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1.
Bot Stud ; 65(1): 6, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38347314

RESUMO

Tecoma stans is a widely distributed tall ornamental shrub in the plains of Indian subcontinent and is considered an invasive species across Argentina, Australia, South Africa, Pacific Islands and tropical regions of Asia. Besides having an ornamental significance, T. stans has been extensively investigated for its pharmaceutical applications as a source of bioactive compounds. In addition, the shrub is cultivated commercially as a potted flowering plant. We believe that T. stans, being a hardy, invasive and aggressively growing species, holds a considerable potential and a promising solution for re-greening waste and degraded lands outside its invasive range, due to its wider adaptability and drought tolerant characteristics. The shrub is an excellent source of pollen and nectar, that attracts diverse insect-pollinators and several species of birds. The prudent plantation of this shrub has the potential to restore the ecology of barren landscapes, that can change its perspective of 'being invasive' to 'being ecologically healthy' across the tropical, semi-arid and subtropical regions worldwide. This paper reviews the current updates on ecology, life cycle including morphology, plant growth characteristics, flowering phenology, reproductive biology, breeding system and fruiting of T. stans. In addition, details on insect-pollinator diversity and natural regeneration potential have also been discussed, besides highlighting its therapeutic and landscape use.

3.
Plant J ; 104(1): 200-214, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32645755

RESUMO

The development of improved plant nucleotide-binding, leucine-rich repeat (LRR) immune receptors (NLRs) has mostly been based on random mutagenesis or on structural information available for specific receptors complexed with the recognized pathogen effector. Here, we use a targeted mutagenesis approach based on the natural diversity of the Pm3 powdery mildew resistance alleles present in different wheat (Triticum aestivum) genotypes. In order to understand the functional importance of the amino acid polymorphisms between the active immune receptor PM3A and the inactive ancestral variant PM3CS, we exchanged polymorphic regions and residues in the LRR domain of PM3A with the corresponding segments of PM3CS. These novel variants were functionally tested for recognition of the corresponding AVRPM3A2/F2 avirulence protein in Nicotiana benthamiana. We identified polymorphic residues in four regions of PM3A that enhance the immune response, but also residues that reduce it or result in complete loss of function. We found that the identified critical residues in PM3A modify its activation threshold towards different protein variants of AVRPM3A2/F2 . PM3A variants with a lowered threshold gave a stronger overall response and gained an extended recognition spectrum. One of these variant proteins with a single amino acid change was stably transformed into wheat, where it conferred race-specific resistance to mildew. This is a proof of concept that improved PM3A variants with an enlarged recognition spectrum can be engineered based on natural diversity by exchanging single or multiple residues that modulate resistance function.


Assuntos
Proteínas NLR/genética , Imunidade Vegetal/genética , Proteínas de Plantas/genética , Triticum/imunologia , Proteínas NLR/fisiologia , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas , Polimorfismo de Nucleotídeo Único/genética , Triticum/genética
4.
Int J Radiat Biol ; 96(10): 1309-1316, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32659144

RESUMO

PURPOSE: The novelty in flower color or inflorescence form is recognized as a valuable trait in Chrysanthemum - a potential commercial flower crop with significant worth in global cut flower trade. This study was conducted to irradiate white and orange flowered cultivars of Chrysanthemum with an objective to identify and isolate desirable types representing novelty in flower color and inflorescence form from the irradiated populations. The terminal rooted cuttings of Chrysanthemum exposed to γ-irradiation at 10 or 15 Gy doses were found effective for inducing novel flower color variants in cultivars Thiching Queen and Purnima. The mutant progeny evolved with novel inflorescence traits of these cultivars will enrich the existing germplasm of Chrysanthemum for further utilization in breeding programs. MATERIALS AND METHODS: Two standard type Chrysanthemum cultivars, Thiching Queen and Purnima were exposed to varied doses of γ-rays (0, 5, 10, 15, and 20 Gy) using Cobalt 60 (60Co) as irradiation source for treating rooted cuttings. The irradiated mutant population was evaluated for likely variation in various vegetative and flowering characters compared to non-irradiated (control) plants. RESULTS: In Chrysanthemum cultivars Thiching Queen, seven and 'in Purnima', two flower color variants were isolated from the irradiated populations that were reportedly novel in color and desirable for commercial aspect. The leaf abnormalities were observed in mutant populations exhibiting variation in flower color, shape, and size of leaves. Certain floral abnormalities were also observed in inflorescence that reportedly progressed with increase in dosage of γ-rays irradiation. CONCLUSIONS: This study developed a gamma ray (60Co) induced mutagenesis protocol with potential application to develop novel and desirable mutants in Chrysanthemum.


