, type member of the genus Citrivirus may have evolved from a recombination event involving a Prunevirus, further highlighting the importance of recombination as a driving force in Betaflexiviridae evolution. The sequences reported in the present manuscript have been deposited in the GenBank database under accession numbers KM507061-KM504070.

Key genes involved in desiccation tolerance and dormancy across life forms

NARCIS (Netherlands)

Costa, M.C.D.; Farrant, Jill M.; Oliver, Melvin J.; Ligterink, Wilco; Buitink, Julia; Hilhorst, H.M.W.

2016-01-01

Desiccation tolerance (DT, the ability of certain organisms to survive severe dehydration) was a key trait in the evolution of life in terrestrial environments. Likely, the development of desiccation-tolerant life forms was accompanied by the acquisition of dormancy or a dormancy-like stage as a

Bud Dormancy in Perennial Fruit Tree Species: A Pivotal Role for Oxidative Cues

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Rémi Beauvieux

2018-05-01

Full Text Available For perennial plants, bud dormancy is a crucial step as its progression over winter determines the quality of bud break, flowering, and fruiting. In the past decades, many studies, based on metabolic, physiological, subcellular, genetic, and genomic analyses, have unraveled mechanisms underlying bud dormancy progression. Overall, all the pathways identified are interconnected in a very complex manner. Here, we review early and recent findings on the dormancy processes in buds of temperate fruit trees species including hormonal signaling, the role of plasma membrane, carbohydrate metabolism, mitochondrial respiration and oxidative stress, with an effort to link them together and emphasize the central role of reactive oxygen species accumulation in the control of dormancy progression.

Mechanisms of seed dormancy in an annual population of Zostera marina (eelgrass) from the Netherlands)

NARCIS (Netherlands)

Harrison, P.G.

1991-01-01

Mechanisms of dormancy of seeds from an annual population of the seagrass Zostera marina L. (eelgrass) in the SW Netherlands were investigated in the laboratory. Both physiological dormancy (a requirement for reduced salinity for germination) and physical dormancy (imposed by the seed coat) existed

Involvement of ABA in induction of secondary dormancy in barley (Hordeum vulgare L.) seeds.

Science.gov (United States)

Leymarie, Juliette; Robayo-Romero, Maria Emilia; Gendreau, Emmanuel; Benech-Arnold, Roberto L; Corbineau, Françoise

2008-12-01

At harvest, barley seeds are dormant because their germination is difficult above 20 degrees C. Incubation of primary dormant seeds at 30 degrees C, a temperature at which they do not germinate, results in a loss of their ability to germinate at 20 degrees C. This phenomenon which corresponds to an induction of a secondary dormancy is already observed after a pre-treatment at 30 degrees C as short as 4-6 h, and is optimal after 24-48 h. It is associated with maintenance of a high level of embryo ABA content during seed incubation at 30 degrees C, and after seed transfer at 20 degrees C, while ABA content decreases rapidly in embryos of primary dormant seeds placed directly at 20 degrees C. Induction of secondary dormancy also results in an increase in embryo responsiveness to ABA at 20 degrees C. Application of ABA during seed treatment at 30 degrees C has no significant additive effect on the further germination at 20 degrees C. In contrast, incubation of primary dormant seeds at 20 degrees C for 48 and 72 h in the presence of ABA inhibits further germination on water similarly to 24-48 h incubation at 30 degrees C. However fluridone, an inhibitor of ABA synthesis, applied during incubation of the grains at 30 degrees C has only a slight effect on ABA content and secondary dormancy. Expression of genes involved in ABA metabolism (HvABA8'OH-1, HvNCED1 and HvNCED2) was studied in relation to the expression of primary and secondary dormancies. The results presented suggest a specific role for HvNCED1 and HvNCED2 in regulation of ABA synthesis in secondary seed dormancy.

Seed dormancy and seed longevity: from genetic variation to gene identification

NARCIS (Netherlands)

Nguyen, T.P.

2014-01-01

Seed dormancy and seed longevity are the most important survival traits in the soil seed bank. Both traits are induced during seed maturation and evolved to assure seed survival during environmental conditions that cannot support the regular course of life. Seed dormancy is related to the timing of

Transcriptome and Metabolite Changes during Hydrogen Cyanamide-Induced Floral Bud Break in Sweet Cherry.

Science.gov (United States)

Ionescu, Irina A; López-Ortega, Gregorio; Burow, Meike; Bayo-Canha, Almudena; Junge, Alexander; Gericke, Oliver; Møller, Birger L; Sánchez-Pérez, Raquel

2017-01-01

Release of bud dormancy in perennial woody plants is a temperature-dependent process and thus flowering in these species is heavily affected by climate change. The lack of cold winters in temperate growing regions often results in reduced flowering and low fruit yields. This is likely to decrease the availability of fruits and nuts of the Prunus spp. in the near future. In order to maintain high yields, it is crucial to gain detailed knowledge on the molecular mechanisms controlling the release of bud dormancy. Here, we studied these mechanisms using sweet cherry ( Prunus avium L.), a crop where the agrochemical hydrogen cyanamide (HC) is routinely used to compensate for the lack of cold winter temperatures and to induce flower opening. In this work, dormant flower buds were sprayed with hydrogen cyanamide followed by deep RNA sequencing, identifying three main expression patterns in response to HC. These transcript level results were validated by quantitative real time polymerase chain reaction and supported further by phytohormone profiling (ABA, SA, IAA, CK, ethylene, JA). Using these approaches, we identified the most up-regulated pathways: the cytokinin pathway, as well as the jasmonate and the hydrogen cyanide pathway. Our results strongly suggest an inductive effect of these metabolites in bud dormancy release and provide a stepping stone for the characterization of key genes in bud dormancy release.

Transcriptome and Metabolite Changes during Hydrogen Cyanamide-Induced Floral Bud Break in Sweet Cherry

Directory of Open Access Journals (Sweden)

Irina A. Ionescu

2017-07-01

Full Text Available Release of bud dormancy in perennial woody plants is a temperature-dependent process and thus flowering in these species is heavily affected by climate change. The lack of cold winters in temperate growing regions often results in reduced flowering and low fruit yields. This is likely to decrease the availability of fruits and nuts of the Prunus spp. in the near future. In order to maintain high yields, it is crucial to gain detailed knowledge on the molecular mechanisms controlling the release of bud dormancy. Here, we studied these mechanisms using sweet cherry (Prunus avium L., a crop where the agrochemical hydrogen cyanamide (HC is routinely used to compensate for the lack of cold winter temperatures and to induce flower opening. In this work, dormant flower buds were sprayed with hydrogen cyanamide followed by deep RNA sequencing, identifying three main expression patterns in response to HC. These transcript level results were validated by quantitative real time polymerase chain reaction and supported further by phytohormone profiling (ABA, SA, IAA, CK, ethylene, JA. Using these approaches, we identified the most up-regulated pathways: the cytokinin pathway, as well as the jasmonate and the hydrogen cyanide pathway. Our results strongly suggest an inductive effect of these metabolites in bud dormancy release and provide a stepping stone for the characterization of key genes in bud dormancy release.

TBK1 Regulates Prostate Cancer Dormancy through mTOR Inhibition

Directory of Open Access Journals (Sweden)

Jin Koo Kim

2013-09-01

Full Text Available The mechanisms that regulate hematopoietic stem cell (HSC dormancy and self-renewal are well established and are largely dependent on signals emanating from the HSC niche. Recently, we found that prostate cancer (PCa cells target the HSC niche in mouse bone marrow (BM during metastasis. Little is known, however, as to how the HSC niche may regulate dormancy in cancer cells. In this study, we investigated the effects of TANK binding kinase 1 (TBK1 on PCa dormancy in the BM niche. We found that binding with niche osteoblasts induces the expression of TBK1 in PCa cells PC3 and C4-2B. Interestingly, TBK1 interacts with mammalian target of rapamycin (mTOR and inhibits its function. Rapamycin, an mTOR inhibitor, induces cell cycle arrest of PCa cells and enhances chemotherapeutic resistance of PCa cells. As a result, the knockdown of TBK1 decreases PCa stem-like cells and drug resistance in vitro and in vivo. Taken together, these results strongly indicate that TBK1 plays an important role in the dormancy and drug resistance of PCa.

Effects of dormancy-breaking chemicals on ABA levels in barley grain embryos

NARCIS (Netherlands)

Wang, M.; Meulen, R.M. van der; Visser, K.; Schalk, H.P. van; Duijn, B. van; Boer, A.H. de

1998-01-01

The endogenous ABA contents of dormant and nondormant barley grains were determined following application of different compounds to break dormancy. The chemicals used for breaking of dormancy in intact dormant grains were weak and strong acids, alcohols,. hydrogen peroxide, cyanide, nitrate,

Integrated transcriptomic and proteomic profiling of white spruce stems during the transition from active growth to dormancy.

Science.gov (United States)

Galindo González, Leonardo M; El Kayal, Walid; Ju, Chelsea J-T; Allen, Carmen C G; King-Jones, Susanne; Cooke, Janice E K

2012-04-01

In the autumn, stems of woody perennials such as forest trees undergo a transition from active growth to dormancy. We used microarray transcriptomic profiling in combination with a proteomics analysis to elucidate processes that occur during this growth-to-dormancy transition in a conifer, white spruce (Picea glauca[Moench] Voss). Several differentially expressed genes were likely associated with the developmental transition that occurs during growth cessation in the cambial zone and the concomitant completion of cell maturation in vascular tissues. Genes encoding for cell wall and membrane biosynthetic enzymes showed transcript abundance patterns consistent with completion of cell maturation, and also of cell wall and membrane modifications potentially enabling cells to withstand the harsh conditions of winter. Several differentially expressed genes were identified that encoded putative regulators of cambial activity, cell development and of the photoperiodic pathway. Reconfiguration of carbon allocation figured centrally in the tree's overwintering preparations. For example, genes associated with carbon-based defences such as terpenoids were down-regulated, while many genes associated with protein-based defences and other stress mitigation mechanisms were up-regulated. Several of these correspond to proteins that were accumulated during the growth-to-dormancy transition, emphasizing the importance of stress protection in the tree's adaptive response to overwintering. © 2011 Blackwell Publishing Ltd.

Self-incompatibility of Prunus tenella and evidence that reproductively isolated species of Prunus have different SFB alleles coupled with an identical S-RNase allele.

Science.gov (United States)

Surbanovski, Nada; Tobutt, Kenneth R; Konstantinović, Miroslav; Maksimović, Vesna; Sargent, Daniel J; Stevanović, Vladimir; Bosković, Radovan I

2007-05-01

Many species of Prunus display an S-RNase-based gametophytic self-incompatibility (SI), controlled by a single highly polymorphic multigene complex termed the S-locus. This comprises tightly linked stylar- and pollen-expressed genes that determine the specificity of the SI response. We investigated SI of Prunus tenella, a wild species found in small, isolated populations on the Balkan peninsula, initially by pollination experiments and identifying stylar-expressed RNase alleles. Nine P. tenella S-RNase alleles (S(1)-S(9)) were cloned; their sequence analysis showed a very high ratio of non-synonymous to synonymous nucleotide substitutions (K(a)/K(s)) and revealed that S-RNase alleles of P. tenella, unlike those of Prunus dulcis, show positive selection in all regions except the conserved regions and that between C2 and RHV. Remarkably, S(8)-RNase, was found to be identical to S(1)-RNase from Prunus avium, a species that does not interbreed with P. tenella and, except for just one amino acid, to S(11) of P. dulcis. However, the corresponding introns and S-RNase-SFB intergenic regions showed considerable differences. Moreover, protein sequences of the pollen-expressed SFB alleles were not identical, harbouring 12 amino-acid replacements between those of P. tenella SFB(8) and P. avium SFB(1). Implications of this finding for hypotheses about the evolution of new S-specificities are discussed.

FEATURES OF THE SEED DORMANCY IN UMBELLIFER CROPS CAUSED BY VARIOUS FACTORS

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D. N. Baleev

2017-01-01

Full Text Available Experiments were carried out at FGBNU VNIIO in 20112016. The aim of the study was to analyze the influence of different types of organic dormancy caused by various factors on seed quality of some representatives of umbellifer crops. The objects of the study were seeds: parsnip ‘Kulinar’ (Pastinaca sativa L.; carrot ‘Rogneda’ (Daucus carrota L.; root parsley ‘Ljubasha’ (Petroselinum crispum (Mill. Nyman ex A.W. Hill.; root celery ‘Kupidon’ (Apium graveolens L.; coriander ‘Yantar’ (Coriandrum sativum L. and dill ‘Kentavr’ (Anethum graveolens L.. In all seeds studied, the speed of embryo growth was decreased by 30% or0.03 mma day. Under influence of the induced dormancy caused by incubation in extract from dill seeds, the speed of embryo growth in all species was decreased by 94-97% on average. The process of germination of just picked seeds in all crops studied showed itself in reduction of germinated seed number by 54% as compared with control variant. Under the effect of incubation at high temperature the seeds of parsnip and root celery didn’t germinate, whereas the germination in the seeds of coriander, root parsley and carrot was decreased by 51%, 47% and 46%, respectively as compared with control. There is no germination observed in parsnip, carrot, root celery and coriander under influence of induced dormancy caused by incubation in extract from dill seeds. In this case, the germination of seeds of root parsley and dill was 8.1% and 15%, respectively. The Pearson correlation between the speed of embryo growth and percent of seed germination showed the significant and positive relationship in the range 0.706-0.952. Analysis of variance (ANOVA showed that induced by temperature or allelopathic dormancy had impact on the speed of embryo’s growth in the crops studied, where factor effect was 89-86% depending on type of dormancy. Analysis of variance between the factors of dormancy and germination revealed that all

Analysis of the embryo proteome of sycamore (Acer pseudoplatanus L.) seeds reveals a distinct class of proteins regulating dormancy release.

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Pawłowski, Tomasz Andrzej; Staszak, Aleksandra Maria

2016-05-20

Acer pseudoplatanus seeds are characterized by a deep physiological embryo dormancy that requires a few weeks of cold stratification in order to promote germination. Understanding the function of proteins and their related metabolic pathways, in conjunction with the plant hormones implicated in the breaking of seed dormancy, would expand our knowledge pertaining to this process. In this study, a proteomic approach was used to analyze the changes occurring in seeds in response to cold stratification, which leads to dormancy release. In addition, the involvement of abscisic (ABA) and gibberellic acids (GA) was also examined. Fifty-three proteins showing significant changes were identified by mass spectrometry. An effect of ABA on protein variation was observed at the beginning of stratification, while the influence of GA on protein abundance was observed during the middle phase of stratification. The majority of proteins associated with dormancy breaking in the presence of only water, and also ABA or GA, were classified as being involved in metabolism and genetic information processing. For metabolic-related proteins, the effect of ABA on protein abundance was stimulatory for half of the proteins and inhibitory for half of the proteins. On the other hand, the effect on genetic information processing related proteins was stimulatory. GA was found to upregulate both metabolic-related and genetic information processing-related proteins. While seed dormancy breaking depends on proteins involved in a variety of processes, proteins associated with methionine metabolism (adenosine kinase, methionine synthase) and glycine-rich RNA binding proteins appear to be of particular importance. Copyright © 2016 Elsevier GmbH. All rights reserved.

Chemical composition and antibacterial properties of essential oil and fatty acids of different parts of Ligularia persica Boiss.

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Mohadjerani, Maryam; Hosseinzadeh, Rahman; Hosseini, Maryam

2016-01-01

The objective of this research was to investigate the chemical composition and antibacterial activities of the fatty acids and essential oil from various parts of Ligularia persica Boiss (L. persica) growing wild in north of Iran. Essential oils were extracted by using Clevenger-type apparatus. Antibacterial activity was tested on two Gram-positive and two Gram-negative bacteria by using micro dilution method. GC and GC∕MS analysis of the oils resulted in detection of 94%, 96%, 93%, 99% of the total essential oil of flowers, stems, roots and leaves, respectively. The main components of flowers oil were cis-ocimene (15.4%), β-myrcene (4.4%), β-ocimene (3.9%), and γ-terpinene (5.0%). The major constituents of stems oil were β-phellandrene (5.4%), β-cymene (7.0%), valencene (3.9%). The main compounds of root oil were fukinanolid (17.0%), α-phellandrene (11.5%) and Β-selinene (5.0%) and in the case of leaves oil were cis-ocimene (4.8%), β-ocimene (4.9%), and linolenic acid methyl ester (4.7%). An analysis by GC-FID and GC-MS on the fatty-acid composition of the different parts of L. persica showed that major components were linoleic acid (11.3-31.6%), linolenic acid (4.7-21.8%) and palmitic acid (7.2-23.2%). Saturated fatty acids were found in lower amounts than unsaturated ones. The least minimum inhibition concentration (MIC) of the L. persica was 7.16 μg/ml against Pseudomonas aeruginosa. Our study indicated that the essential oil from L. persica stems and flowers showed high inhibitory effect on the Gram negative bacteria. The results also showed that fatty acids from the stems and leaves contained a high amount of poly-unsaturated fatty acids (PUFAs).

Considering Intermittent Dormancy in an Advanced Life Support Systems Architecture

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Sargusingh, Miriam J.; Perry, Jay L.

