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General guidelines for statistically sound and risk-based surveys of plant pests
Get PDFAt the request of the European Commission, EFSA prepared the general guidelines for surveys of plant pests, describing the legal, international and scientific context in which the surveys are designed, the basic principles implemented for surveillance of quarantine pests and introducing the concepts needed for the design of statistically sound and risk-based surveys. Three types of specific surveys are addressed: detection surveys for substantiation of pest freedom, delimiting surveys for determining the boundaries of an infested zone, and monitoring surveys for prevalence estimation when measuring the progress of eradication measures or for confirming a low pest prevalence area. For each survey, the survey parameters are introduced and their interactions analysed showing the importance of the assumptions that are taken for each one of them: (i) the aims of the survey are defined as the confidence of detecting a given pest prevalence (design prevalence), this reflects the trade-off between the acceptable level of the risk and availability of resources that determine the strength of the evidence to support the conclusion of the survey; (ii) the target population is addressed in terms of its structure and size, including the risk factors; and (iii) the method sensitivity is defined as the combination of the sampling effectiveness and the diagnostic sensitivity. EFSA’s RiBESS+ tool is introduced for calculating the sample size using the survey parameters as input values for a statistically sound and risk-based survey design. The mathematical principles behind the tool are in line with the International Standards for Phytosanitary Measures. The survey design is flexible and can be tailored to each pest and specific situation in the Member States. Once the survey is implemented following this approach, the conclusions allow surveys to be compared across time and space, contributing to the harmonisation of surveillance activities across the EU Member States
Estudio plurianual del efecto del régimen hídrico sobre la composición nitrogenada de las variedades blancas Cigüente, Macabeo, Moscatel de Alejandría y Verdejo, cultivadas en diversas regiones de España
Get PDFEste trabajo analiza el efecto del régimen hídrico y del año sobre el perfil
aminoacídico y el amonio de diferentes variedades blancas, conducidas en espaldera, en
diferentes zonas vitícolas españolas. Las variedades, la localización y los tratamientos
aplicados fueron: Cigüente (Ci) en Badajoz, secano y riego al 100% de ETc; Macabeo
(Ma) en Albacete, 25% y 33% aprox de ETc; Moscatel de Alejandría (Mo) en Valencia,
50% y 100% de ETc; y Verdejo (Ve) en Valladolid, secano y 100% aprox. de ETc. En
vendimia se analizó la composición aminoacídica y el amonio de la uva mediante HPLC
y se calcularon el CTA (Contenido Amínico Total, mgL-1), aminoácidos asimilables (AA,
mgL-1) y el YAN (Nitrógeno Fácilmente Asimilable por las levaduras). En Ci, Ma y Ve
se hallaron diferencias significativas entre tratamientos para la mayoría de los
aminoácidos. Debido a la variabilidad climática interanual observada, en la mayoría de
ellos se encontró interacción significativa tratamiento*año, especialmente en Ci y Ma. La
variación interanual y el efecto del riego fueron de poca amplitud y significación en Mo,
observándose descensos en los valores medios de los aminoácidos individuales y de CTA
y YAN en la uva de los tratamientos más regados. En Ma la aplicación de mayor dosis de
agua durante el preenvero provocó aumentos en la mayoría de los aminoácidos, de mayor
amplitud en 2014. En Ci la tendencia, amplitud y significación del efecto tratamiento
dependió incluso de la campaña analizada para un determinado aminoácido. El riego en
Ve disminuyó la concentración de los aminoácidos presentes en las bayas. Aunque no se
ha logrado establecer un grupo de aminoácidos común para todas las variedades que
pudieran servir de indicadores del estado hídrico de la cepa, los resultados hallados en Ci
y Ve sugieren la existencia de patrones comunes para determinados grupos de variedades
cuando los estados hídricos son similares
Specific Real-Time PCR for the Detection and Absolute Quantitation of Grapevine Roditis Leaf Discoloration-Associated Virus, an EPPO Alert Pathogen
Get PDFGrapevine Roditis leaf discoloration-associated virus (GRLDaV) is an emerging grapevine pathogen included in the European and Mediterranean Plant Protection Organization (EPPO) alert list due to its ability to damage grapevine crops and cause production losses. This work aimed to develop a specific and reliable diagnostic tool that would contribute to preventing the spread of this pathogen. Therefore, a TaqMan real-time quantitative PCR was developed. The method was validated according to EPPO guidelines showing a high degree of analytical sensitivity, analytical specificity, selectivity, and repeatability and reproducibility. The sensitivity of this method is much higher than the sensitivity reached by previously reported methods even when tested in crude extracts, which could allow rapid testing by avoiding nucleic acid extraction steps. The method was also able to detect GRLDaV isolates from all the geographic origins reported so far, despite their high degree of genetic diversity. In addition, this new technique has been successfully applied for the quantitative detection of GRLDaV in plant material and two mealybug species, Planococcus citri and Pseudococcus viburni. In conclusion, the methodology developed herein represents a significant contribution to the diagnosis and control of this emerging pathogen in grapevine
Partially defatted olive cake in finishing pig diets: implications on performance, faecal microbiota, carcass quality, slurry composition and gas emission