Assuntos
Chrysanthemum/efeitos da radiação , Radioisótopos de Cobalto/efeitos adversos , Raios gama/efeitos adversos , Inflorescência/efeitos da radiação , Chrysanthemum/crescimento & desenvolvimento , Chrysanthemum/metabolismo , Relação Dose-Resposta à Radiação , Inflorescência/crescimento & desenvolvimento , Inflorescência/metabolismo , Dose Letal Mediana , Pigmentação/efeitos da radiação
5.
Plant Mol Biol ; 98(3): 249-260, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30244408

RESUMO

KEY MESSAGE: We have isolated a novel powdery mildew resistance gene in wheat that was originally introgressed from rye. Further analysis revealed evolutionary divergent history of wheat and rye orthologous resistance genes. Wheat production is under constant threat from a number of fungal pathogens, among them is wheat powdery mildew (Blumeria graminis f. sp. tritici). Deployment of resistance genes is the most economical and sustainable method for mildew control. However, domestication and selective breeding have narrowed genetic diversity of modern wheat germplasm, and breeders have relied on wheat relatives for enriching its gene pool through introgression. Translocations where the 1RS chromosome arm was introgressed from rye to wheat have improved yield and resistance against various pathogens. Here, we isolated the Pm17 mildew resistance gene located on the 1RS introgression in wheat cultivar 'Amigo' and found that it is an allele or a close paralog of the Pm8 gene isolated earlier from 'Petkus' rye. Functional validation using transient and stable transformation confirmed the identity of Pm17. Analysis of Pm17 and Pm8 coding regions revealed an overall identity of 82.9% at the protein level, with the LRR domains being most divergent. Our analysis also showed that the two rye genes are much more diverse compared to the variants encoded by the Pm3 gene in wheat, which is orthologous to Pm17/Pm8 as concluded from highly conserved upstream sequences in all these genes. Thus, the evolutionary history of these orthologous loci differs in the cereal species rye and wheat and demonstrates that orthologous resistance genes can take different routes towards functionally active genes. These findings suggest that the isolation of Pm3/Pm8/Pm17 orthologs from other grass species, additional alleles from the rye germplasm as well as possibly synthetic variants will result in novel resistance genes useful in wheat breeding.


Assuntos
Evolução Biológica , Variação Genética , Proteínas de Plantas/metabolismo , Secale/genética , Triticum/genética , Predisposição Genética para Doença , Especiação Genética , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética
6.
Vet Comp Orthop Traumatol ; 31(5): 373-378, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30125912

RESUMO

OBJECTIVE: Study included surgical management of radius and ulna fracture in a 2-year-old, 220 kg crossbred heifer presented with a 2-day-old history of injury resulting in severe, non-weight bearing lameness of the left forelimb. METHODS: The condition was diagnosed clinically and confirmed radiographically as a middle third oblique comminuted fracture of the left radius and ulna. Static intramedullary interlocking nailing was performed for fracture fixation. An interlocking nail of 12-mm diameter and 26-cm length was introduced in a retrograde manner from the distal aspect of the radius. RESULTS: The animal was able to bear weight on the affected limb within 7 days post surgery. Good callus formation and complete weight bearing were observed by 35th day. Bending of the screws and osteophytic reaction were the major postoperative complications observed radiographically. CLINICAL SIGNIFICANCE: From this case study, it was established that static intramedullary interlocking nailing can be used as an alternative technique for fracture repair of the radius and ulna in cattle where stable fracture fixation by bone plating is questionable.


Assuntos
Bovinos/lesões , Fixação Intramedular de Fraturas/veterinária , Fraturas do Rádio/veterinária , Fraturas da Ulna/veterinária , Animais , Pinos Ortopédicos/veterinária , Bovinos/cirurgia , Feminino , Fixação Intramedular de Fraturas/instrumentação , Fixação Intramedular de Fraturas/métodos , Radiografia/veterinária , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Fraturas da Ulna/diagnóstico por imagem , Fraturas da Ulna/cirurgia
7.
Sci Rep ; 7(1): 6883, 2017 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-28761150