2017-01-01

Many advanced human space exploration missions being considered by the National Aeronautics and Space Administration (NASA) include concepts in which in-space systems cycle between inhabited and uninhabited states. Managing the life support system (LSS) may be particularly challenged during these periods of intermittent dormancy. A study to identify LSS management challenges and considerations relating to dormancy is described. The study seeks to define concepts suitable for addressing intermittent dormancy states and to evaluate whether the reference LSS architectures being considered by the Advanced Exploration Systems (AES) Life Support Systems Project (LSSP) are sufficient to support this operational state. The primary focus of the study is the mission concept considered to be the most challenging-a crewed Mars mission with an extensive surface stay. Results from this study are presented and discussed.

Representing Microbial Dormancy in Soil Decomposition Models Improves Model Performance and Reveals Key Ecosystem Controls on Microbial Activity

Science.gov (United States)

He, Y.; Yang, J.; Zhuang, Q.; Wang, G.; Liu, Y.

2014-12-01

Climate feedbacks from soils can result from environmental change and subsequent responses of plant and microbial communities and nutrient cycling. Explicit consideration of microbial life history traits and strategy may be necessary to predict climate feedbacks due to microbial physiology and community changes and their associated effect on carbon cycling. In this study, we developed an explicit microbial-enzyme decomposition model and examined model performance with and without representation of dormancy at six temperate forest sites with observed soil efflux ranged from 4 to 10 years across different forest types. We then extrapolated the model to all temperate forests in the Northern Hemisphere (25-50°N) to investigate spatial controls on microbial and soil C dynamics. Both models captured the observed soil heterotrophic respiration (RH), yet no-dormancy model consistently exhibited large seasonal amplitude and overestimation in microbial biomass. Spatially, the total RH from temperate forests based on dormancy model amounts to 6.88PgC/yr, and 7.99PgC/yr based on no-dormancy model. However, no-dormancy model notably overestimated the ratio of microbial biomass to SOC. Spatial correlation analysis revealed key controls of soil C:N ratio on the active proportion of microbial biomass, whereas local dormancy is primarily controlled by soil moisture and temperature, indicating scale-dependent environmental and biotic controls on microbial and SOC dynamics. These developments should provide essential support to modeling future soil carbon dynamics and enhance the avenue for collaboration between empirical soil experiment and modeling in the sense that more microbial physiological measurements are needed to better constrain and evaluate the models.

Effect of Different Dormancy Breaking Treatments on Seed Germination of Salsifis (Teragopogon collinus and Flixweed ( Descurainia Sophia as Two Weed Species

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marzie mazhari

2017-01-01

Full Text Available Introduction: Weeds limit crops growth, development and yield through adjacency and competing and seed dormancy is a problem in controlling of weeds. Man has been always tried to optimize crop yield through weeds controlling. Weeds seed bank in the soil can affected weed management and their control methods. So identifying seed bank characters has important role in choice of management methods in seeds of many plant species which cannot germinate despite favorable environmental conditions. Main reasons for this problem, which is termed as seed dormancy, are hard and impermeable seed coat and presence of immature or dormant embryo. To break dormancy, a variety of methods are in vogue worldwide these days. Of all different methods of breaking dormancy, treatment of seed with certain chemicals including different types of plant growth regulators (PGRs is contemplated as the most effective one. Gibberellic acid (GA3 is the most widely used PGR to improve seed germination in different plant species. Also, nitrate (such as KNO3 clearly stimulates the germination of dormant seeds. KNO3 is the most widely used chemical for promoting germination. Solutions of KNO3 are common in routine germination testing and are recommended by the Association of Official Seed Analysts and the International Seed Testing Association (ISTA for germination tests of many species.Stratification refers to the method of placing seeds in layers alternating with layers of a moisture retaining medium, such as sand, peat or vermiculite, and keeping them at a cool temperature for a certain period, but it varies considerably from species to species. The combination of high moisture and low temperature appears to trigger off biochemical changes which transform complex food substances into simpler forms utilized by the embryo when it renews growth at germination. The use of the word “stratification” has recently been extended to include all forms of cold, moist treatment whether or

Temperature-mediated changes in seed dormancy and light requirement for Penstemon palmeri (Scrophulariaceae)

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Kitchen, S.G.; Meyer, S.E. (Dept of Agriculture, Provo, UT (United States))

1992-03-01

Penstemon palmeri is a short-lived perennial herb colonizing disturbed sites in semiarid habitats in the western US. In this study seed was harvested from six native and four seeded populations during two consecutive years. In laboratory germination trials at constant 15C, considerable between-lot variation in primary dormancy and light requirement was observed. Four weeks of moist chilling (1C) induced secondary dormancy at 15C. Cold-induced secondary dormancy was reversed by one week of dark incubation at 30C. This warm incubation treatment also reduced the light requirement of unchilled, after-ripened seed. Fluctuations in dormancy and light requirement of buried seeds have been linked to seasonal changes in soil temperature. Penstemon palmeri germination responses to temperature appear to be similar to those of facultative winter annuals.

VARIABILITY IN THEIR RELATIVE DORMANCY OF Lithraea molleoides (Vell. Eng. DIASPORES

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Ana Paula de Aguiar Berger

2014-06-01

Full Text Available http://dx.doi.org/10.5902/1980509814570The large diversity of Anacardiaceae diaspores morphology has a notable repercussion in the processes of germination and emergence besides generating a differentiated behavior among the species. In this family, there are some species that present physical dormancy, some others present mechanical dormancy, others present no dormancy at all and some of them have no information detailed in the available literature. Lithraea molleoides (Vell. Eng. is one of the species which little is known regarding to dormancy. Therefore, the objective was to evaluate the germination and the emergence processes of seedlings from diaspores of this species collected in Araguari river valley, in the state of Minas Gerais, as well as to quantify the variability of dormancy intensity present among different individuals of the population. The diaspores were collected in October and November of 2004 and 2005, from six matrixes. Two experiments were set up. The germination experiment was conducted under controlled conditions and the emergence experiment was conducted in a semi-open greenhouse. Data was collected every 24 hours, up serving the protrusion of the embryo in the experiment setup in the laboratory, and the emergence of the hypocotyl of the seedling above the substrate in the experiment kept in the greenhouse. In both experiments, the diaspores originated from plant number two were more notable to some extent, having superior physiological quality compared to the others (average time between 4 and 22 days; average speeds between 0.042 and 0.0217 days-1; uncertainty between 1.62 and 3.5 bits and synchrony between 0.04 and 0.381. The high uncertainty values and the low synchrony values indicate that the germination and emergence processes of the Lithraea molleoides seedlings are spread in time, which allows us to characterize them as bearers of relative dormancy, although its intensity is variable among individuals of the

On the language and physiology of dormancy and quiescence in plants.

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Considine, Michael J; Considine, John A

2016-05-01

The language of dormancy is rich and poetic, as researchers spanning disciplines and decades have attempted to understand the spell that entranced 'Sleeping Beauty', and how she was gently awoken. The misleading use of 'dormancy', applied to annual axillary buds, for example, has confounded progress. Language is increasingly important as genetic and genomic approaches become more accessible to species of agricultural and ecological importance. Here we examine how terminology has been applied to different eco-physiological states in plants, and with pertinent reference to quiescent states described in other domains of life, in order to place plant quiescence and dormancy in a more complete context than previously described. The physiological consensus defines latency or quiescence as opportunistic avoidance states, where growth resumes in favourable conditions. In contrast, the dormant state in higher plants is entrained in the life history of the organism. Competence to resume growth requires quantitative and specific conditioning. This definition applies only to the embryo of seeds and specialized meristems in higher plants; however, mechanistic control of dormancy extends to mobile signals from peripheral tissues and organs, such as the endosperm of seed or subtending leaf of buds. The distinction between dormancy, quiescence, and stress-hardiness remains poorly delineated, most particularly in buds of winter perennials, which comprise multiple meristems of differing organogenic states. Studies in seeds have shown that dormancy is not a monogenic trait, and limited study has thus far failed to canalize dormancy as seen in seeds and buds. We argue that a common language, based on physiology, is central to enable further dissection of the quiescent and dormant states in plants. We direct the topic largely to woody species showing a single cycle of growth and reproduction per year, as these bear the majority of global timber, fruit, and nut production, as well being

Genomic Sequencing of Japanese Plum (Prunus salicina Lindl. Mutants Provides a New Model for Rosaceae Fruit Ripening Studies

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Angel Fernandez i Marti

2018-02-01

Full Text Available It has recently been described that the Japanese plum “Santa Rosa” bud sport series contains variations in ripening pattern: climacteric, suppressed-climacteric and non-climacteric types. This provides an interesting model to study the role of ethylene and other key mechanisms governing fruit ripening, softening and senescence. The aim of the current study was to investigate such differences at the genomic level, using this series of plum bud sports, with special reference to genes involved in ethylene biosynthesis, signal transduction, and sugar metabolism. Genomic DNA, isolated from leaf samples of six Japanese plum cultivars (“Santa Rosa”, “July Santa Rosa”, “Late Santa Rosa”, “Sweet Miriam”, “Roysum”, and “Casselman”, was used to construct paired-end standard Illumina libraries. Sequences were aligned to the Prunus persica genome, and genomic variations (SNPs, INDELS, and CNV's were investigated. Results determined 12 potential candidate genes with significant copy number variation (CNV, being associated with ethylene perception and signal transduction components. Additionally, the Maximum Likelihood (ML phylogenetic tree showed two sorbitol dehydrogenase genes grouping into a distinct clade, indicating that this natural group is well-defined and presents high sequence identity among its members. In contrast, the ethylene group, which includes ACO1, ACS1, ACS4, ACS5, CTR1, ERF1, ERF3, and ethylene-receptor genes, was widely distributed and clustered into 10 different groups. Thus, ACS, ERF, and sorbitol dehydrogenase proteins potentially share a common ancestor for different plant genomes, while the expansion rate may be related to ancestral expansion rather than species-specific events. Based on the distribution of the clades, we suggest that gene function diversification for the ripening pathway occurred prior to family extension. We herein report all the frameshift mutations in genes involved in sugar transport

Genomic Sequencing of Japanese Plum (Prunus salicina Lindl.) Mutants Provides a New Model for Rosaceae Fruit Ripening Studies.

Science.gov (United States)

Fernandez I Marti, Angel; Saski, Christopher A; Manganaris, George A; Gasic, Ksenija; Crisosto, Carlos H

2018-01-01

It has recently been described that the Japanese plum "Santa Rosa" bud sport series contains variations in ripening pattern: climacteric, suppressed-climacteric and non-climacteric types. This provides an interesting model to study the role of ethylene and other key mechanisms governing fruit ripening, softening and senescence. The aim of the current study was to investigate such differences at the genomic level, using this series of plum bud sports, with special reference to genes involved in ethylene biosynthesis, signal transduction, and sugar metabolism. Genomic DNA, isolated from leaf samples of six Japanese plum cultivars ("Santa Rosa", "July Santa Rosa", "Late Santa Rosa", "Sweet Miriam", "Roysum", and "Casselman"), was used to construct paired-end standard Illumina libraries. Sequences were aligned to the Prunus persica genome, and genomic variations (SNPs, INDELS, and CNV's) were investigated. Results determined 12 potential candidate genes with significant copy number variation (CNV), being associated with ethylene perception and signal transduction components. Additionally, the Maximum Likelihood (ML) phylogenetic tree showed two sorbitol dehydrogenase genes grouping into a distinct clade, indicating that this natural group is well-defined and presents high sequence identity among its members. In contrast, the ethylene group, which includes ACO1, ACS1, ACS4, ACS5, CTR1, ERF1, ERF3, and ethylene-receptor genes, was widely distributed and clustered into 10 different groups. Thus, ACS, ERF, and sorbitol dehydrogenase proteins potentially share a common ancestor for different plant genomes, while the expansion rate may be related to ancestral expansion rather than species-specific events. Based on the distribution of the clades, we suggest that gene function diversification for the ripening pathway occurred prior to family extension. We herein report all the frameshift mutations in genes involved in sugar transport and ethylene biosynthesis detected as well

Dormancy effects on the reliability of nuclear thermal propulsion systems for long-term manned space missions

International Nuclear Information System (INIS)

Shooman, M.L.; Sforza, P.M.

1993-01-01

This paper explores the effects of dormancy on the reliability of a Nuclear Thermal Propulsion (NTP) system for long-term manned space missions, such as Mars exploration. Dormancy refers to the portion of space systems operation where the power and stress levels are significantly reduced from nominal values and the authors have identified dormancy as a significant effect. Three approaches are used to evaluate the relative importance of failure rates during dormant operation: use of failure rate models involving dormancy, power cycling and fully energized operation; study of data bases which include both dormant and energized failure rates; predictions based on an Arrhenius rate process formulation. The results of these approaches suggest that for a long term manned mission the dormancy, cycle, and energized failure rates will all be important. Reliability in the energized state normally receives utmost attention and care during design, however, unless equal attention is directed to dormancy, the mission reliability may be severely compromised

Relationship between endogenous hormonal content and somatic organogenesis in callus of peach (Prunus persica L. Batsch) cultivars and Prunus persica×Prunus dulcis rootstocks.

Science.gov (United States)

Pérez-Jiménez, Margarita; Cantero-Navarro, Elena; Pérez-Alfocea, Francisco; Le-Disquet, Isabel; Guivarc'h, Anne; Cos-Terrer, José

2014-05-01

The relationship between endogenous hormones content and the induction of somatic peach plant was studied. To induce multiple shoots from callus derived from the base of stem explants of the scion cultivars 'UFO-3', 'Flariba' and 'Alice Bigi', and the peach×almond rootstocks 'Garnem' and 'GF677', propagated plants were cultured on Murashige and Skoog salts augmented with 0.1mgL(-1) of indolebutyric acid, 1mgL(-1) of 6-benzylaminopurine and 3% sucrose. The highest regeneration rate was obtained with the peach×almond rootstocks. Endogenous levels of abscisic acid (ABA), indole-3-acetic acid (IAA), zeatin (Z), zeatin riboside (ZR), ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), salicylic acid (SA), and jasmonic acid (JA) were analyzed in the organogenic callus. Lower levels of several hormones, namely Z, ZR, ABA, and ACC were found in the peach×almond rootstock compared to peach cultivars, while IAA and SA presented inconclusive returns. These results suggest that the difference in somatic organogenesis capacity observed in peach and peach×almond hybrids is markedly affected by the endogenous hormonal content of the studied genotypes. Copyright © 2014 Elsevier GmbH. All rights reserved.

Effect of different treatments on breaking dormancy of Teucrium polium

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alireza koochaki

2009-06-01

Full Text Available In order to evaluate effects of different treatments on breaking dormancy of Teucrium polium, an experiment was conducted with 3 replications in a completely randomized design. Seeds were subjected to different treatments including various levels of GA3, H2SO4, soaking with water and chilling. Germination of Teucrium polium increased with different concentrations of GA3. Percentage germination Maximum and rate was obtained at concentrations of 250, 1500 ppm (72h GA3 and combination of GA3 (1500ppm and chilling (5 ºC for a period of 14 days. GA3 (500ppm increased germination percentage but not germination rate. Soaking with water broke dormancy and induced 32% seed germination of Teucrium polium, but H2SO4, freezing (-10 ºC and combination of both treatments had no effect on dormancy.

Looking into flowering time in almond (Prunus dulcis (Mill) D. A. Webb): the candidate gene approach.

Science.gov (United States)

Silva, C; Garcia-Mas, J; Sánchez, A M; Arús, P; Oliveira, M M

2005-03-01

Blooming time is one of the most important agronomic traits in almond. Biochemical and molecular events underlying flowering regulation must be understood before methods to stimulate late flowering can be developed. Attempts to elucidate the genetic control of this process have led to the identification of a major gene (Lb) and quantitative trait loci (QTLs) linked to observed phenotypic differences, but although this gene and these QTLs have been placed on the Prunus reference genetic map, their sequences and specific functions remain unknown. The aim of our investigation was to associate these loci with known genes using a candidate gene approach. Two almond cDNAs and eight Prunus expressed sequence tags were selected as candidate genes (CGs) since their sequences were highly identical to those of flowering regulatory genes characterized in other species. The CGs were amplified from both parental lines of the mapping population using specific primers. Sequence comparison revealed DNA polymorphisms between the parental lines, mainly of the single nucleotide type. Polymorphisms were used to develop co-dominant cleaved amplified polymorphic sequence markers or length polymorphisms based on insertion/deletion events for mapping the candidate genes on the Prunus reference map. Ten candidate genes were assigned to six linkage groups in the Prunus genome. The positions of two of these were compatible with the regions where two QTLs for blooming time were detected. One additional candidate was localized close to the position of the Evergrowing gene, which determines a non-deciduous behaviour in peach.

Regulation of seed dormancy by abscisic acid and DELAY OF Germination 1

NARCIS (Netherlands)

Dekkers, S.J.W.; Bentsink, L.

