Relationships between nutrient composition of flowers and fruit quality in orange trees grown in calcareous soil     

Pestana M  Beja P  Correia PJ  de Varennes A  Faria EA 《Tree physiology》2005,25(6):761-767

To determine if flower nutrient composition can be used to predict fruit quality, a field experiment was conducted over three seasons (1996-1999) in a commercial orange orchard (Citrus sinensis (L.) Osbeck cv. 'Valencia Late', budded on Troyer citrange rootstock) established on a calcareous soil in southern Portugal. Flowers were collected from 20 trees during full bloom in April and their nutrient composition determined, and fruits were harvested the following March and their quality evaluated. Patterns of covariation in flower nutrient concentrations and in fruit quality variables were evaluated by principal component analysis. Regression models relating fruit quality variables to flower nutrient composition were developed by stepwise selection procedures. The predictive power of the regression models was evaluated with an independent data set. Nutrient composition of flowers at full bloom could be used to predict the fruit quality variables fresh fruit mass and maturation index in the following year. Magnesium, Ca and Zn concentrations measured in flowers were related to fruit fresh mass estimations and N, P, Mg and Fe concentrations were related to fruit maturation index. We also established reference values for the nutrient composition of flowers based on measurements made in trees that produced large (> 76 mm in diameter) fruit.  相似文献   

Growth and development of the arborescent cactus Stenocereus queretaroensis in a subtropical semiarid environment,including effects of gibberellic acid     

Pimienta E  Hernandez G  Domingues A  Nobel PS 《Tree physiology》1998,18(1):59-64

In Stenocereus queretaroensis (Weber) Buxbaum, an arborescent cactus cultivated in Jalisco, Mexico, for its fruits but studied here in wild populations, stem extension occurred in the autumn at the beginning of the dry season, flowering and fruiting occurred in the spring at the end of the dry season, and new roots grew in the summer during the wet season. The asynchrony of vegetative and reproductive growth reduces competitive sink effects, which may be advantageous for wild populations growing in infertile rocky soils. Seasonal patterns of sugars in the roots and especially the stems of S. queretaroensis were closely related to the main phenological stages, becoming lower in concentration during periods of major stem extension. Cessation of stem extension occurred in 100-year-old plants for which injection of GA(3) reinitiated such growth. Isolated chlorenchyma cylinders had maximum extension in a bathing solution containing 0.1 &mgr;M gibberellic acid.  相似文献   

Effect of CCC and daminozide on growth of silver birch container seedlings during three years after spraying     

Luoranen  Jaana  Rikala  Risto  Aphalo  Pedro J. 《New Forests》2002,23(1):71-80

Applications of growth retardants, daminozide and CCC (chlormequatchloride), were studied in order to determine their effects on morphology and post-planting growth of silver birch (Betula pendula Roth) container seedlings. Daminozide was sprayed once (on 28 June at concentrations of 1.0 – 6.0 g l^–1) and CCC was sprayed twice (on 29 June and 27 July at concentrations of 0.5–3.0 gl^–1). Height growth, morphology of seedlings at the end of the growing season, the shoot and root growth potential the following spring and field performance during the following seasons were measured. During the first summer in the nursery, both daminozide and CCC retarded height growth,but daminozide was more effective. The effects of compounds on stem diameter during the summer of application were small. Neither of the compounds affected the field performance of seedlings. The most suitable applications for retardation of height growth, without negative effects on other morphological variables, were 4 g l^–1 (32 mg per seedling) for daminozide and 2 g l^–1 (16 mg per seedling), sprayed in two applications, for CCC.  相似文献   

Field performance of silver-birch planting-stock grown at different spacing and in containers of different volume   总被引：1，自引：0，他引：1  

Aphalo  Pedro  Rikala  Risto 《New Forests》2003,25(2):93-108

Silver birch seedlings were grown in two types of trays differing incell volume. For each kind of tray, three different spacings were achieved bygrowing seedlings in all, half or one quarter of the cells. The planting-stockso produced was out-planted at two forest sites and growth followed for fiveyears. Container size had a large effect on seedling morphology and on fieldperformance. Density also had a large effect on seedling morphology, but littleinfluence on performance. The tightest relationship of field performance was tothe mean dry weight of the stems of the planting stock (R² = 0.94).Mean height and sturdiness index, defined as diameter ÷height, were not correlated with performance. Of the non-destructivemeasurements, mean root-collar diameter was the most closely correlated withperformance.  相似文献   