RESUMO

Nearly half of the world's population obtains its daily calories from rice grains, which lack or have insufficient levels of essential micronutrients. The deficiency of micronutrients vital for normal growth is a global health problem, and iron, zinc and vitamin A deficiencies are the most prevalent ones. We developed rice lines expressing Arabidopsis NICOTIANAMINE SYNTHASE 1 (AtNAS1), bean FERRITIN (PvFERRITIN), bacterial CAROTENE DESATURASE (CRTI) and maize PHYTOENE SYNTHASE (ZmPSY) in a single genetic locus in order to increase iron, zinc and ß-carotene content in the rice endosperm. NAS catalyzes the synthesis of nicotianamine (NA), which is a precursor of deoxymugeneic acid (DMA) iron and zinc chelators, and also chelate iron and zinc for long distance transport. FERRITIN provides efficient storage of up to 4500 iron ions. PSY catalyzes the conversion of GGDP to phytoene, and CRTI performs the function of desaturases required for the synthesis of ß-carotene from phytoene. All transgenic rice lines have significantly increased ß-carotene, iron, and zinc content in the polished rice grains. Our results establish a proof-of-concept for multi-nutrient enrichment of rice grains from a single genetic locus, thus offering a sustainable and effective approach to address different micronutrient deficiencies at once.


Assuntos
Alquil e Aril Transferases/genética , Ferritinas/genética , Geranil-Geranildifosfato Geranil-Geraniltransferase/genética , Micronutrientes/metabolismo , Oryza/crescimento & desenvolvimento , Oxirredutases/genética , Alquil e Aril Transferases/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , Bactérias/enzimologia , Bactérias/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Fabaceae/genética , Fabaceae/metabolismo , Ferritinas/metabolismo , Loci Gênicos , Geranil-Geranildifosfato Geranil-Geraniltransferase/metabolismo , Ferro/metabolismo , Oryza/genética , Oryza/metabolismo , Oxirredutases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Zea mays/enzimologia , Zea mays/genética , Zinco/metabolismo , beta Caroteno/metabolismo
8.
Theor Appl Genet ; 130(2): 283-292, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27722771

RESUMO

KEY MESSAGE: Iron and zinc deficiencies negatively impact human health worldwide. We developed wheat lines that meet or exceed recommended dietary target levels for iron and zinc in the grains. These lines represent useful germplasm for breeding new wheat varieties that can reduce iron and zinc deficiency-associated health burdens in the affected populations. Micronutrient deficiencies, including iron and zinc deficiencies, have negative impacts on human health globally. Iron-deficiency; anemia affects nearly two billion people worldwide and is the cause of reduced cognitive development, fatigue and overall low productivity. Similarly, zinc deficiency causes stunted growth, decreased immunity and increased risk of respiratory infections. Biofortification of staple crops is a sustainable and effective approach to reduce the burden of health problems associated with micronutrient deficiencies. Here, we developed wheat lines expressing rice NICOTIANAMINE SYNTHASE 2 (OsNAS2) and bean FERRITIN (PvFERRITIN) as single genes as well as in combination. NAS catalyzes the biosynthesis of nicotianamine (NA), which is a precursor of the iron chelator deoxymugeneic acid (DMA) required for long distance iron translocation. FERRITIN is important for iron storage in plants because it can store up to 4500 iron ions. We obtained significant increases of iron and zinc content in wheat grains of plants expressing either OsNAS2 or PvFERRTIN, or both genes. In particular, wheat lines expressing OsNAS2 greatly surpass the HarvestPlus recommended target level of 30 % dietary estimated average requirement (EAR) for iron, and 40 % of EAR for zinc, with lines containing 93.1 µg/g of iron and 140.6 µg/g of zinc in the grains. These wheat lines with dietary significant levels of iron and zinc represent useful germplasm for breeding new wheat varieties that can reduce micronutrient deficiencies in affected populations.


Assuntos
Alquil e Aril Transferases/genética , Ferro da Dieta/análise , Oryza/enzimologia , Sementes/química , Triticum/genética , Zinco/análise , Ferritinas/genética , Farinha/análise , Micronutrientes/análise , Oryza/genética , Phaseolus/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Transgenes
9.
Ecotoxicology ; 19(2): 338-50, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19779818