2015-01-01

Physiological dormancy has been described as a physiological inhibiting mechanism that prevents radicle emergence. It can be caused by the embryo (embryo dormancy) as well as by the structures that cover the embryo. One of its functions is to time plant growth and reproduction to the most optimal

Molecular Mechanisms Underlying Abscisic Acid/Gibberellin Balance in the Control of Seed Dormancy and Germination in Cereals

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Pham A. Tuan

2018-05-01

Full Text Available Seed dormancy is an adaptive trait that does not allow the germination of an intact viable seed under favorable environmental conditions. Non-dormant seeds or seeds with low level of dormancy can germinate readily under optimal environmental conditions, and such a trait leads to preharvest sprouting, germination of seeds on the mother plant prior to harvest, which significantly reduces the yield and quality of cereal crops. High level of dormancy, on the other hand, may lead to non-uniform germination and seedling establishment. Therefore, intermediate dormancy is considered to be a desirable trait as it prevents the problems of sprouting and allows uniformity of postharvest germination of seeds. Induction, maintenance, and release of seed dormancy are complex physiological processes that are influenced by a wide range of endogenous and environmental factors. Plant hormones, mainly abscisic acid (ABA and gibberellin (GA, are the major endogenous factors that act antagonistically in the control of seed dormancy and germination; ABA positively regulates the induction and maintenance of dormancy, while GA enhances germination. Significant progress has been made in recent years in the elucidation of molecular mechanisms regulating ABA/GA balance and thereby dormancy and germination in cereal seeds, and this review summarizes the current state of knowledge on the topic.

Molecular Mechanisms Underlying Abscisic Acid/Gibberellin Balance in the Control of Seed Dormancy and Germination in Cereals

Science.gov (United States)

Tuan, Pham A.; Kumar, Rohit; Rehal, Pawanpuneet K.; Toora, Parneet K.; Ayele, Belay T.

2018-01-01

Seed dormancy is an adaptive trait that does not allow the germination of an intact viable seed under favorable environmental conditions. Non-dormant seeds or seeds with low level of dormancy can germinate readily under optimal environmental conditions, and such a trait leads to preharvest sprouting, germination of seeds on the mother plant prior to harvest, which significantly reduces the yield and quality of cereal crops. High level of dormancy, on the other hand, may lead to non-uniform germination and seedling establishment. Therefore, intermediate dormancy is considered to be a desirable trait as it prevents the problems of sprouting and allows uniformity of postharvest germination of seeds. Induction, maintenance, and release of seed dormancy are complex physiological processes that are influenced by a wide range of endogenous and environmental factors. Plant hormones, mainly abscisic acid (ABA) and gibberellin (GA), are the major endogenous factors that act antagonistically in the control of seed dormancy and germination; ABA positively regulates the induction and maintenance of dormancy, while GA enhances germination. Significant progress has been made in recent years in the elucidation of molecular mechanisms regulating ABA/GA balance and thereby dormancy and germination in cereal seeds, and this review summarizes the current state of knowledge on the topic. PMID:29875780

ABA crosstalk with ethylene and nitric oxide in seed dormancy and germination

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Erwann eArc

2013-03-01

Full Text Available Dormancy is an adaptive trait that enables seed germination to coincide with favorable environmental conditions. It has been clearly demonstrated that dormancy is induced by abscisic acid (ABA during seed development on the mother plant. After seed dispersal, germination is preceded by a decline in ABA in imbibed seeds, which results from ABA catabolism through 8’-hydroxylation. The hormonal balance between ABA and gibberellins (GAs has been shown to act as an integrator of environmental cues to maintain dormancy or activate germination. The interplay of ABA with other endogenous signals is however less documented. In numerous species, ethylene counteracts ABA signaling pathways and induces germination. In Brassicaceae seeds, ethylene prevents the inhibitory effects of ABA on endosperm cap weakening, thereby facilitating endosperm rupture and radicle emergence. Moreover, enhanced seed dormancy in Arabidopsis ethylene-insensitive mutants results from greater ABA sensitivity. Conversely, ABA limits ethylene action by down-regulating its biosynthesis. Nitric oxide (NO has been proposed as a common actor in the ABA and ethylene crosstalk in seed. Indeed, convergent evidence indicates that NO is produced rapidly after seed imbibition and promotes germination by inducing the expression of the ABA 8’-hydroxylase gene, CYP707A2, and stimulating ethylene production. The role of NO and other nitrogen-containing compounds, such as nitrate, in seed dormancy breakage and germination stimulation has been reported in several species. This review will describe our current knowledge of ABA crosstalk with ethylene and NO, both volatile compounds that have been shown to counteract ABA action in seeds and to improve dormancy release and germination.

Regulation of wheat seed dormancy by after-ripening is mediated by specific transcriptional switches that induce changes in seed hormone metabolism and signaling.

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Aihua Liu

Full Text Available Treatments that promote dormancy release are often correlated with changes in seed hormone content and/or sensitivity. To understand the molecular mechanisms underlying the role of after-ripening (seed dry storage in triggering hormone related changes and dormancy decay in wheat (Triticum aestivum, temporal expression patterns of genes related to abscisic acid (ABA, gibberellin (GA, jasmonate and indole acetic acid (IAA metabolism and signaling, and levels of the respective hormones were examined in dormant and after-ripened seeds in both dry and imbibed states. After-ripening mediated developmental switch from dormancy to germination appears to be associated with declines in seed sensitivity to ABA and IAA, which are mediated by transcriptional repressions of PROTEIN PHOSPHATASE 2C, SNF1-RELATED PROTEIN KINASE2, ABA INSENSITIVE5 and LIPID PHOSPHATE PHOSPHTASE2, and AUXIN RESPONSE FACTOR and RELATED TO UBIQUITIN1 genes. Transcriptomic analysis of wheat seed responsiveness to ABA suggests that ABA inhibits the germination of wheat seeds partly by repressing the transcription of genes related to chromatin assembly and cell wall modification, and activating that of GA catabolic genes. After-ripening induced seed dormancy decay in wheat is also associated with the modulation of seed IAA and jasmonate contents. Transcriptional control of members of the ALLENE OXIDE SYNTHASE, 3-KETOACYL COENZYME A THIOLASE, LIPOXYGENASE and 12-OXOPHYTODIENOATE REDUCTASE gene families appears to regulate seed jasmonate levels. Changes in the expression of GA biosynthesis genes, GA 20-OXIDASE and GA 3-OXIDASE, in response to after-ripening implicate this hormone in enhancing dormancy release and germination. These findings have important implications in the dissection of molecular mechanisms underlying regulation of seed dormancy in cereals.

A new ester coumarin from Ferula Persica wild, indigenous to Iran.

Science.gov (United States)

Razavi, Seyed Mehdi; Janani, Mehrnoush

2015-01-01

Ferula persica wild (Apiaceae) is a perennial herb indigenous to Iran. It has been used in folk medicine for treatment of diabetes, lowering of blood pressure and for antispasmodic, carminative, laxative and expectorant effects in central Iran. Dried ground roots of F. persica (150 g) were extracted sequentially with n-hexane, dichloromethane and methanol (MeOH), 500 ml each, using a Soxhlet apparatus. The n-hexane extract of the roots (3 g) was subjected to vacuum liquid chromatography on silica gel, eluting with solvent mixtures of increasing polarity: 100% n-hexane-ethyl acetate (EtOAc), to yield a number of fractions, Fraction 4 (80% EtOAc in n-hexane) was further analysed by preparative TLC (mobile phase was 12% acetone in chloroform) to yield a coumarin ester (10.1 mg, Rf = 0.31, blue florescent). The structure of the isolated compound was elucidated by spectroscopic means. The compound is 7-O-(4,8,12 -trihydroxy-4,8,12-trimethyl-tridecanoyl)-coumarin, named, ferulone C as a new natural product.

The Arabidopsis MYB96 transcription factor plays a role in seed dormancy.

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Lee, Hong Gil; Lee, Kyounghee; Seo, Pil Joon

2015-03-01

Seed dormancy facilitates to endure environmental disadvantages by confining embryonic growth until the seeds encounter favorable environmental conditions for germination. Abscisic acid (ABA) and gibberellic acid (GA) play a pivotal role in the determination of the seed dormancy state. ABA establishes seed dormancy, while GA triggers seed germination. Here, we demonstrate that MYB96 contributes to the fine-tuning of seed dormancy regulation through the coordination of ABA and GA metabolism. The MYB96-deficient myb96-1 seeds germinated earlier than wild-type seeds, whereas delayed germination was observed in the activation-tagging myb96-1D seeds. The differences in germination rate disappeared after stratification or after-ripening. The MYB96 transcription factor positively regulates ABA biosynthesis genes 9-CIS-EPOXYCAROTENOID DIOXYGENASE 2 (NCED2), NCED5, NCED6, and NCED9, and also affects GA biosynthetic genes GA3ox1 and GA20ox1. Notably, MYB96 directly binds to the promoters of NCED2 and NCED6, primarily modulating ABA biosynthesis, which subsequently influences GA metabolism. In agreement with this, hyperdormancy of myb96-1D seeds was recovered by an ABA biosynthesis inhibitor fluridone, while hypodormancy of myb96-1 seeds was suppressed by a GA biosynthesis inhibitor paclobutrazol (PAC). Taken together, the metabolic balance of ABA and GA underlies MYB96 control of primary seed dormancy.

Natural variation for seed longevity and seed dormancy are negatively correlated in Arabidopsis

NARCIS (Netherlands)

Nguyen, T.P.; Keizer, L.C.P.; Eeuwijk, van F.; Smeekens, S.C.M.; Bentsink, L.

2012-01-01

Dormancy is a state of metabolic arrest that facilitates the survival of organisms during environmental conditions incompatible with their regular course of life. Many organisms have deep dormant stages to promote an extended life span (increased longevity). In contrast, plants have seed dormancy

PpHB22, a member of HD-Zip proteins, activates PpDAM1 to regulate bud dormancy transition in 'Suli' pear (Pyrus pyrifolia White Pear Group).

Science.gov (United States)

Yang, Qinsong; Niu, Qingfeng; Li, Jianzhao; Zheng, Xiaoyan; Ma, Yunjing; Bai, Songling; Teng, Yuanwen

2018-06-01

Homeodomain-leucine zipper (HD-Zip) proteins, which form one of the largest and most diverse families, regulate many biological processes in plants, including differentiation, flowering, vascular development, and stress signaling. Abscisic acid (ABA) has been proved to be one of the key regulators of bud dormancy and to influence several HD-Zip genes expression. However, the role of HD-Zip genes in regulating bud dormancy remains unclear. We identified 47 pear (P. pyrifolia White Pear Group) HD-Zip genes, which were classified into four subfamilies (HD-Zip I-IV). We further revealed that gene expression levels of some HD-Zip members were closely related to ABA concentrations in flower buds during dormancy transition. Exogenous ABA treatment confirmed that PpHB22 and several other HD-Zip genes responded to ABA. Yeast one-hybrid and dual luciferase assay results combining subcellular localization showed that PpHB22 was present in nucleus and directly induced PpDAM1 (dormancy associated MADS-box 1) expression. Thus, PpHB22 is a negative regulator of plant growth associated with the ABA response pathway and functions upstream of PpDAM1. These findings enrich our understanding of the function of HD-Zip genes related to the bud dormancy transition. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Myzus persicae

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Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides provides training to identify the green peach aphid, Myzus persicae, using a compound microscope and an electronic identification key called “LUCID.” The video demonstrates key morphological structures t...

Assessment of Seed Germination and Dormancy of Thirty Seeds Lots of

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H.R Ehyaee

2012-06-01

Full Text Available Most seeds of medicinal plants due to ecological adaptation to environmental conditions have several types of dormancy. Hence, it's necessary to recognize ecological factors that affect dormancy and provide optimum conditions for germination in medicinal plant species. Thirty seed lots were used to estimate germination and dormancy of medicinal plants. Treatments were KNO3, (2% and scarification of seeds by sand paper, hypochlorite sodium and removing the seed coat with four replicates of 25 seeds. Maximum and minimum germination observed in H2O for Digitalis purpure 100% and Saponaria officinalis 0%. In KNO3 treatment, Portulaca oleracea had the highest germination of 91% and Hyocyamus niger had no any germinated seeds. In sand paper treatment, the Saponaria officinalis and Datura stramonium had maximum, 33% and minimum 0% germination respectively.

Evolution with a seed bank: The population genetic consequences of microbial dormancy.

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Shoemaker, William R; Lennon, Jay T

2018-01-01

Dormancy is a bet-hedging strategy that allows organisms to persist through conditions that are suboptimal for growth and reproduction by entering a reversible state of reduced metabolic activity. Dormancy allows a population to maintain a reservoir of genetic and phenotypic diversity (i.e., a seed bank) that can contribute to the long-term survival of a population. This strategy can be potentially adaptive and has long been of interest to ecologists and evolutionary biologists. However, comparatively little is known about how dormancy influences the fundamental evolutionary forces of genetic drift, mutation, selection, recombination, and gene flow. Here, we investigate how seed banks affect the processes underpinning evolution by reviewing existing theory, implementing novel simulations, and determining how and when dormancy can influence evolution as a population genetic process. We extend our analysis to examine how seed banks can alter macroevolutionary processes, including rates of speciation and extinction. Through the lens of population genetic theory, we can understand the extent that seed banks influence the evolutionary dynamics of microorganisms as well as other taxa.

Antioxidant capacity and fatty acid profile of Centaurea kotschyi (Boiss. and Heldr.) Hayek var. persica (Boiss.) Wagenitz from Turkey

Energy Technology Data Exchange (ETDEWEB)

Zengin, G.; Guler, G.O.; Cakmak, Y.S.; Aktumseka, A.

2011-07-01

The antioxidant capacity of the methanolic extract and the fatty acid composition of C. kotschyi var. persica were investigated. Six different chemical methods were used to determine the antioxidant capacity. The fatty acid composition was analyzed using gas chromatography. The IC50 value of the extract was determined as 37.09 ig/ml (in the DPPH assay). In the {beta}carotene/linoleic acid system, the extract exhibited 65.22% inhibition against linoleic acid oxidation. The amount of total phenolic content and total antioxidant capacity were detected as 36.52 mg gallic acid equivalent (GAE)/g and 74.93 mg ascorbic acid equivalent (AE)/g, respectively. The major fatty acid in the composition of C. kotschyi var. persica was found to be C 18:3 u3 ({beta}-linolenic acid) by GC analysis. The results presented here indicate that C. kotschyi var. persica possess strong antioxidant properties. Therefore, the species can be used as a natural additive in food, cosmetic and pharmaceutical industries. (Author).

Characterization of Pseudomonas pathovars isolated from rosaceous fruit trees in East Algeria.

Science.gov (United States)

Harzallah, D; Sadallah, S; Larous, L

2004-01-01

A survey of bacterial diseases due to Pseudomonas on rosaceous fruit trees was conducted. In forty two orchards located in the Constantine region ( East Algeria). Pseudomonas isolates were identified on the bases of their cultural and biochemical characteristics . A total of fifty nine phytopathogenic bacteria were isolated from diseased pome and stone fruit trees. Thirty one strains comparable to Pseudomonas syringae pv. syringae were isolated from cherry (Prunus avium L.), plum (P. domestica L.), apricot (P. armeniaca L.), almond (P. dulcis L.) and pear trees (Pirus communis L.); sixteen strains comparable to Pseudomonas syringae pv. morsprunorum were obtained from samples of cherry and plum. Twelve strains of Pseudomonas viridiflava were isolated from cherry, apricot and peach (Prunus persica L.).

Breeding rootstocks for Prunus species: Advances in genetic and genomics of peach and cherry as a model

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Verónica Guajardo

2015-08-01

Full Text Available Prunus rootstock is an important choice in optimizing productivity of grafted cultivars. Nevertheless, many Prunus rootstocks are notoriously intolerant to hypoxia which is caused by waterlogging and/or heavy soils. There is no available information to help select Prunus rootstocks that are tolerant to stress conditions such as root hypoxia caused by excess moisture. Information from genetic maps has demonstrated a high level of synteny among Prunus species, and this suggests that they all share a similar genomic structure. It should be possible to identify the genetic determinants involved in tolerance to hypoxia and other traits in Prunus rootstocks by applying methods to identify regions of the genome involved in the expression of important traits; these have been developed mainly in peach which is the model species for the genus. Molecular markers that are tightly linked to major genes would be useful in marker-assisted selection (MAS to optimize new rootstock selection. This article provides insight on the advances in the development of molecular markers, genetic maps, and gene identification in Prunus, mainly in peach; the aim is to provide a general approach for identifying the genetic determinants of hypoxia stress in rootstocks.

Ultrasonic actuation for MEMS dormancy-related stiction reduction

Science.gov (United States)

Kaajakari, Ville; Kan, Shyi-Herng; Lin, Li-Jen; Lal, Amit; Rodgers, M. Steven

2000-08-01

The use of ultrasonic pulses incident on surface micromachines has been shown to reduce dormancy-related failure. We applied ultrasonic pulses from the backside of a silicon substrate carrying SUMMiT processed surface micromachined rotors, used earlier as ultrasonic motors. The amplitude of the pulses was less than what is required to actuate the rotor (sub-threshold actuation). By controlling the ultrasonic pulse exposure time it was found that pulsed samples had smaller actuation voltages as compared to non-pulsed samples after twelve-hour dormancy. This result indicates that the micromachine stiction to surfaces during dormant period can be effectively eliminated, resulting in long-term stability of surface micromachines in critical applications.