Reproductive and productive performances of Santa Inês ewes submitted to breeding in different periods of the Amazonian humid tropical climate     

Felipe Nogueira Soares  Maria Emilia Franco Oliveira  Luciana Cristina Padilha-Nakaghi  Luís Guilherme de Oliveira  Marcus Antônio Rossi Feliciano  Felipe Brener Bezerra de Oliveira  Pedro Paulo Maia Teixeira  Wilter Ricardo Russiano Vicente  Cristian Faturi  Luiz Fernando de Souza Rodrigues 《Tropical animal health and production》2015,47(8):1465-1471

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Alopecia areata universalis in a dog          下载免费PDF全文

Pedro J. Ginel  Beatriz Blanco  María Pérez‐Aranda  Rafael Zafra  Elena Mozos 《Veterinary dermatology》2015,26(5):379-e87

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Ultrastructural characterization of normal Merkel cells in the dog          下载免费PDF全文

Gustavo A. Ramírez  Francisco Rodríguez  Pedro Herráez  Ayoze Castro‐Alonso  Marisa Andrada  Antonio Espinosa‐de‐los‐Monteros 《Veterinary dermatology》2015,26(5):328-e69

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Biscogniauxia nummularia infecting beech (Fagus sylvatica) trees and sympatric plants of the sedge Carex brevicollis          下载免费PDF全文

I. Zabalgogeazcoa  J. Pedro  R. M. Canals 《Forest Pathology》2015,45(4):346-348

Biscogniauxia nummularia is known for its association with beech (Fagus sylvatica), on which it occurs as a saprotroph and a pathogen causing strip cankers following water stress. This fungus has also been reported as a dominant endophytic species in plants of the sedge Carex brevicollis growing in the understory of beech forests and adjacent grasslands in Sierra de Urbasa (Navarre, Spain). In this area, stromata of B. nummularia were observed in dead and living wood of beech trees at several locations where plants of C. brevicollis also contained the fungus as an endophyte. Pure cultures obtained from stromata of B. nummularia on F. sylvatica trees were compared to endophytic isolates from symptomless C. brevicollis. Culture morphology and micromorphology as well as rDNA sequences of the internal transcribed spacer (ITS) regions were identical, suggesting that B. nummularia from beech can also live endophytically in C. brevicollis. It is unknown whether the endophytic strains of Carex might have a role as an inoculum source for the infection of beech trees, or whether they represent a dead end in the life cycle of the fungus.  相似文献   

Method of determination of nitrosamines in sausages by CO2 supercritical fluid extraction (SFE) and micellar electrokinetic chromatography (MEKC)     

Sanches Filho PJ  Rios A  Valcarcel M  Melecchi MI  Caramão EB 《Journal of agricultural and food chemistry》2007,55(3):603-607

In this paper, the use of supercritical fluid extraction (SFE) and micellar electrokinetic capillary chromatography (MEKC) is proposed for the complete analysis of volatile nitrosamines in sausages. The extraction fluid used was CO2 and variables such as density, temperature of thimbles, extraction time, modifier, fluid flow, and kind of traps were investigated. Several experiments were carried out to obtain the most favorable conditions for analysis of volatile nitrosamines in sausages. The recoveries ranged from 21 to 82% for the five nitrosamines studied. The optimal condition of extraction was 0.2 g of sample fortified with 10 mg/kg, using dynamic extraction during 20 min and with adsorbent Florisil in the trap. The solvent selected for the elution of the analytes was methanol.  相似文献   

Volumetric properties of sunflower methyl ester oil at high pressure     

Aparicio C  Guignon B  Rodríguez-Antón LM  Sanz PD 《Journal of agricultural and food chemistry》2007,55(18):7394-7398

Biodiesel is an alternative to diesel oil (DO), because it is a fuel obtained from renewable resources that has lower emissions than DO. Biomass production should promote agricultural activity to obtain fuels for the transport sector. The study of the behavior of biodiesel at varying pressure and temperature is very interesting because diesel engines are mechanical systems that work with fuels submitted to high pressure. The specific volume, isothermal compressibility, and cubic expansion coefficients of refined sunflower methyl ester oil (SMEO) and unrefined sunflower methyl ester oil (URSMEO) were obtained and compared with those of DO from 0.1 to 350 MPa and 288.15 to 328.15 K. This work shows that oil refinement did not significantly modify any of the properties studied of the final biodiesel. Compared with DO, both SMEOs were about 6% denser, whereas isothermal compressibility and cubic expansion coefficients were bigger or smaller for DO depending on pressure and temperature.  相似文献