RESUMO

The common occurrence of human derived contaminants like pharmaceuticals, steroids and hormones in surface waters has raised the awareness of the role played by the release of treated or untreated sewage in the water quality along sensitive coastal ecosystems. South Florida is home of many important protected environments ranging from wetlands to coral reefs which are in close proximity to large metropolitan cities. Because, large portions of South Florida and most of the Florida Keys population are not served by modern sewage treatment plants and rely heavily on the use of septic systems, a comprehensive survey of selected human waste contamination markers was conducted in three areas to assess water quality with respect to non-traditional micro-constituents. This study documents the occurrence and distribution of fifteen hormones and steroids and five commonly detected pharmaceuticals in surface water samples collected from different near shore environments along South Florida between 2004 and 2006. The compounds most frequently detected were: cholesterol, caffeine, estrone, DEET, coprostanol, biphenol-A, beta-estradiol, and triclosan. The concentration detected for estrone and beta-estradiol were up to 5.2 and 1.8 ng/L, respectively. Concentrations of caffeine (5.5-68 ng/L) and DEET (4.8-49 ng/L) were generally higher and more prevalent than were the steroids. Distribution of microconstituents was site specific likely reflecting a diversity of sources. In addition to chemical analysis, the yeast estrogen screen assay was used to screen the samples for estrogen equivalency. Overall, the results show that water collected from inland canals and restricted circulation water bodies adjacent to heavily populated areas had high concentrations of multiple steroids, pharmaceuticals, and personal care products while open bay waters were largely devoid of the target analytes.


Assuntos
Ecossistema , Monitoramento Ambiental , Hormônios/análise , Preparações Farmacêuticas/análise , Esgotos/análise , Esteroides/análise , Poluentes Químicos da Água/análise , Bioensaio , Estrogênios/análise , Estrogênios/metabolismo , Florida , Preparações Farmacêuticas/química , Medição de Risco , Rios/química , Água do Mar/química , Esgotos/química , Fatores de Tempo , Poluentes Químicos da Água/química
10.
Vet Radiol Ultrasound ; 49(3): 295-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18546788

RESUMO

The study was conducted to establish the ultrasonographic features of the healthy and impacted omasum in cows and buffaloes. Scanning was done using a 3.5 MHz microconvex transducer. In healthy buffaloes, the omasum could be scanned at the eighth to ninth intercostal space as a round or oval structure having thick echogenic wall with echogenic leaves. Gradual slow movements of omasal leaves could also be seen in real-time B-mode. The omasum appeared to be very clear, large, and close to the transducer at the start of the omasal contraction, and as the contraction progressed the omasum retracted away from the transducer and became very small. In healthy cows the omasum was seen as a crescent-shaped structure with an echogenic wall. The contents of the omasum or omasal leaves could not be visualized. Omasal contractility was not as prominent as in buffaloes. In buffaloes, the impacted omasum appeared amotile, the omasal leaves were not visible, and the omasum as a whole gave a prominent distal acoustic shadow. In cows, the impaction could be diagnosed based on amotile omasum covering a large area on the right side. Ultrasonography was found to be helpful in subjective assessment of omasal impaction but could not aid in diagnosing the severity of impaction.


Assuntos
Búfalos/anatomia & histologia , Doenças dos Bovinos/diagnóstico por imagem , Bovinos/anatomia & histologia , Constrição Patológica/veterinária , Gastroenteropatias/veterinária , Omaso , Animais , Estudos de Casos e Controles , Constrição Patológica/diagnóstico por imagem , Feminino , Gastroenteropatias/diagnóstico por imagem , Omaso/anatomia & histologia , Omaso/diagnóstico por imagem , Índice de Gravidade de Doença , Ultrassonografia
11.
Water Res ; 40(3): 588-94, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16443254

RESUMO

1-Aminopropanone (APR) is a volatile aminoketone of human origin that has been identified in raw sewage and surface waters. However, the traditional methodology for the determination of APR is extremely complicated and requires a skilled chemist to achieve consistent results. This investigation presents a novel and simple method for the analysis of APR by direct derivatization in aqueous media. APR is synthesized as its hydrochloride and derivatized using mercaptoethanol and o-phthalaldehyde. The product of reaction is separated on a 15 cm x 4.6 mm Luna C-18 column (1 mL/min, 45:55 acetonitrile: Water) and detected using a single quadrupole mass spectrometer detector operated in atmospheric pressure chemical ionization (APCI) mode. Method detection limits as low as 100 nM were routinely obtained with a precision of 1.7%. Recoveries of APR were always found to be greater then 88% in surface and wastewater samples fortified at three different levels. However, despite the robustness of the method and the fact that APR was consistently detected in urine it was not present in a variety surface or wastewaters analyzed during the course of the study. These results pose a critical question on the use of APR as a tracer for human derived wastewaters.


Assuntos
Acetona/análogos & derivados , Propanolaminas/análise , Eliminação de Resíduos Líquidos/normas , Acetona/análise , Cromatografia Líquida , Monitoramento Ambiental/métodos , Humanos , Espectrometria de Massas , Sensibilidade e Especificidade , Esgotos/química , Urinálise
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