Blackout cloth for dormancy induction

Science.gov (United States)

Tom Jopson

2007-01-01

The use of blackout cloth to create long night photoperiods for the induction of dormancy in certain conifer species has been an established practice for a long time. Its use was suggested by Tinus and McDonald (1979) as an effective technique, and the practice has been commonly used in Canadian forest nurseries for a number of years. Cal-Forest Nursery installed its...

BMP7 Induces Dormancy of Prostatic Tumor Stem Cell in Bone

Science.gov (United States)

2013-07-01

of NDRG1 is correlated with tumor progression and poor prog- nosis in patients with esophageal squamous cell carcinoma. Dis. Esophagus . 19:454–458...Dormancy of Prostatic Tumor Stem Cell in Bone PRINCIPAL INVESTIGATOR: Fei Xing, Ph.D...BMP7 Induces Dormancy of Prostatic Tumor Stem Cell in Bone 5b. GRANT NUMBER W81XWH-10-1-0666 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Fei

Dormancy and cold hardiness transitions in wine grape cultivars Chardonnay and Cabernet Sauvignon

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Dormancy and cold hardiness influence grapevine (Vitis vinifera L.) susceptibility to cold injury, which is a major cause of economic loss in high latitude growing regions. The objectives of this study were to compare dormancy and cold hardiness transitions in wine grape cultivars considered more (C...

Effect of ethanol and plant growth regulators on termination of potato microtuber dormancy

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Wróbel Sławomir

2015-12-01

Full Text Available The duration of dormancy varies significantly among cultivars, but even short dormancy can limit usage of potato microtubers for seed production. The aim of the research was to test efficacy of dormancy breaking by treatment with an aqueous solution of ethyl alcohol, saccharose, gibberellic acid and kinetin (ethanol treatment in comparison to treatment with aqueous solution of thiourea, daminozide and gibberellic acid (standard treatment. Prolonging the period of microtuber production at the in vitro stage significantly favored the short-ening of the dormancy and facilitated its breaking. While the standard treatment had the strongest effect, the ethanol treatment was slightly less efficient. The statistically significant differences were only observed during the first 13 days after the microtuber treatment. After that time, efficacy of ethanol and standard treatments was similar to control treatment with water. The investigated treatments had no effect on the natural decrease of ABA level in microtubers.

Methods for overcoming dormancy in Stryphnodendron pulcherrimum seeds

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Adriano Gonçalves Pereira

2016-09-01

Full Text Available Seed dormancy is a phenomenon observed in several tropical species. This condition causes low and non-uniform germination. The present study was designed to identify an efficient method of breaking seed dormancy in Stryphnodendron pulcherrimum. Seeds of four mother plants were subjected to the following treatments: immersion in sulfuric acid for 2, 4, 6, 8, 10 and 12 min and scarification on 150-grit sandpaper. Seeds were sown on substrate containing sand and sawdust (1:1. It was evaluate the days to onset seedlings emergence, seedlings emergence (SE, emergence speed index (ESI, germination (G, hard seeds (HS, dead seeds (DS, dormant seeds (DMS, abnormal seedlings (AS and dry mass of aerial part (DMAP and roots (DMR. The experimental design was completely randomized with four replications of 25 seeds for each treatment. Data were subjected to analysis of variance and means compared by Tukey’s test (p < 0.05. Significant differences among treatments were observed for ESI, SE, G, HS, DMAP and DMR. Highest HS was observed in control treatment (85%. Highest G was observed in seeds scarified with sulfuric acid for 10 min (82% and 12 min (74%. These treatments also showed highest ESI, DMAP and DMR, indicating that these scarification treatments were the most efficient in overcoming dormancy.

Hormonal Regulation of Dormancy in Developing Sorghum Seeds.

Science.gov (United States)

Steinbach, H. S.; Benech-Arnold, R. L.; Sanchez, R. A.

1997-01-01

The role of abscisic acid (ABA) and gibberellic acid (GA) in determining the dormancy level of developing sorghum (Sorghum bicolor [L.] Moench.) seeds from varieties presenting contrasting preharvest sprouting behavior (Redland B2, susceptible; IS 9530, resistant) was investigated. Panicles from both varieties were sprayed soon after pollination with fluridone or paclobutrazol to inhibit ABA and GA synthesis, respectively. Fluridone application to the panicles increased germinability of Redland B2 immature caryopses, whereas early treatment with paclobutrazol completely inhibited germination of this variety during most of the developmental period. Incubating caryopses in the presence of 100 [mu]M GA4+7 overcame the inhibitory effect of paclobutrazol, but also stimulated germination of seeds from other treatments. IS 9530 caryopses presented germination indices close to zero until physiological maturity (44 d after pollination) in control and paclobutrazol-treated particles. However, fluridone-treated caryopses were released from dormancy earlier than control and paclobutrazol-treated caryopses. Incubation in the presence of GA4+7 stimulated germination of caryopses from all treatments. Our results support the proposition that a low dormancy level (which is related to a high preharvest sprouting susceptibility) is determined not only by a low embryonic sensitivity to ABA, but also by a high GA content or sensitivity.

A simulation model for seasonal changes in dormancy and germination of weed seeds

NARCIS (Netherlands)

Vleeshouwers, L.M.; Bouwmeester, H.J.

2001-01-01

A model has been developed to simulate the annual dormancy cycle of seeds of light-requiring species in the seed bank and the germination of exhumed seeds after irradiation. Simulation of dormancy and germination is based on a physiological model concerning the action of phytochrome in the seed.

Genome-wide identification of WRKY family genes in peach and analysis of WRKY expression during bud dormancy.

Science.gov (United States)

Chen, Min; Tan, Qiuping; Sun, Mingyue; Li, Dongmei; Fu, Xiling; Chen, Xiude; Xiao, Wei; Li, Ling; Gao, Dongsheng

2016-06-01

Bud dormancy in deciduous fruit trees is an important adaptive mechanism for their survival in cold climates. The WRKY genes participate in several developmental and physiological processes, including dormancy. However, the dormancy mechanisms of WRKY genes have not been studied in detail. We conducted a genome-wide analysis and identified 58 WRKY genes in peach. These putative genes were located on all eight chromosomes. In bioinformatics analyses, we compared the sequences of WRKY genes from peach, rice, and Arabidopsis. In a cluster analysis, the gene sequences formed three groups, of which group II was further divided into five subgroups. Gene structure was highly conserved within each group, especially in groups IId and III. Gene expression analyses by qRT-PCR showed that WRKY genes showed different expression patterns in peach buds during dormancy. The mean expression levels of six WRKY genes (Prupe.6G286000, Prupe.1G393000, Prupe.1G114800, Prupe.1G071400, Prupe.2G185100, and Prupe.2G307400) increased during endodormancy and decreased during ecodormancy, indicating that these six WRKY genes may play a role in dormancy in a perennial fruit tree. This information will be useful for selecting fruit trees with desirable dormancy characteristics or for manipulating dormancy in genetic engineering programs.

Use of silicon as inductor of the resistance in potato to Myzus persicae (Sulzer) (Hemiptera: Aphididae)

International Nuclear Information System (INIS)

Gomes, Flavia B.; Moraes, Jair C.; Antunes, Cristiana; Santos, Custodio D. dos

2008-01-01

The aphid Myzus persicae (Sulzer) is an important pest of potato and causes direct harm, due to the quantity of sap extracted and for being vector of important phytovirus. This work was carried out to evaluate the action of silicon as a resistance inducer of potato to M. persicae. Four treatments were tried: foliar fertilization with silicon acid at 1%; soil fertilization with 250 ml silicic acid solution at 1%; foliar fertilization with silicon acid at 1% + soil fertilization with 250 ml silicic acid solution at 1%; and a control. The treatments were applied thirty days after the explants emergence. Fifteen days after the application of the treatments, feeding preference and some biological aspects of the aphids were evaluated. After, the content of tannins and lignin present in the leaves and the activity of the enzymes peroxidase and phenylalanine ammonia-lyase were also determined. The silicon fertilization did not affect the preference of the aphids; however it reduced fecundity and the rate of population growth of the insects. The lignin percentage increased in the leaves of plants fertilized with silicon via soil and/or foliar and the percentage of tannins increased only in the leaves fertilized via soil plus foliar. The silicon acted as a resistance inducer to M. persicae in potato. (author)

Molecular Variability Among Isolates of Prunus Necrotic Ringspot Virus from Different Prunus spp.

Science.gov (United States)

Aparicio, F; Myrta, A; Di Terlizzi, B; Pallás, V

1999-11-01

ABSTRACT Viral sequences amplified by polymerase chain reaction from 25 isolates of Prunus necrotic ringspot virus (PNRSV), varying in the symptomatology they cause in six different Prunus spp., were analyzed for restriction fragment polymorphisms. Most of the isolates could be discriminated by using a combination of three different restriction enzymes. The nucleotide sequences of the RNA 4 of 15 of these isolates were determined. Sequence comparisons and phylogenetic analyses of the RNA 4 and coat proteins (CPs) revealed that all of the isolates clustered into three different groups, represented by three previously sequenced PNRSV isolates: PV32, PE5, and PV96. The PE5-type group was characterized by a 5' untranslated region that was clearly different from that of the other two groups. The PV32-type group was characterized by an extra hexanucleotide consisting of a duplication of the six immediately preceding nucleotides. Although most of the variability was observed in the first third of the CP, the amino acid residues in this region, which were previously thought to be functionally important in the replication cycle of the virus, were strictly conserved. No clear correlation with the type of symptom or host specificity could be observed. The validity of this grouping was confirmed when other isolates recently characterized by other authors were included in these analyses.

A case of canine borreliosis in Iran caused by Borrelia persica.

Science.gov (United States)

Shirani, Darush; Rakhshanpoor, Alaleh; Cutler, Sally Jane; Ghazinezhad, Behnaz; Naddaf, Saied Reza

2016-04-01

Tick-borne relapsing fever is an endemic disease in Iran, with most cases attributed to infection by Borrelia persica, which is transmitted by Ornithodoros tholozani soft ticks. Here, we report spirochetemia in blood of a puppy residing in Tehran, Iran. The causative species was identified by use of highly discriminative IGS sequencing; the 489 bp IGS sequence obtained in our study showed 99% identity (100% coverage) when compared with B. persica sequences derived from clinical cases or from O. tholozani ticks. Our IGS sequence also showed 99% similarity over 414 bp (85% coverage) with a strain from a domestic dog, and 96% over 328 bp (69% coverage) with a strain from a domestic cat. Pet-keeping in cosmopolitan cities like Tehran has become increasingly popular in recent years. Animals are often transported into the city in cages or cardboard boxes that might also harbor minute tick larvae and/or early stages of the nymphs bringing them into the urban environment. This may pose a threat to household members who buy and keep these puppies and as a result may come into close contact with infected ticks. Copyright © 2016 Elsevier GmbH. All rights reserved.

Transcriptomic analysis of Prunus domestica undergoing hypersensitive response to plum pox virus infection.

Science.gov (United States)

Rodamilans, Bernardo; San León, David; Mühlberger, Louisa; Candresse, Thierry; Neumüller, Michael; Oliveros, Juan Carlos; García, Juan Antonio

2014-01-01

Plum pox virus (PPV) infects Prunus trees around the globe, posing serious fruit production problems and causing severe economic losses. One variety of Prunus domestica, named 'Jojo', develops a hypersensitive response to viral infection. Here we compared infected and non-infected samples using next-generation RNA sequencing to characterize the genetic complexity of the viral population in infected samples and to identify genes involved in development of the resistance response. Analysis of viral reads from the infected samples allowed reconstruction of a PPV-D consensus sequence. De novo reconstruction showed a second viral isolate of the PPV-Rec strain. RNA-seq analysis of PPV-infected 'Jojo' trees identified 2,234 and 786 unigenes that were significantly up- or downregulated, respectively (false discovery rate; FDR≤0.01). Expression of genes associated with defense was generally enhanced, while expression of those related to photosynthesis was repressed. Of the total of 3,020 differentially expressed unigenes, 154 were characterized as potential resistance genes, 10 of which were included in the NBS-LRR type. Given their possible role in plant defense, we selected 75 additional unigenes as candidates for further study. The combination of next-generation sequencing and a Prunus variety that develops a hypersensitive response to PPV infection provided an opportunity to study the factors involved in this plant defense mechanism. Transcriptomic analysis presented an overview of the changes that occur during PPV infection as a whole, and identified candidates suitable for further functional characterization.

Transcriptomic analysis of Prunus domestica undergoing hypersensitive response to plum pox virus infection.

Directory of Open Access Journals (Sweden)

Bernardo Rodamilans

Full Text Available Plum pox virus (PPV infects Prunus trees around the globe, posing serious fruit production problems and causing severe economic losses. One variety of Prunus domestica, named 'Jojo', develops a hypersensitive response to viral infection. Here we compared infected and non-infected samples using next-generation RNA sequencing to characterize the genetic complexity of the viral population in infected samples and to identify genes involved in development of the resistance response. Analysis of viral reads from the infected samples allowed reconstruction of a PPV-D consensus sequence. De novo reconstruction showed a second viral isolate of the PPV-Rec strain. RNA-seq analysis of PPV-infected 'Jojo' trees identified 2,234 and 786 unigenes that were significantly up- or downregulated, respectively (false discovery rate; FDR≤0.01. Expression of genes associated with defense was generally enhanced, while expression of those related to photosynthesis was repressed. Of the total of 3,020 differentially expressed unigenes, 154 were characterized as potential resistance genes, 10 of which were included in the NBS-LRR type. Given their possible role in plant defense, we selected 75 additional unigenes as candidates for further study. The combination of next-generation sequencing and a Prunus variety that develops a hypersensitive response to PPV infection provided an opportunity to study the factors involved in this plant defense mechanism. Transcriptomic analysis presented an overview of the changes that occur during PPV infection as a whole, and identified candidates suitable for further functional characterization.

Perspectives of biotechnologies based on dormancy phenomenon for space researches

Science.gov (United States)

Alekseev, V.; Sychev, V.; Layus, D.; Levinsky, M.; Novikova, N.; Zakhodnova, T.

Long term space missions will require a renewable source of food and an efficient method to recycle oxygen Plants especially aquatic micro algae provide an obvious solution to these problems However long duration plant growth and reproduction in space that is necessary for transportation of a control ecological life support system CELSS from Earth to other planets are problematic The introduction of heterotrophs in space CELSS is a more formidable problem as the absence of gravity creates additional difficulties for their life Dormancy phenomenon protected a great many animals and plants in harsh environmental conditions within a special resting phases of life cycle lasting from months up to hundred years This phenomenon can be quite perspective as a tool to overcome difficulties with CELSS transportation in space missions Cryptobiotic stages of microbes fungi unicellular algae and protists can survive in open space conditions that is important for interplanetary quarantine and biological security inside spacecraft Searching for life outside the Earth at such planet like Mars with extremely variable environment should be oriented on dormancy as crucial phases of a life cycle in such organisms Five major research programs aimed on study dormancy phenomenon for exobiology purposes and creation of new biotechnologies are discussed List of species candidate components of CELSS with dormancy in their life cycle used in space experiments at the Russian segment of International Space Station now includes 26 species from bacteria to fish The

Ethylene, a key factor in the regulation of seed dormancy

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Françoise eCORBINEAU

2014-10-01

Full Text Available Ethylene is an important component of the gaseous environment, and regulates numerous plant developmental processes including seed germination and seedling establishment. Dormancy, the inability to germinate in apparently favorable conditions, has been demonstrated to be regulated by the hormonal balance between abscisic acid (ABA and gibberellins (GAs. Ethylene plays a key role in dormancy release in numerous species, the effective concentrations allowing the germination of dormant seeds ranging between 0.1 and 200 μL L-1. Studies using inhibitors of ethylene biosynthesis or of ethylene action and analysis of mutant lines altered in genes involved in the ethylene signaling pathway (etr1, ein2, ain1, etr1, and erf1 demonstrate the involvement of ethylene in the regulation of germination and dormancy. Ethylene counteracts ABA effects through a regulation of ABA metabolism and signaling pathways. Moreover, ethylene insensitive mutants in Arabidopsis are more sensitive to ABA and the seeds are more dormant. Numerous data also show an interaction between ABA, GAs and ethylene metabolism and signaling pathways. It has been increasingly demonstrated that reactive oxygen species (ROS may play a significant role in the regulation of seed germination interacting with hormonal signaling pathways. In the present review the responsiveness of seeds to ethylene will be described, and the key role of ethylene in the regulation of seed dormancy via a cross-talk between hormones and other signals will be discussed.

Humidity-regulated dormancy onset in the Fabaceae: a conceptual model and its ecological implications for the Australian wattle Acacia saligna

Science.gov (United States)

Tozer, Mark G.; Ooi, Mark K. J.

2014-01-01

Background and aims Seed dormancy enhances fitness by preventing seeds from germinating when the probability of seedling survival and recruitment is low. The onset of physical dormancy is sensitive to humidity during ripening; however, the implications of this mechanism for seed bank dynamics have not been quantified. This study proposes a model that describes how humidity-regulated dormancy onset may control the accumulation of a dormant seed bank, and seed experiments are conducted to calibrate the model for an Australian Fabaceae, Acacia saligna. The model is used to investigate the impact of climate on seed dormancy and to forecast the ecological implications of human-induced climate change. Methods The relationship between relative humidity and dormancy onset was quantified under laboratory conditions by exposing freshly matured non-dormant seeds to constant humidity levels for fixed durations. The model was field-calibrated by measuring the response of seeds exposed to naturally fluctuating humidity. The model was applied to 3-hourly records of humidity spanning the period 1972–2007 in order to estimate both temporal variability in dormancy and spatial variability attributable to climatic differences among populations. Climate change models were used to project future changes in dormancy onset. Key Results A sigmoidal relationship exists between dormancy and humidity under both laboratory and field conditions. Seeds ripened under field conditions became dormant following very short exposure to low humidity (<20 %). Prolonged exposure at higher humidity did not increase dormancy significantly. It is predicted that populations growing in a temperate climate produce 33–55 % fewer dormant seeds than those in a Mediterranean climate; however, dormancy in temperate populations is predicted to increase as a result of climate change. Conclusions Humidity-regulated dormancy onset may explain observed variation in physical dormancy. The model offers a systematic

Seasonal pattern of seed dormancy in parthenium hysterophorus L

International Nuclear Information System (INIS)

Arshad Javaid, A.; Shafique, S.; Shafique, S.

2010-01-01

Earlier non-conclusive results have been reported on the initial dormancy status of parthenium (Parthenium hysterophorus L.) seeds. The present study reports the seasonal dormancy pattern of parthenium in Lahore, Pakistan where there are four distinct seasons viz. summer, autumn, winter and spring in a year. Mature parthenium seeds were collected on the last day of each month from January to December 2006 and investigations for their germination percentage and rate of germination were started on the next day. Parthenium seeds collected during coldest months of January and December showed highest germination of 100% with germination rate of 33.3% per day. Conversely, seeds collected in summer months of April to September exhibited lowest germination of 0-7% and germination rate of 0-1.75% per day. Seeds collected in rest of the months showed variable final germination percentage and germination rate ranging from 30-97% and 3.8-17.4%, respectively. Both the final germination and germination rate showed a highly significant negative correlation with the solar radiation and environmental temperature during the seed development period. The present study concludes that dormancy in parthenium seeds depends upon the temperature and solar radiation during the seed development period. (author)

Genes controlling seed dormancy and pre-harvest sprouting in a rice-wheat-barley comparison

DEFF Research Database (Denmark)

Li, Chengdao; Ni, Peixiang; Francki, Michael

2004-01-01

Pre-harvest sprouting results in significant economic loss for the grain industry around the world. Lack of adequate seed dormancy is the major reason for pre-harvest sprouting in the field under wet weather conditions. Although this trait is governed by multiple genes it is also highly heritable....... A major QTL controlling both pre-harvest sprouting and seed dormancy has been identified on the long arm of barley chromosome 5H, and it explains over 70% of the phenotypic variation. Comparative genomics approaches among barley, wheat and rice were used to identify candidate gene(s) controlling seed...... dormancy and hence one aspect of pre-harvest sprouting. The barley seed dormancy/pre-harvest sprouting QTL was located in a region that showed good synteny with the terminal end of the long arm of rice chromosome 3. The rice DNA sequences were annotated and a gene encoding GA20-oxidase was identified...

Targeting Neutrophil Protease-Mediated Degradation of Tsp-1 to Induce Metastatic Dormancy

Science.gov (United States)

2017-10-01

AWARD NUMBER: W81XWH-16-1-0615 TITLE: Targeting Neutrophil Protease-Mediated Degradation of Tsp-1 to Induce Metastatic Dormancy PRINCIPAL...29 Sep 2017 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Targeting Neutrophil Protease-Mediated Degradation of Tsp-1 to Induce Metastatic Dormancy...infection or cigarette smoke enhanced pulmonary metastasis from breast cancer in humans and mice. Similarly, autoimmune arthritis, characterized by

Pre-harvest Sprouting and Grain Dormancy in Sorghum bicolor: What Have We Learned?

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Roberto L. Benech-Arnold

2018-06-01

Full Text Available The possibility of obtaining sorghum grains with quality to match the standards for a diversity of end-uses is frequently hampered by the susceptibility to pre-harvest sprouting (PHS displayed by many elite genotypes. For these reasons, obtaining resistance to PHS is considered in sorghum breeding programs, particularly when the crop is expected to approach harvest maturity under rainy or damp conditions prevalence. As in other cereals, the primary cause for sprouting susceptibility is a low dormancy prior to crop harvest; in consequence, most research has focused in understanding the mechanisms through which the duration of dormancy is differentially controlled in genotypes with contrasting sprouting behavior. With this aim two tannin-less, red-grained inbred lines were used as a model system: IS9530 (sprouting resistant and Redland B2 (sprouting susceptible. Redland B2 grains are able to germinate well before reaching physiological maturity (PM while IS9530 ones can start to germinate at 40–45 days after pollination, well after PM. Results show that the anticipated dormancy loss displayed by Redland B2 grains is related reduced embryo sensitivity to abscisic acid (ABA and increased levels of GA upon imbibition. In turn, transcriptional data showed that ABA signal transduction is impaired in Redland B2, which appears to have an impact on GA catabolism, thus affecting the overall GA/ABA balance that regulates germination. QTL analyses were conducted to test whether previous candidate genes were located in a dormancy QTL, but also to identify new genes involved in dormancy. These analyses yielded several dormancy QTL and one of them located in chromosome 9 (qGI-9 was consistently detected even across environments. Fine mapping is already in progress to narrow down the number of candidate genes in qGI-9.

Resistance to Plum Pox Virus (PPV) in apricot (Prunus armeniaca L.) is associated with down-regulation of two MATHd genes.

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Zuriaga, Elena; Romero, Carlos; Blanca, Jose Miguel; Badenes, Maria Luisa

2018-01-27

Plum pox virus (PPV), causing Sharka disease, is one of the main limiting factors for Prunus production worldwide. In apricot (Prunus armeniaca L.) the major PPV resistance locus (PPVres), comprising ~ 196 kb, has been mapped to the upper part of linkage group 1. Within the PPVres, 68 genomic variants linked in coupling to PPV resistance were identified within 23 predicted transcripts according to peach genome annotation. Taking into account the predicted functions inferred from sequence homology, some members of a cluster of meprin and TRAF-C homology domain (MATHd)-containing genes were pointed as PPV resistance candidate genes. Here, we have characterized the global apricot transcriptome response to PPV-D infection identifying six PPVres locus genes (ParP-1 to ParP-6) differentially expressed in resistant/susceptible cultivars. Two of them (ParP-3 and ParP-4), that encode MATHd proteins, appear clearly down-regulated in resistant cultivars, as confirmed by qRT-PCR. Concurrently, variant calling was performed using whole-genome sequencing data of 24 apricot cultivars (10 PPV-resistant and 14 PPV-susceptible) and 2 wild relatives (PPV-susceptible). ParP-3 and ParP-4, named as Prunus armeniaca PPVres MATHd-containing genes (ParPMC), are the only 2 genes having allelic variants linked in coupling to PPV resistance. ParPMC1 has 1 nsSNP, while ParPMC2 has 15 variants, including a 5-bp deletion within the second exon that produces a frameshift mutation. ParPMC1 and ParPMC2 are adjacent and highly homologous (87.5% identity) suggesting they are paralogs originated from a tandem duplication. Cultivars carrying the ParPMC2 resistant (mutated) allele show lack of expression in both ParPMC2 and especially ParPMC1. Accordingly, we hypothesize that ParPMC2 is a pseudogene that mediates down-regulation of its functional paralog ParPMC1 by silencing. As a whole, results strongly support ParPMC1 and/or ParPMC2 as host susceptibility genes required for PPV infection which

Plant extracts in the control of aphids Brevicoryne brassicae (L. and Myzus persicae (SulzerExtratos vegetais no controle dos afídeos Brevicoryne brassicae (L. e Myzus persicae (Sulzer

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Rafael Reginato Ávila

2011-07-01

Full Text Available Were accomplished the effect of plant extracts of clove basil (Ocimum gratissimum L., horsetail (Equisetum hyemale L., coriander (Coriandrum sativum L. and tobacco (Nicotiana tabacum L. on Brevicoryne brassicae (L., 1758 and Myzus persicae (Sulzer, 1776 aphids in cabbage Brassica oleracea (L.. The treatments consisted of plant extracts prepared fresh and dry (concentrations of 2.5; 5.0; and 10% and the controls insecticide acephate and water. These solutions were sprayed on cabbage discs placed on agar in Petri dishes, containing twenty adult aphids. In sequence, the Petri dishes were sealed with plastic film and this procedure was repeated for the two aphid species studied. The assessment of the number of live nymphs and adults occurred at 1, 12, 24, and 72 hours after installation. The extracts of coriander and tobacco prepared in a concentration of 10% showed toxic effects similar to the organophosphate insecticide acephate, on adults and nymphs of the aphids Brevicoryne brassicae and Myzus persicae. Coriander revealed a promising alternative that deserves detailed studies regarding the performance of its active ingredients and dosage determination in order to provide a safe herbal product to control insects.Avaliou-se o efeito de extratos vegetais de alfavaca-cravo (Ocimum gratissimum L., cavalinha (Equisetum hyemale L., coentro (Coriandrum sativum L. e fumo (Nicotiana tabacum L. sobre os pulgões Brevicoryne brassicae (L., 1758 e Myzus persicae (Sulzer, 1776 em couve Brassica oleracea (L.. Os tratamentos consistiram de extratos vegetais preparados a fresco e seco (nas concentrações de 2,5; 5,0 e 10%, do padrão inseticida acefato e de água. As soluções assim obtidas foram pulverizadas em discos de couve colocados sobre agar em placas de Petri, contendo vinte pulgões adultos. Na sequência, as placas de Petri foram vedadas com filme plástico transparente, sendo este procedimento repetido para as duas espécies de afídeos. A avalia

Inheritance of fresh seed dormancy in groundnut

African Journals Online (AJOL)

SERVER

2008-02-19

Feb 19, 2008 ... Seed dormancy has been defined as the failure of an intact, viable seed to ... expected ratio of 3 dormant : 1 non-dormant seeds in F2 generations of crosses of ICGV 87378 and ICGV ... ICGV 87378 x ICGV 86158. 163. 0. 163.

Humidity-regulated dormancy onset in the Fabaceae: a conceptual model and its ecological implications for the Australian wattle Acacia saligna.

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Tozer, Mark G; Ooi, Mark K J

2014-09-01

Seed dormancy enhances fitness by preventing seeds from germinating when the probability of seedling survival and recruitment is low. The onset of physical dormancy is sensitive to humidity during ripening; however, the implications of this mechanism for seed bank dynamics have not been quantified. This study proposes a model that describes how humidity-regulated dormancy onset may control the accumulation of a dormant seed bank, and seed experiments are conducted to calibrate the model for an Australian Fabaceae, Acacia saligna. The model is used to investigate the impact of climate on seed dormancy and to forecast the ecological implications of human-induced climate change. The relationship between relative humidity and dormancy onset was quantified under laboratory conditions by exposing freshly matured non-dormant seeds to constant humidity levels for fixed durations. The model was field-calibrated by measuring the response of seeds exposed to naturally fluctuating humidity. The model was applied to 3-hourly records of humidity spanning the period 1972-2007 in order to estimate both temporal variability in dormancy and spatial variability attributable to climatic differences among populations. Climate change models were used to project future changes in dormancy onset. A sigmoidal relationship exists between dormancy and humidity under both laboratory and field conditions. Seeds ripened under field conditions became dormant following very short exposure to low humidity (humidity did not increase dormancy significantly. It is predicted that populations growing in a temperate climate produce 33-55 % fewer dormant seeds than those in a Mediterranean climate; however, dormancy in temperate populations is predicted to increase as a result of climate change. Humidity-regulated dormancy onset may explain observed variation in physical dormancy. The model offers a systematic approach to modelling this variation in population studies. Forecast changes in climate have

OVERCOMING SEED DORMANCY IN Annona macroprophyllata AND Annona purpureaUSING PLANT GROWTH REGULATORS

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GISELA FERREIRA

Full Text Available ABSTRACT Some Annonaceae seeds are known to exhibit dormancy mechanisms ranging from possible seed coat impermeability to physiological dormancy. Thus, the aim of this study was to evaluate the effects of gibberellin (GA GA3 and GA4+7 + benzyladenine (GA4+7 + BA application in seeds of Annona macroprophyllata Donn. Sm (papausa and Annona purpurea Moc. & Sessé ex Dunal (chincuya. The experiment was performed by the application of GA3 and GA4+7 + BA on seeds in concentrations of 0, 200, 400, 500, 600, 800 and 1000 mg L-1. The regulators broke the dormancy of both species. However, application of the GA4+7 + BA mixture had more significant results, with greater increases in germination in A. macroprophyllata than in A. purpurea. Treatments that promoted the highest germinations were GA4+7 + BA at a concentration of 200 mg L-1 for A. macroprophyllata (77% and 200 mg L-1 of GA4+7 + BA and 500 mg L-1 of GA3 for A. purpurea (30% and 29%, respectively. Rate index, mean time and frequency of germination were distinct for both species and both treatments. Although both GA3 and GA4+7 + BA promote germination, the GA4+7 + BA mixture was more effective than GA3 to overcoming seed dormancy of both species, A. purpurea has a harder dormancy than A. macroprophyllata

Uso de cuatro extractos organicos para el control del pulgon verde (Myzus persicae Sulz (ING

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Hernán Rodríguez Navas

2016-03-01

Full Text Available Extracts of leaves and stems of Neurolaena lobata; leaves, stems and fruits of Momordica charantia, wood of Quassia amara and seeds of Annona muricata, were tested regarding their effectiveness for control of green peach aphid (Myzus persicae. In a first stage, groups of 10 individuals of M. persicae were placed inside petri dishes together with a small and slight piece of synthetic cloth soaked with either substance extracted. Several concentrations were used. After two hours; more than 50% of the individuals had been killed in every petri dish, which allowed all extracts to pass on to the second stage. The second stage consisted of two experiments. The first one was done in spring at a greenhouse day temperature of 10°C,  using only the first three substances, each of them diluted 1:100. The second one was conducted in Summer at about 25°C with the four substances. Distilled water acted as a control in both experiments. Tobacco plants (Nicotiana tabacum infested with M. persicae were sprayed with the solutions and survivors counted 24 and 72 hours later. In the first experiment Q amara  and M. charantia had 78% and 77% effectiveness respectively, which were statiscally (P< 0.05 higher than that of N. lobata  (63%. In the second experiment, because of the warmer weather, they improved their performance, specially N. lobata (98%. This and A. muricata were found statistically (P< 0.05 higher than the others.

Arabidopsis Histone Demethylases LDL1 and LDL2 Control Primary Seed Dormancy by Regulating DELAY OF GERMINATION 1 and ABA Signaling-Related Genes

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Ming lei Zhao

2015-03-01

Full Text Available Seed dormancy controls germination and plays a critical role in regulating the beginning of the life cycle of plants. Seed dormancy is established and maintained during seed maturation and is gradually broken during dry storage (after-ripening. The plant hormone abscisic acid (ABA and DELAY OF GERMINATION1 (DOG1 protein are essential regulators of seed dormancy. Recent studies revealed that chromatin modifications are also involved in the transcription regulation of seed dormancy. Here, we showed that two Arabidopsis histone demethylases, LYSINESPECIFIC DEMETHYLASE LIKE 1 and 2 (LDL1 and LDL2 act redundantly in repressing of seed dormancy. LDL1 and LDL2 are highly expressed in the early silique developing stage. The ldl1 ldl2 double mutant displays increased seed dormancy, whereas overexpression of LDL1 or LDL2 in Arabidopsis causes reduced dormancy. Furthermore, we showed that LDL1 and LDL2 repress the expression of seed dormancy-related genes, including DOG1, ABA2 and ABI3 during seed dormancy establishment. Furthermore, genetic analysis revealed that the repression of seed dormancy by LDL1 and LDL2 requires DOG1, ABA2 and ABI3. Taken together, our findings revealed that LDL1 and LDL2 play an essential role in seed dormancy.

Combining drought survival via summer dormancy and annual biomass productivity in Dactylis glomerata L.

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Rajae eKallida

2016-02-01

Full Text Available Under Mediterranean climates, the best strategy to produce rain-fed fodder crops is to develop perennial drought resistant varieties. Summer dormancy present in native germplasm has been shown to confer a high level of survival under severe drought. Nevertheless it has also been shown to be negatively correlated with annual biomass productivity. The aim of this study was to analyse the correlations between summer dormancy and annual biomass productivity related traits and to identify quantitative trait loci (QTL for these traits in a progeny of a summer dormant cocksfoot parent (Kasbah and a summer active parent (Medly. A total of 283 offspring and the parents were phenotyped for summer dormancy, plant growth rate and heading date in Morocco and for maximum leaf elongation rate (LERm in France. The individuals were genotyped with a total of 325 markers including 59 AFLP, 64 SSR and 202 DArT markers. The offspring exhibited a large quantitative variation for all measured traits. Summer dormancy showed a negative correlation with both plant growth rate (-0.34 p<0.005 and LERm (-0.27 p<0.005. However, genotypes with both a high level of summer dormancy and a high level of plant growth rate were detected in the progeny. One genetic map per parent was built with a total length of 377 and 423 cM for Kasbah and Medly, respectively. Both different and co-localised QTL for summer dormancy and plant growth rate were identified. These results demonstrate that it should be possible to create summer dormant cocksfoot varieties with a high annual biomass productivity.

Wild Prunus Fruit Species as a Rich Source of Bioactive Compounds.

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Mikulic-Petkovsek, Maja; Stampar, Franci; Veberic, Robert; Sircelj, Helena

2016-08-01

Sugars, organic acids, carotenoids, tocopherols, chlorophylls, and phenolic compounds were quantified in fruit of 4 wild growing Prunus species (wild cherry, bird cherry, blackthorn, and mahaleb cherry) using HPLC-DAD-MSn. In wild Prunus, the major sugars were glucose and fructose, whereas malic and citric acids dominated among organic acids. The most abundant classes of phenolic compounds in the analyzed fruit species were anthocyanins, flavonols, derivatives of cinnamic acids, and flavanols. Two major groups of anthocyanins measured in Prunus fruits were cyanidin-3-rutinoside and cyanidin-3-glucoside. Flavonols were represented by 19 derivatives of quercetin, 10 derivatives of kaempferol, and 2 derivatives of isorhamnetin. The highest total flavonol content was measured in mahaleb cherry and bird cherry, followed by blackthorn and wild cherry fruit. Total phenolic content varied from 2373 (wild cherry) to 11053 mg GAE per kg (bird cherry) and ferric reducing antioxidant power antioxidant activity from 7.26 to 31.54 mM trolox equivalents per kg fruits. © 2016 Institute of Food Technologists®

Dormancy release and flowering time in Ziziphus jujuba Mill., a "direct flowering" fruit tree, has a facultative requirement for chilling.

Science.gov (United States)

Meir, Michal; Ransbotyn, Vanessa; Raveh, Eran; Barak, Simon; Tel-Zur, Noemi; Zaccai, Michele

2016-03-15

In deciduous fruit trees, the effect of chilling on flowering has mostly been investigated in the "indirect flowering" group, characterized by a period of rest between flower bud formation and blooming. In the present study, we explored the effects of chilling and chilling deprivation on the flowering of Ziziphus jujuba, a temperate deciduous fruit tree belonging to the "direct flowering" group, in which flower bud differentiation, blooming and fruit development occur after dormancy release, during a single growing season. Dormancy release, vegetative growth and flowering time in Z. jujuba cv. Ben-Li were assessed following several treatments of chilling. Chilling treatments quantitatively decreased the timing of vegetative bud dormancy release, thereby accelerating flowering, but had no effect on the time from dormancy release to flowering. Trees grown at a constant temperature of 25°C, without chilling, broke dormancy and flowered, indicating the facultative character of chilling in this species. We measured the expression of Z. jujuba LFY and AP1 homologues (ZjLFY and ZjAP1). Chilling decreased ZjLFY expression in dormant vegetative buds but had no effect on ZjAP1expression, which reached peak expression before dormancy release and at anthesis. In conclusion, chilling is not obligatory for dormancy release of Z. jujuba cv. Ben-Li vegetative buds. However, the exposure to chilling during dormancy does accelerate vegetative bud dormancy release and flowering. Copyright © 2016 Elsevier GmbH. All rights reserved.

Bud dormancy in apple trees after thermal fluctuations

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Rafael Anzanello

2014-06-01

Full Text Available The objective of this work was to evaluate the effect of heat waves on the evolution of bud dormancy, in apple trees with contrasting chilling requirements. Twigs of 'Castel Gala' and 'Royal Gala' were collected in orchards in Papanduva, state of Santa Catarina, Brazil, and were exposed to constant (3°C or alternating (3 and 15°C for 12/12 hours temperature, combined with zero, one or two days a week at 25°C. Two additional treatments were evaluated: constant temperature (3°C, with a heat wave of seven days at 25°C, in the beginning or in the middle of the experimental period. Periodically, part of the twigs was transferred to 25°C for daily budburst evaluation of apical and lateral buds. Endodormancy (dormancy induced by cold was overcome with less than 330 chilling hours (CH of constant cold in 'Castel Gala' and less than 618 CH in 'Royal Gala'. A daily 15°C-temperature cycle did not affect the endodormancy process. Heat waves during endodormancy resulted in an increased CH to achieve bud requirements. The negative effect of high temperature depended on the lasting of this condition. Chilling was partly cancelled during dormancy when the heat wave lasted 36 continuous hours or more. Therefore, budburst prediction models need adjustments, mainly for regions with mild and irregular winters, such as those of Southern Brazil.

In vitro Ruminal Gas Production Kinetics of Four Fodder Trees Ensiled With or Without Molasses and Urea

Institute of Scientific and Technical Information of China (English)

Abdelfattah Z M Salem; ZHOU Chuan-she; TAN Zhi-liang; Miguel Mellado; Moises Cipriano Salazar; Mona M M Y Elghandopur; Nicholas E Odongo

2013-01-01

This study investigated if the addition of urea (U), molasses (M) or their 1:1 (v/v) mixture during ensiling increases the nutritional value of forage from four fodder trees (Prunus persica, Leucaena esculenta, Acacia farnesiana, and Prunus domestica). Forage samples of fodder trees were collected in triplicate (three individual samples of each species) and subjected to an in vitro gas production (GP) procedure. Fermentation at 24 h (GP24), short-chain volatile fatty acids (SCFA), and microbial crude protein production (MCP), in vitro organic matter digestibility (OMD), metabolizable energy (ME) and dry matter degradability (DMD) were estimated. Forage samples were incubated for 72 h in an incubator at 39oC and the volume of GP was recorded at 2, 4, 6, 8, 10, 12, 24, 48, and 72 h of incubation using the reading pressure technique. The rumen fermentation profiles were highest for P. persica, which showed the highest (P<0.0001) DMD, ME, OMD, SCFA, GP24 and MCP. On the other hand L. esculenta had the lowest (P<0.0001) DMD, SCFA, MCP;P. domestica had the lowest (P<0.0001) OMD. The addition of M to silage increased (P<0.0001) ME and OMD, as well as GP. However, the addition of U and the mixture of U and M reduced (P<0.0001) DMD, ME, OMD, SCFA, GY24 and MCP. These results show that P. persica has the highest nutritive value and L. esculenta the lowest for ruminants. Additionally, the addition of M to forage from fodder trees increases rumen GP and fermentation, which may improve nutrient utilization in ruminants.

Crosstalk of PmCBFs and PmDAMs Based on the Changes of Phytohormones under Seasonal Cold Stress in the Stem of Prunus mume

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Kai Zhao

2018-01-01

Full Text Available Plants facing the seasonal variations always need a growth restraining mechanism when temperatures turn down. C-repeat binding factor (CBF genes work essentially in the cold perception. Despite lots of researches on CBFs, the multiple crosstalk is still interesting on their interaction with hormones and dormancy-associated MADS (DAM genes in the growth and dormancy control. Therefore, this study highlights roles of PmCBFs in cold-induced dormancy from different orgens. And a sense-response relationship between PmCBFs and PmDAMs is exhibited in this process, jointly regulated by six PmCBFs and PmDAM4–6. Meantime, GA3 and ABA showed negative and positive correlation with PmCBFs expression levels, respectively. We also find a high correlation between IAA and PmDAM1–3. Finally, we display the interaction mode of PmCBFs and PmDAMs, especially PmCBF1-PmDAM1. These results can disclose another view of molecular mechanism in plant growth between cold-response pathway and dormancy regulation together with genes and hormones.

Basic RNases of wild almond (Prunus webbii): cloning and characterization of six new S-RNase and one "non-S RNase" genes.

Science.gov (United States)

Banović, Bojana; Surbanovski, Nada; Konstantinović, Miroslav; Maksimović, Vesna

2009-03-01

In order to investigate the S-RNase allele structure of a Prunus webbii population from the Montenegrin region of the Balkans, we analyzed 10 Prunus webbii accessions. We detected 10 different S-RNase allelic variants and obtained the nucleotide sequences for six S-RNases. The BLAST analysis showed that these six sequences were new Prunus webbii S-RNase alleles. It also revealed that one of sequenced alleles, S(9)-RNase, coded for an amino acid sequence identical to that for Prunus dulcis S(14)-RNase, except for a single conservative amino acid replacement in the signal peptide region. Another, S(3)-RNase, was shown to differ by only three amino acid residues from Prunus salicina Se-RNase. The allele S(7)-RNase was found to be inactive by stylar protein isoelectric focusing followed by RNase-specific staining, but the reason for the inactivity was not at the coding sequence level. Further, in five of the 10 analyzed accessions, we detected the presence of one active basic RNase (marked PW(1)) that did not amplify with S-RNase-specific DNA primers. However, it was amplified with primers designed from the PA1 RNase nucleotide sequence (basic "non-S RNase" of Prunus avium) and the obtained sequence showed high homology (80%) with the PA1 allele. Although homologs of PA1 "non-S RNases" have been reported in four other Prunus species, this is the first recorded homolog in Prunus webbii. The evolutionary implications of the data are discussed.

Biological activity of various extracts and phenolic content of Micromeria persica and M. hedgei

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A. Sonboli

2015-07-01

Full Text Available Background and objectives: Lamiaceae members have long been used in Iranian Traditional Medicine (ITM for their various medicinal properties. The main objective of this study was to evaluate the antioxidant capacity and antimicrobial activity as well as the total phenolic content (TPC of the various extracts and fractions of two Iranian endemic Micromeria (M. persica and M. hedgei. Methods: Plant materials were extracted with methanol by maceration for 24 h. Then, the methanol extract (ME was further fractionated to obtain the chloroform (M-C and water (M-W fractions. The antimicrobial activity was investigated against seven Gram-positive and -negative bacteria and three fungi. Antioxidant activity was evaluated by DPPH method and the data were compared with their total phenolic contents. Results: The nonpolar sub fractions (M-C of both plants were active against pathogens especially Staphylococcus epidermidis and Bacillus subtilis with equal MIC values of3.75 and 7.5 mg/mL, respectively. Antioxidant activity evaluation showed that the polar fractions of both Micromeria species were stronger than nonpolar fractions, while the more considerable effect was observed for the water soluble fraction of the extract for M. hedgei with IC50 value of 59.1 µg/mL in comparison to M. persica (IC50 = 76.3 µg/mL. The highest gallic acid equivalent (GAE total phenolic contents was found to be 263.5 ± 1.5 and 256.3 ± 3.1 mg/g dry weight for M-W extracts of M. hedgei and M. persica, respectively. Conclusion: The results indicated that the two species might be suggested as new potential sources of natural antioxidant and antimicrobial agents.

Rack-1, GAPDH3, and actin: proteins of Myzus persicae potentially involved in the transcytosis of beet western yellows virus particles in the aphid

International Nuclear Information System (INIS)

Seddas, Pascale; Boissinot, Sylvaine; Strub, Jean-Marc; Dorsselaer, Alain van; Regenmortel, Marc H.V. van; Pattus, Franc

2004-01-01

Beet western yellows virus (BWYV) is a Polerovirus that relies on the aphid Myzus persicae for its transmission, in a persistent-circulative mode. To be transmitted, the virus must cross the midgut and the accessory salivary glands (ASG) epithelial barriers in a transcytosis mechanism where vector receptors interact with virions. In this paper, we report in vitro interaction experiments between BWYV and aphid components. Using the M. persicae clone from Colmar, we showed that a set of aphid polypeptides, separated by SDS-PAGE or 2D electrophoresis (2DE), can bind in vitro to purified wild type or mutant particles. Using subcellular fractionation, we showed that the 65-kDa polypeptide identified as symbionin is a soluble protein whereas the other polypeptides seem to be associated more or less strongly to the membrane. We hypothesize that three polypeptides, identified by mass spectrometry as Rack-1, GAPDH3, and actin, may be involved in the epithelial transcytosis of virus particles in the aphid vector

Dormancy and germination in short-lived lepidium perfoliatu l. (brassicaceae) seeds

International Nuclear Information System (INIS)

Tang, An-Jun; Tian, M.; Long, Chun-Lin

2010-01-01

To understand germination timing in an ecological context, the response to environmental events that effect seed dormancy is central and has to be combined with knowledge of germination responses to different ecological factors. In this study, seed dormancy, germination and seedling survival of annual short-lived clasping pepper weed Lepidium perfoliatum L. (Brassicaceae) were investigated. Three types of pre-treatments viz., various temperature dry storage, light and water stress were tested as possible dormancy and survival-affecting environmental events. Fresh mature seeds were greatly dormant. Warm (30 deg. C) dry storage more facilitated breaking dormancy, they germinated well under apt conditions (e.g. 20 deg. C and 10/20 deg. C plus periodic light, 14 h/d). For those seeds which underwent after-ripening, they could germinate at a range of constant temperatures (4, 10, 15, 20, 25, and 30 deg. C) and one alternating temperature (10/20 deg. C). Under alternating temperature regimes, the final percent germination of L. perfoliatum seeds increased from 37 deg. C to 93% when temperature altered from 4/10 deg. C to 10/20 deg. C in light, then decreased with increasing temperature. The germination pattern under constant temperature conditions was similar to that under alternating temperature and significant differences in final percent germinations and rates of germination were observed among different temperatures. Under different light treatments, final germination of showed significant differences, only with 35% of germination percentage in dark, much lower than those in red and white light (i.e. 93% and 91%, respectively). GA3 could promote the germination of non-dormant seeds in dark. When water potentials were reduced, final percent germination decreased dramatically, and few seeds germinated at -0.98 MPa (generated by PEG-8000). The changes of proline content in resultant seedlings were reverse to that of final percent germination with changing water

Comparison of Electric Toothbrush, Persica and Chlorhexidine Mouthwashes on Reduction of Gingival Enlargement in Orthodontic Patients: A Randomised Clinical Trial.

Science.gov (United States)

Farhadian, Nasrin; Bidgoli, Mohsen; Jafari, Farhad; Mahmoudzadeh, Majid; Yaghobi, Mahdi; Miresmaeili, Amirfarhang

2015-01-01

To compare the efficacy of chlorhexidine, Persica mouthwash and electric toothbrushes in improving gingival enlargement in patients with fixed orthodontic appliances. Seventy-two orthodontic patients with at least two sites of gingival enlargement were randomly allocated into four equal groups: 1) manual toothbrush; 2) electric toothbrush; 3) manual toothbrush+Persica mouthwash; 4) manual toothbrush+chlorhexidine mouthwash. All participants were instructed to brush their teeth at least twice a day. The subjects in groups 3 and 4 were instructed to use Persica or chlorhexidine according to the respective manufacturer's instructions. Bleeding on probing (BOP) index, gingival index (GI), O'Leary's plaque index (PI) and constructed hyperplastic index (HI) of all the subjects were measured in a blind manner at the start of the study and 2 weeks later. Changes of indices in the entire oral cavity and individual affected teeth were analysed with SPSS 16 using chi-square, ANOVA, ANCOVA, LSD and the paired t-test. In the entire oral cavity, there was a statistically significant improvement in indices in all the groups except for HI, which significantly improved only in group 4 (p=0.001). Data of individual teeth with hyperplastic gingiva showed significant reduction of all the variables except for HI in group 1 (p=0.08). No significant differences were found between groups 1 and 2 or between groups 3 and 4. The efficacy of Persica was similar to that of chlorhexidine in improving gingival conditions. None of the treatment modalities could reduce gingival enlargement to the clinically acceptable level of health.

The effects of temperature on the dormancy and germination of Cirsium arvense (L. Scop. seeds

Directory of Open Access Journals (Sweden)

Anna Bochenek

2011-01-01

Full Text Available The ecophysiological regulation of seed dormancy in perennial species and those with a varied life cycle has not been studied in detail yet. That is why an attempt has been made to determine the Cirsium arvense seed water relations during stratification and afterripening at different temperatures and germination at constant or fluctuating temperatures on the basis of the hydrotime model. The obtained results showed that breaking of the primary dormancy of achenes took place only during the first stratification month at moderate temperatures, mainly due to an increase in the average water-stress tolerance in a seed population. The induction of secondary seed dormancy during after-ripening at all temperatures resulted mostly from a substantial loss of the seeds' ability to tolerate water stress. Fluctuating temperatures affected neither seed germination nor the hydrotime model parameters. The analysis of the variations of hydrotime model parameters allows a better understanding of the physiological basis of seed dormancy relief and induction.

Optimization of microwave roasting of almond (Prunus dulcis)

Science.gov (United States)

Microwave (MW) almond roasting was investigated as an alternative to hot air (HA) roasting. Nonpareil almonds (Prunus dulcis) were roasted at 140°C in a convection oven for different times to achieve light, medium, and dark roasting levels. Several instrumental measurements were taken, establishin...

Seed dormancy and germination in Jeffersonia dubia (Berberidaceae) as affected by temperature and gibberellic acid.

Science.gov (United States)

Rhie, Y H; Lee, S Y; Kim, K S

2015-03-01

The genus Jeffersonia, which contains only two species, has a trans-Atlantic disjunct distribution. The aims of this study were to determine the requirements for breaking dormancy and germination of J. dubia seeds and to compare its dormancy characteristics with those of the congener in eastern North America. Ripe seeds of J. dubia contain an underdeveloped embryo and were permeable to water. In nature, seeds were dispersed in May, while embryos began to grow in September, and were fully elongated by late November. Germination started in March of the next year, and seeds emerged as seedlings soon after germination. In laboratory experiments, incubation at high temperatures (25 °C, 25/15 °C) for at least 8 weeks was required to initiate embryo growth, while a transfer to moderate temperatures (20/10 °C, 15/6 °C) was needed for the completion of embryo growth. At least 8 weeks at 5 °C was effective in overcoming physiological dormancy and for germination in seeds after the embryos had fully elongated. Thus, both high and low temperatures were essential to break dormancy. Gibberellic acid (GA3 ) treatment could substitute for the high temperature requirement, but not for the low temperature requirement. Based on the dormancy-breaking requirements, it is confirmed that the seeds have deep simple morphophysiological dormancy. This dormancy type is similar to that of seeds of the eastern North American species J. diphylla. Although seeds require 10-11 months from seed dispersal to germination in nature, under controlled conditions they required only 3 months after treatment with 1000 mg·l(-1) GA3 , followed by incubation at 15/6 °C. This represents practical knowledge for propagation of these plants from seed. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

What prolongs a butterfly's life?: Trade-offs between dormancy, fecundity and body size.

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Elena Haeler

Full Text Available In butterflies, life span often increases only at the expense of fecundity. Prolonged life span, on the other hand, provides more opportunities for oviposition. Here, we studied the association between life span and summer dormancy in two closely related species of Palearctic Meadow Brown butterflies, the endemic Maniola nurag and the widespread M. jurtina, from two climatic provenances, a Mediterranean and a Central European site, and tested the relationships between longevity, body size and fecundity. We experimentally induced summer dormancy and hence prolonged the butterflies' life in order to study the effects of such a prolonged life. We were able to modulate longevity only in Mediterranean females by rearing them under summer photoperiodic conditions (light 16 h : dark 8 h, thereby more than doubling their natural life span, to up to 246 days. Central European individuals kept their natural average live span under all treatments, as did Mediterranean individuals under autumn treatment (light 11: dark 13. Body size only had a significant effect in the smaller species, M. nurag, where it affected the duration of dormancy and lifetime fecundity. In the larger species, M. jurtina, a prolonged adult life span did, surprisingly, not convey any fecundity loss. In M. nurag, which generally deposited fewer eggs, extended life had a fecundity cost. We conclude that Mediterranen M. jurtina butterflies have an extraordinary plasticity in aging which allows them to extend life span in response to adverse environmental conditions and relieve the time limitation on egg-laying while maintaining egg production at equal levels.

Murine hematopoietic stem cell dormancy controlled by induction of a novel short form of PSF1 by histone deacetylase inhibitors

International Nuclear Information System (INIS)

Han, Yinglu; Gong, Zhi-Yuan; Takakura, Nobuyuki

2015-01-01

Hematopoietic stem cells (HSCs) can survive long-term in a state of dormancy. Little is known about how histone deacetylase inhibitors (HDACi) affect HSC kinetics. Here, we use trichostatin A (TSA), a histone deacetylase inhibitor, to enforce histone acetylation and show that this suppresses cell cycle entry by dormant HSCs. Previously, we found that haploinsufficiency of PSF1, a DNA replication factor, led to attenuation of the bone marrow (BM) HSC pool size and lack of acute proliferation after 5-FU ablation. Because PSF1 protein is present in CD34 + transiently amplifying HSCs but not in CD34 − long-term reconstituting-HSCs which are resting in a dormant state, we analyzed the relationship between dormancy and PSF1 expression, and how a histone deacetylase inhibitor affects this. We found that CD34 + HSCs produce long functional PSF1 (PSF1a) but CD34 − HSCs produce a shorter possibly non-functional PSF1 (PSF1b, c, dominantly PSF1c). Using PSF1a-overexpressing NIH-3T3 cells in which the endogenous PSF1 promoter is suppressed, we found that TSA treatment promotes production of the shorter form of PSF1 possibly by inducing recruitment of E2F family factors upstream of the PSF1 transcription start site. Our data document one mechanism by which histone deacetylase inhibitors affect the dormancy of HSCs by regulating the DNA replication factor PSF1. - Highlights: • Hematopoetic stem cell dormancy is controlled by histone deacetylation inhibitors. • Dormancy of HSCs is associated with a shorter form of non-functional PSF1. • Histone deacetylase inhibitors suppress PSF1 promoter activity

Murine hematopoietic stem cell dormancy controlled by induction of a novel short form of PSF1 by histone deacetylase inhibitors

Energy Technology Data Exchange (ETDEWEB)

Han, Yinglu; Gong, Zhi-Yuan [Department of Signal Transduction, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Takakura, Nobuyuki, E-mail: ntakaku@biken.osaka-u.ac.jp [Department of Signal Transduction, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Japan Science Technology Agency, CREST, K' s Gobancho, 7, Gobancho, Chiyoda-ku, Tokyo 102-0076 (Japan)

2015-06-10

Hematopoietic stem cells (HSCs) can survive long-term in a state of dormancy. Little is known about how histone deacetylase inhibitors (HDACi) affect HSC kinetics. Here, we use trichostatin A (TSA), a histone deacetylase inhibitor, to enforce histone acetylation and show that this suppresses cell cycle entry by dormant HSCs. Previously, we found that haploinsufficiency of PSF1, a DNA replication factor, led to attenuation of the bone marrow (BM) HSC pool size and lack of acute proliferation after 5-FU ablation. Because PSF1 protein is present in CD34{sup +} transiently amplifying HSCs but not in CD34{sup −} long-term reconstituting-HSCs which are resting in a dormant state, we analyzed the relationship between dormancy and PSF1 expression, and how a histone deacetylase inhibitor affects this. We found that CD34{sup +} HSCs produce long functional PSF1 (PSF1a) but CD34{sup −} HSCs produce a shorter possibly non-functional PSF1 (PSF1b, c, dominantly PSF1c). Using PSF1a-overexpressing NIH-3T3 cells in which the endogenous PSF1 promoter is suppressed, we found that TSA treatment promotes production of the shorter form of PSF1 possibly by inducing recruitment of E2F family factors upstream of the PSF1 transcription start site. Our data document one mechanism by which histone deacetylase inhibitors affect the dormancy of HSCs by regulating the DNA replication factor PSF1. - Highlights: • Hematopoetic stem cell dormancy is controlled by histone deacetylation inhibitors. • Dormancy of HSCs is associated with a shorter form of non-functional PSF1. • Histone deacetylase inhibitors suppress PSF1 promoter activity.

Incorporating microbial dormancy dynamics into soil decomposition models to improve quantification of soil carbon dynamics of northern temperate forests

Science.gov (United States)

He, Yujie; Yang, Jinyan; Zhuang, Qianlai; Harden, Jennifer W.; McGuire, A. David; Liu, Yaling; Wang, Gangsheng; Gu, Lianhong

2015-01-01

Soil carbon dynamics of terrestrial ecosystems play a significant role in the global carbon cycle. Microbial-based decomposition models have seen much growth recently for quantifying this role, yet dormancy as a common strategy used by microorganisms has not usually been represented and tested in these models against field observations. Here we developed an explicit microbial-enzyme decomposition model and examined model performance with and without representation of microbial dormancy at six temperate forest sites of different forest types. We then extrapolated the model to global temperate forest ecosystems to investigate biogeochemical controls on soil heterotrophic respiration and microbial dormancy dynamics at different temporal-spatial scales. The dormancy model consistently produced better match with field-observed heterotrophic soil CO2 efflux (RH) than the no dormancy model. Our regional modeling results further indicated that models with dormancy were able to produce more realistic magnitude of microbial biomass (analysis showed that soil organic carbon content was the dominating factor (correlation coefficient = 0.4–0.6) in the simulated spatial pattern of soil RHwith both models. In contrast to strong temporal and local controls of soil temperature and moisture on microbial dormancy, our modeling results showed that soil carbon-to-nitrogen ratio (C:N) was a major regulating factor at regional scales (correlation coefficient = −0.43 to −0.58), indicating scale-dependent biogeochemical controls on microbial dynamics. Our findings suggest that incorporating microbial dormancy could improve the realism of microbial-based decomposition models and enhance the integration of soil experiments and mechanistically based modeling.

Vernalization and the Chilling Requirement to Exit Bud Dormancy: Shared or Separate Regulation?

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Amy M Brunner

2014-12-01

Full Text Available Similarities have long been recognized between vernalization, the prolonged exposure to cold temperatures that promotes the floral transition in many plants, and the chilling requirement to release bud dormancy in woody plants of temperate climates. In both cases the extended chilling period occurring during winter is used to coordinate developmental events to the appropriate seasonal time. However, whether or not these processes share common regulatory components and molecular mechanisms remain largely unknown. Both gene function and association genetics studies in Populus are beginning to answer this question. In Populus, studies have revealed that orthologs of the antagonistic flowering time genes FT and CEN/TFL1 might have central roles in both processes. We review Populus seasonal shoot development related to dormancy release and the floral transition and evidence for FT/TFL1-mediated regulation of these processes to consider the question of regulatory overlap. In addition, we discuss the potential for and challenges to integrating functional and population genomics studies to uncover the regulatory mechanisms underpinning these processes in woody plant systems.

The site of potato leafroll virus multiplication in its vector, Myzus persicae : an anatomical study

NARCIS (Netherlands)

Ponsen, M.B.

1972-01-01

In search of the site of PLRV multiplication in its vector a detailed study was made of the anatomy of the aphid, Myzus persicae SULZ. The findings are summarized in the following lines:

Alimentary canal

The most anterior part of

Comportamento de duas cultivares de pessegueiro com interenxerto da ameixeira 'Januária' Behavior of two peach cultivars with 'Januária' as a Japanese plum interstock

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JOÃO ALEXIO SCARPARE FILHO

2000-04-01

Full Text Available Os efeitos da utilização de interenxerto (filtro da ameixeira 'Januária' (Prunus salicina L. foram verificados em duas cultivares de pessegueiro (Prunus persica L., Tropical e Ouromel-2. O porta-enxerto básico utilizado foi o pessegueiro 'Okinawa'. Foram avaliadas duas safras, respectivamente, na 4ª e 5ª folha de plantas enxertadas e estabelecidas no campo em 1994. O uso do enxerto intermediário diminuiu o vigor das plantas -- perímetro e área da secção do tronco, perímetro das pernadas e comprimento dos entrenós -- e aumentou o peso do fruto e a produção por planta, em comparação com as copas-controle enxertadas diretamente no 'Okinawa'. A eficiência produtiva, o índice de fertilidade, o florescimento e a frutificação efetiva foram incrementados com o uso do filtro. A interenxertia com ameixeira 'Januária' apresenta adequadas características de compatibilidade com o pessegueiro, como forma de compactar as copas e aumentar a produtividade e o tamanho do fruto.The effects of interstock with 'Januária' Japanese plum (Prunus salicina L. were verified in the performance of peach (Prunus persica L. cultivars Tropical and Ouromel-2. The basic rootstock used was 'Okinawa' peach. Two crops were evaluated at fourth and fifth leaves of plants established in 1994. The interstock caused decrease of the vigour of the plants -- perimeter and cross-sectional area of the trunk, perimeter of the primary branches and length of the internodes -- and increased fruit weight and production per plant, in comparison to the plant control without interstock budded on 'Okinawa'. Yield efficiency, fertility index, flowering and fruit set were increased with 'Januária' interstock. This interstock process presents an adequate characteristic of compatibility for the peach tree, as a form of compacting the plants, increasing the productivity and the fruit size.

Synteny conservation between two distantly-related Rosaceae genomes: Prunus (the stone fruits and Fragaria (the strawberry

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Sargent Daniel J

2008-06-01

Full Text Available Abstract Background The Rosaceae encompass a large number of economically-important diploid and polyploid fruit and ornamental species in many different genera. The basic chromosome numbers of these genera are x = 7, 8 and 9 and all have compact and relatively similar genome sizes. Comparative mapping between distantly-related genera has been performed to a limited extent in the Rosaceae including a comparison between Malus (subfamily Maloideae and Prunus (subfamily Prunoideae; however no data has been published to date comparing Malus or Prunus to a member of the subfamily Rosoideae. In this paper we compare the genome of Fragaria, a member of the Rosoideae, to Prunus, a member of the Prunoideae. Results The diploid genomes of Prunus (2n = 2x = 16 and Fragaria (2n = 2x = 14 were compared through the mapping of 71 anchor markers – 40 restriction fragment length polymorphisms (RFLPs, 29 indels or single nucleotide polymorphisms (SNPs derived from expressed sequence tags (ESTs and two simple-sequence repeats (SSRs – on the reference maps of both genera. These markers provided good coverage of the Prunus (78% and Fragaria (78% genomes, with maximum gaps and average densities of 22 cM and 7.3 cM/marker in Prunus and 32 cM and 8.0 cM/marker in Fragaria. Conclusion Our results indicate a clear pattern of synteny, with most markers of each chromosome of one of these species mapping to one or two chromosomes of the other. A large number of rearrangements (36, most of which produced by inversions (27 and the rest (9 by translocations or fission/fusion events could also be inferred. We have provided the first framework for the comparison of the position of genes or DNA sequences of these two economically valuable and yet distantly-related genera of the Rosaceae.

Peach Water Relations, Gas Exchange, Growth and Shoot Mortality under Water Deficit in Semi-Arid Weather Conditions

OpenAIRE

Rahmati, Mitra; Davarynejad, Gholam Hossein; G?nard, Michel; Bannayan, Mohammad; Azizi, Majid; Vercambre, Gilles

2015-01-01

In this study the sensitivity of peach tree (Prunus persica L.) to three water stress levels from mid-pit hardening until harvest was assessed. Seasonal patterns of shoot and fruit growth, gas exchange (leaf photosynthesis, stomatal conductance and transpiration) as well as carbon (C) storage/mobilization were evaluated in relation to plant water status. A simple C balance model was also developed to investigate sink-source relationship in relation to plant water status at the tree level. The...

Yield and fruit quality of peach scion by using rootstocks propagated by air layering and seed

OpenAIRE

Picolotto,Luciano; Fachinello,José Carlos; Bianchi,Valmor João; Manica-Berto,Roberta; Pasa,Mateus da Silveira; Schmitz,Juliano Dutra

2010-01-01

In rootstock propagation, several methods can be used; however few practices are adopted due to the lack of information about the behavior of stionic combinations at field. The work aimed to compare the propagation method by air layering with the traditional propagation system by seeds using the scion peach [Prunus persica (L.) Batsch] cultivar Granada. The following variables were measured: yield, fruit weight and size, skin color, flesh firmness, total soluble solids content (TSS) and titat...

The Effect of Methanolic Extract of Otostegia persica on Serum Glucose Level and Renal Function Indicators in Streptozotocin Induced Diabetic Rats

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Mahdiye Hedayati

2012-05-01

Full Text Available Background: Regarding the antioxidant property of Otostegia persica extract and the role of antioxidants in Diabetes mellitus treatment, in this study the effect of extract on serum glucose level and renal function indicators was determined in diabetic male rats. Materials and Methods: Diabetes mellitus (type I was inducted in male rats using intraperitoneal injection of streptozotocin (STZ (65 mg/kg. To determine blood glucose, urea, and creatinine serum levels; fasting blood samples were collected twice (before STZ injection and 5 days later. The rats with their serum glucose level exceeding 250 mg/dl were considered diabetic and divided into 10 groups separately received Otostegia persica alcoholic extract (100, 200, and 300 mg/kg/day doses, glibenclamide with 600 µg/kg dose and 0.5 ml distilled water for 3 and 6 days using gavage. After 3 and 6 days, blood samples were collected again and glucose, urea, and creatinine serum levels were assessed using spectrophotometry technique by respective kits.Results: Treating diabetic rats by Otostegia persica extract (100, 200, and 300 mg/kg/day doses for 6 days results in a significant decrease of glucose and creatinine, yet an increase of serum urea with 200 mg/kg dose. Also, administration of the extract for 3 days (300 mg/kg reduced glucose, and (in various doses urea and creatinine serum levels. Conclusion: Otostegia persica extract has hypoglycemic effect and administering it in diabetes mellitus not only had no undesirable renal side effects, but also improved renal function to some extent.

Interaction between seed dormancy-release mechanism, environment and seed bank strategy for a widely distributed perennial legume, Parkinsonia aculeata (Caesalpinaceae).

Science.gov (United States)

Van Klinken, Rieks D; Lukitsch, Bert; Cook, Carly

2008-08-01

Parkinsonia aculeata (Caesalpinaceae) is a perennial legume with seeds that have hard-seeded (physical) dormancy and are potentially very long-lived. Seed dormancy is a characteristic that can both help maximize the probability of seedling establishment and spread the risk of recruitment failure across years (bet-hedging). In this study, dormancy-release patterns are described across the diverse environments in which this species occurs in order to test whether wet heat (incubation under wet, warm-to-hot, conditions) alone can explain those patterns, and in order to determine the likely ecological role of physical dormancy across this species distribution. A seed burial trial was conducted across the full environmental distribution of P. aculeata in Australia (arid to wet-dry tropics, uplands to wetlands, soil surface to 10 cm deep). Wet heat explained the pattern of dormancy release across all environments. Most seeds stored in the laboratory remained dormant throughout the trial (at least 84 %). Dormancy release was quickest for seeds buried during the wet season at relatively high rainfall, upland sites (only 3 % of seeds remained dormant after 35 d). The longest-lived seeds were in wetlands (9 % remained dormant after almost 4 years) and on the soil surface (57 % after 2 years). There was no consistent correlation between increased aridity and rate of dormancy release. The results suggest that physical dormancy in P. aculeata is a mechanism for maximizing seedling establishment rather than a bet-hedging strategy. However, seed persistence can occur in environmental refuges where dormancy-release cues are weak and conditions for germination and establishment are poor (e.g. under dense vegetation or in more arid micro-environments) or unsuitable (e.g. when seeds are inundated or on the soil surface). Risks of recruitment failure in suboptimal environments could therefore be reduced by inter-year fluctuations in microclimate or seed movement.

Physiological characteristics and related gene expression of after-ripening on seed dormancy release in rice.

Science.gov (United States)

Du, W; Cheng, J; Cheng, Y; Wang, L; He, Y; Wang, Z; Zhang, H

2015-11-01

After-ripening is a common method used for dormancy release in rice. In this study, the rice variety Jiucaiqing (Oryza sativa L. subsp. japonica) was used to determine dormancy release following different after-ripening times (1, 2 and 3 months). Germination speed, germination percentage and seedling emergence increased with after-ripening; more than 95% germination and 85% seedling emergence were observed following 1 month of after-ripening within 10 days of imbibition, compared with rice dormancy release. Dormancy release by after-ripening is mainly correlated with a rapid decline in ABA content and increase in IAA content during imbibition. Subsequently, GA(1)/ABA, GA(7)/ABA, GA(12)/ABA, GA(20)/ABA and IAA/ABA ratios significantly increased, while GA(3)/ABA, GA(4)/ABA and GAs/IAA ratio significantly decreased in imbibed seeds following 3 months of after-ripening, thereby altering α-amylase activity during seed germination. Peak α-amylase activity occurred at an earlier germination stage in after-ripened seeds than in freshly harvested seeds. Expression of ABA, GA and IAA metabolism genes and dormancy-related genes was regulated by after-ripening time upon imbibition. Expression of OsCYP707A5, OsGA2ox1, OsGA2ox2, OsGA2ox3, OsILR1, OsGH3-2, qLTG3-1 and OsVP1 increased, while expression of Sdr4 decreased in imbibed seeds following 3 months of after-ripening. Dormancy release through after-ripening might be involved in weakening tissues covering the embryo via qLTG3-1 and decreased ABA signalling and sensitivity via Sdr4 and OsVP1. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

Biological methods for assessment of budbreak in apple trees for modeling dormancy

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Rafael Anzanello

2014-06-01

Full Text Available A biological method was developed to evaluate the dormancy state of apple buds under controlled conditions. Cuttings (20-25 cm long of ‘Castel Gala’ and ‘Royal Gala’ were sampled during the winter period, evaluating different cold and heat regimes to induce budbreak. Contrasts were tested in plant material processing (single node x intact cuttings, cold storage method to break dormancy in incubator chambers (planted in pots with floral foam x wrapped in plastic film, vertically or horizontally and budbreak method in plant growth chambers (base immersed in water x planted in floral foam. Intact cuttings stored vertically in the cold represented better the natural interactions between buds than single node cuttings. Budbreak of lateral buds was strongly influenced by apical dominance. Wrapping cuttings in plastic film optimized internal space usage in the incubators and the number of evaluated buds, compared to planting cuttings in pots. During the warm period in the growth chambers, intact cuttings on floral foam resulted in better bud preservation and survival throughout the evaluation period, compared to cuttings with bases immersed in water. The most suitable conditions to evaluate dormancy evolution in apple buds used plastic-wrapped intact cuttings stored vertically during the cold period, with budbreak evaluation in the warm period after planting the cuttings in floral foam. Standardization of methodology helps to obtain better results in the development of physiological models of dormancy.

Influence of Salvadora persica (miswak) extract on physical and antimicrobial properties of glass ionomer cement

NARCIS (Netherlands)

El-Tatari, A.; de Soet, J.J.; de Gee, A.J.; Abou Shelib, M.; van Amerongen, W.E.

2011-01-01

AIM: To investigate physical and antimicrobial properties of Glass Ionomer Cement (GIC) combined with Salvadora Persica Extract (SPE). METHODS: SPE was added to GIC (Fuji IX) in concentrations of 1%, 2% and 4% w/w. The compressive strength and diametral tensile strength were measured at 1 h, 24 h

Infection of potato plants with potato leafroll virus changes attraction and feeding behaviour of Myzus persicae

NARCIS (Netherlands)

Alvarez, A.E.; Garzo, E.; Verbeek, M.; Vosman, B.; Dicke, M.; Tjallingii, W.F.

2007-01-01

Potato leafroll virus (PLRV; genus Polerovirus, family Luteoviridae) is a persistently transmitted circulative virus that depends on aphids for spreading. The primary vector of PLRV is the aphid Myzus persicae (Sulzer) (Homoptera: Aphididae). Solanum tuberosum L. potato cv. Kardal (Solanaceae) has a

Molecular characterization of the plum collection [Prunus domestica ...

African Journals Online (AJOL)

Eight Random Amplified Microsatellite markers (RAMs) were used to characterize the genetic diversity found in 14 Prunus materials belonging to the deciduous collection of the Pedagogical and Technological University of Colombia. A total of 121 bands were generated: they range from nine for the GT primer to 26 for the ...

Dormancy break in Pithecellobium dulce (Roxb. Benth. seeds

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Francisco Elder Carlos Bezerra Pereira

2015-02-01

Full Text Available This research aimed to evaluate different methods for breaking dormancy in seeds of Pithecellobium dulce (Roxb. Benth., arboreal species of multiple use in the semiarid region of Northeast Brazil. The treatments were: control – intact seeds (T1; immersion in water until it reaches 80 °C (T2, and 100 °C (T3, concentrated sulfuric acid for five minutes (T4, 10 minutes (T5 , and 15 minutes (T6, mechanical scarification with sandpaper number 80 (T7, mechanical scarification with sandpaper number 80 + immersion in water for six hours (T8, and for 12 hours (T9, soaking in water for 24 hours (T10, and for 48 hours (T11. The characteristics evaluated were such: emergency, mean emergency time, shoot length, root length, number of leaves, leaf area and total dry matter. The best method for breaking dormancy of seeds of Pithecellobium dulce (Roxb. Benth. is mechanical scarification with sandpaper number 80.

Water deficit severity during berry development alters timing of dormancy transitions in wine grape cultivar Malbec

Science.gov (United States)

The objective of this study was to test the hypothesis that vine water stress during the growing season can lengthen the dormancy cycle by inducing earlier transition into endodormancy. A bud forcing assay was used to compare the dormancy transitions of field-grown ‘Malbec’ grapevines that had been ...

Analysis of Agromorphological Descriptors to Differentiate between Duke Cherry (Prunus x gondouinii (Poit. & TurpinRehd. and Its Progenitors: Sweet Cherry (Prunus avium L. and Sour Cherry (Prunus cerasus L. Análisis de Descriptores Agromorfológicos para Diferenciar entre Cerezo Duke (Prunus x gondouinii (Poit. & Turpin Rehd. y sus Progenitores: Cerezo (Prunus avium L. y Guindo (Prunus cerasus L.

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Rodrigo Pérez

2010-03-01

Full Text Available The rapid identification of the hybrids between sweet cherry (Prunus avium L. and sour cherry (Prunus cerasus L. is not easy. In order to resolve this problem, 18 Spanish sweet, sour and duke cherry cultivars were surveyed and characterized using 43 agromorphological descriptors evaluated in flowers, leaves, dormant 1-yr-old shoots, fruits, and trees during 2005 and 2006. Based on quantitative parameters, ANOVA and stepwise discriminant analysis (SDA were carried out. For qualitative descriptors, statistical comparisons were done by means of the chi-square (χ2 test. As result of the study, two quantitative (titratable acidity and number of lenticels and six qualitative descriptors (shape of the central and lateral lobes in the internal bracts of the flower fascicles, leaf shape and margin, pubescence in the veins of the lower side of the leaf, and type of sulci of the seed coat were identified as differential parameters in P. avium, P. cerasus and P. x gondouinii(Poit. & Turpin Rehd. Also, another four qualitative descriptors (petal coloration at the end of blooming, leaf stipule type, and seed shape and viability were found to be useful for easy differentiation between sour and duke cherry. None of these parameters has been employed previously to discriminate among sweet, sour and duke cherry.Los híbridos de cerezo (Prunus avium L. y guindo (Prunus cerasus L. no son fáciles de identificar. Para resolver este problema, 18 cultivares de cerezo, guindo y sus híbridos fueron prospectados y caracterizados agromorfológicamente mediante el estudio de 43 descriptores evaluados en flores, hojas, frutos, ramas de 1 año y árbol durante los años 2005 y 2006. En base a los resultados obtenidos del estudio de los diferentes parámetros cuantitativos se realizaron un ANDEVA y un análisis discriminante escalonado (SDA. Los descriptores cualitativos fueron analizados mediante el test de Chi-cuadrado (χ². Como resultado del estudio se identificaron

Slaat Xanthomonas dit jaar weer toe in Prunus laurocerasus

NARCIS (Netherlands)

Doorn, van J.; Dalfsen, van P.; Pham, K.T.K.

2012-01-01

Een diagnostische test moet duidelijk maken of er sprake is van Xanthomonas in Prunus laurocerasus. De bacterieziekte is namelijk makkelijk te verwarren met andere ziekten. Onderzoek, gefinancierd door het Productschap Tuinbouw, richt zich op het toetsen van moerplanten voordat hier van gestekt gaat

Incorporating microbial dormancy dynamics into soil decomposition models to improve quantification of soil carbon dynamics of northern temperate forests

Energy Technology Data Exchange (ETDEWEB)

He, Yujie [Purdue Univ., West Lafayette, IN (United States). Dept. of Earth, Atmospheric, and Planetary Sciences; Yang, Jinyan [Univ. of Georgia, Athens, GA (United States). Warnell School of Forestry and Natural Resources; Northeast Forestry Univ., Harbin (China). Center for Ecological Research; Zhuang, Qianlai [Purdue Univ., West Lafayette, IN (United States). Dept. of Earth, Atmospheric, and Planetary Sciences; Purdue Univ., West Lafayette, IN (United States). Dept. of Agronomy; Harden, Jennifer W. [U.S. Geological Survey, Menlo Park, CA (United States); McGuire, Anthony D. [Alaska Cooperative Fish and Wildlife Research Unit, U.S. Geological Survey, Univ. of Alaska, Fairbanks, AK (United States). U.S. Geological Survey, Alaska Cooperative Fish and Wildlife Research Unit; Liu, Yaling [Purdue Univ., West Lafayette, IN (United States). Dept. of Earth, Atmospheric, and Planetary Sciences; Wang, Gangsheng [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Climate Change Science Inst. and Environmental Sciences Division; Gu, Lianhong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division

2015-11-20

Soil carbon dynamics of terrestrial ecosystems play a significant role in the global carbon cycle. Microbial-based decomposition models have seen much growth recently for quantifying this role, yet dormancy as a common strategy used by microorganisms has not usually been represented and tested in these models against field observations. Here in this study we developed an explicit microbial-enzyme decomposition model and examined model performance with and without representation of microbial dormancy at six temperate forest sites of different forest types. We then extrapolated the model to global temperate forest ecosystems to investigate biogeochemical controls on soil heterotrophic respiration and microbial dormancy dynamics at different temporal-spatial scales. The dormancy model consistently produced better match with field-observed heterotrophic soil CO₂ efflux (R_H) than the no dormancy model. Our regional modeling results further indicated that models with dormancy were able to produce more realistic magnitude of microbial biomass (<2% of soil organic carbon) and soil R_H (7.5 ± 2.4 PgCyr^-1). Spatial correlation analysis showed that soil organic carbon content was the dominating factor (correlation coefficient = 0.4-0.6) in the simulated spatial pattern of soil R_H with both models. In contrast to strong temporal and local controls of soil temperature and moisture on microbial dormancy, our modeling results showed that soil carbon-to-nitrogen ratio (C:N) was a major regulating factor at regional scales (correlation coefficient = -0.43 to -0.58), indicating scale-dependent biogeochemical controls on microbial dynamics. Our findings suggest that incorporating microbial dormancy could improve the realism of microbial-based decomposition models and enhance the integration of soil experiments and mechanistically based modeling.

Role of the lens in controlling physical dormancy break and germination of Delonix regia (Fabaceae: Caesalpinioideae).

Science.gov (United States)

Jaganathan, G K; Wu, G-R; Han, Y-Y; Liu, B L

2017-01-01

Physical dormancy occurs in all three subfamilies of Fabaceae, namely Mimosoideae, Papilionoideae and Caesalpinioideae, making it one of the largest plant families in terms of number of species with physical dormancy. However, little is known about the water gap structure and germination ecology of species in Caesalpinioideae. Freshly collected seeds of Delonix regia (Caesalpinioideae) did not imbibe water, thus they had physical dormancy. Both dry heat and wet heat were effective in breaking dormancy, however, longer duration was required at 80 °C and shorter duration at 90 °C. Seeds buried in the field for 2 years germinated to 21% and 42% after the first and second summer, respectively, compared with 3% germination in seeds at the time of maturity. Seeds incubated at 15/60 °C in the laboratory (mimicking summer conditions) for 3 months supported this conclusion, as dormancy was relieved in 18% and 24% of seeds stored dry and watered intermediately, respectively. All the dormancy breaking treatments resulted in lifting of palisade layers in the lens region to form a circular lid-like opening, i.e. water gap (Type II simple). Blocking experiments confirmed that water entered only through the lens and no secondary water entry point was observed. No apparent changes in morphology/anatomy of the hilum region were noted in dormant and non-dormant (water permeable) seeds. These results suggest that summer temperatures could open the lens in a proportion of seeds every year and that germination occurs during the subsequent wet season in the tropics. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

Breaking Dormancy In Gmelina arborea Roxb. Through Treatment ...

African Journals Online (AJOL)

Seeds of Gmelina arborea Roxb. were subjected to different treatment [chemical scarification with concentrated sulphuric acid (H2S04), potasium nitrate (KNO3), potasium nitrite (KNO2) and alternating temperature regimes] to ascertain the best treatment for terminating dormancy in the seeds. Initial viability and germination ...

Antioxidant effect of aqueous extract of four plants with therapeutic potential on gynecological diseases; Semen persicae, Leonurus cardiaca, Hedyotis diffusa, and Curcuma zedoaria.

Science.gov (United States)

Ji, Shaojian; Fattahi, Amir; Raffel, Nathalie; Hoffmann, Inge; Beckmann, Matthias W; Dittrich, Ralf; Schrauder, Michael

2017-11-25

Little information is available concerning antioxidant effects of plant teas (water boiled) which are used more commonly in traditional Chinese medicine than other extracts. Thus, we addressed this issue by evaluating the ability of teas from four different plants with therapeutic potential on gynecological diseases. The aqueous extracts of Semen persicae, Leonurus cardiaca, Hedyotis diffusa, and Curcuma zedoaria rhizome were prepared and then their effects on copper-induced low-density lipoprotein cholesterol (LDL-C) oxidation were evaluated by spectrophotometric method. Density gradient ultracentrifugation method was recruited to isolate LDL-C from healthy individuals. Our results showed that adding 10, 20, and 30 µl S. persicae could increase the lag phase duration of LDL-C oxidation compared with control reaction 12, 21, and 33%, respectively. The most effective delay (87%) was observed when 30 µl H. diffusa was added to the reaction. In cases of L. cardiaca and C. zedoaria, we found no significant influence on the lag phase duration (p > 0.05). Moreover, our findings about starting point of the decomposition phase were almost in parallel with the lag phase results, as 30 µl of S. persicae or H. diffusa teas could significantly increase the initiation time of decomposition (p < 0.05). In conclusion our results showed that both S. persicae and H. diffusa teas and not L. cardiaca and C. zedoaria could have medicinal therapeutic effects partly through direct oxidation prevention.

Carbohydrate metabolism during potato tuber dormancy and sprouting

NARCIS (Netherlands)

Claassens, M.M.J.

2002-01-01

Potato tuber dormancy is part of the vegetative life cycle of potato. It refers to a period, in which no growth is occurring, although the tuber is stored under conditions that are favourable for growth. Factors in the tuber are responsible for this growth arrest; soon