Get PDFOne of the key factors to improve swine production sustainability is the use of agro-industrial by-products in feeds, such as olive by-products. However, it is necessary to assess its effects on the overall production process, including the animal and the environment. With this aim, an experiment was conducted to determine the effects of including a partially defatted olive cake (PDOC) in pig diets on growth performance, faecal microbiota, carcass quality and gas emission from the slurry. Two finishing diets were formulated, a control (C) diet and a diet with PDOC included at 120 g/kg. Eighty finishing male pigs Duroc-Danbred × (Landrace × Large White) of 60.4 ± 7.00 kg BW were divided between these two treatments. During the finishing period (60 to 110 kg BW, 55 days) average daily gain, average daily feed intake and feed conversion ratio were recorded. Faecal samples from the rectum of 16 animals per treatment were incubated for bacteria enumeration. At the end of finishing period, backfat thickness and loin depth (LD) were measured. Animals were slaughtered to obtain carcass weight and carcass composition parameters, and subcutaneous fat was sampled to analyse the fatty acid (FA) profile. In addition greenhouse gas and ammonia emissions were measured during pig slurry storage using the methodology of dynamic flux chambers. An initial slurry characterisation and biochemical methane potential (B0) were also determined. No significant differences between treatments were found in performance, carcass quality and microbial counts with the exception of LD, which was lower in PDOC compared with C animals (45.5 v. 47.5 mm, SEM: 0.62; P = 0.020). The FA profile of the subcutaneous fat did not differ between treatments, but the monounsaturated FA (MUFA) concentration was higher and the polyunsaturated FA was lower in the animals fed PDOC (50.9 v. 48.3, SEM: 0.48, P < 0.001; 17.6 v. 19.3, SEM: 0.30, P < 0.001 in mg/100 g of Total FA, for PDOC and C animals, respectively). The initial pig slurry characterisation only showed differences in ADF concentration that was higher (P < 0.05) in the slurry from PDOC treatment. Regarding gas emission, slurries from both treatments emitted similar amounts of ammonia (NH3), carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), as well as B0 values. The results obtained suggest that PDOC may be included in balanced pig diets at rates of up to 120 g/kg without negative effects on performance, carcass quality, gut microflora and slurry gas emission, while improving the MUFA concentration of subcutaneous fat
Analysis of Virome by High-Throughput Sequencing Revealed Multiple Infection and Intra-Virus Diversity in a Single Grapevine Plant
Get PDFThe ribosomal-depleted total RNA from white-berry grapevine (Vitis vinifera, SK933) plant showing severe chlorosis and downrolling of leaves was used for the high-throughput sequencing (HTS) analysis in order to unravel the potential contribution of the viral pathogens to the symptomatology observed. The combination of de novo assembly and mapping of ca. 1.1 millions of HTS reads enabled to identify and characterise a complex viral/viroid infection involving Grapevine leafroll-associated virus-2 (GLRaV-2), Grapevine leafroll-associated virus-3 (GLRaV-3), Grapevine rupestris stem pitting-associated virus (GRSPaV), Grapevine rupestris vein feathering virus (GRVFV), Grapevine Syrah virus-1 (GSyV-1) and Hop stunt viroid (HSVd). The determined nearly complete genomes of GLRaV-2 SK933 showed its high genetic divergence from previously characterised isolates. In case of GRSPaV, two variants representing different evolutionary lineages have been identified in the plant. The results further pinpoint the complexity of grapevine viral diseases and show that mixed virus infection of grapevine is rather a rule than an exception
Eficácia dos extratos de romã no controlo de doenças pós-colheita em laranjas ‘Navelina’
Get PDFEfficacy of pomegranate extracts on controlling post-harvest diseases in
‘Navelina’ oranges
Controlling post-harvest diseases through the use of plant protection products is
becoming increasingly difficult, with strict limitations, loss of effectiveness and the
public and markets demand for less or even residue-free products.
As so, horticultural sector needs to effectively minimize post-harvest pathogenic
fungal rot losses in citrus fruits with a reduced use of plant protection products. The literature indicates that different natural extracts, such as pomegranate skin extracts, have
growth control properties of Penicillium digitatum.
The objective of this work was to verify the effectiveness of pomegranate extracts
in reducing postharvest losses of citrus fruits that Frutas Tereso markets, caused by the
main postharvest pathogenic fungus P. digitatum.
Water and methanol extracts of pomegranate skin from the varieties 'Acco'
‘Wonderful’ and 'Mollar de Elche' were obtained and secondary screening and semicommercial
testing on 'Navelina' oranges were performed.
In secondary screening in 'Navelina' oranges, treatment with aqueous extract of the
'Wonderful' pomegranate variety at a dry residue concentration of 1.2% versus control
allowed a reduction in rot incidence of over 47% at day 7 and over 37% at day 10. With
methanol solvent at a dry residue concentration of 2%, the reduction in the incidence of
decay over the control was greater than 47% at days 7 and 10. In the semi-commercial
trial, Wonderful-Methanol-2% treatment was the most effective: the reduction in
incidence, sporulation and severity with this treatment was 33%, 44% and 40%,
respectively.
Tests indicate that pomegranate extract treatments, particularly 2% 'Wonderful'
methanolic extracts, are effective in reducing the incidence, severity, and sporulation of
P. digitatum rot in 'Navelina'
Color transform to optimize fruit ripeness discrimination in dichromats
Get PDFAim: To develop and test a color transform for red-green color
defectives to enhance tomatoipeness judgements.
Experimental Method: Congenital protan and deutan color
defectives suffer sensitivity losses in the red-green mechanism [1]
compromising performance in color-discrimination-based everyday
tasks [2], which may be compensated by procedures designed to
optimize image color gamuts to minimize color confusion [3]. Given that
red-green defectives retain normal discrimination along the blue-yellow
axis in color space [1], we propose a simple procedure to recode redgreen
color differences in CIELAB color space as blue-yellow color
differences, to allow red-green defectives to correctly judge the ripeness
of tomatoes.
An agricultural cooperative of Perelló supplied and classified by
color the tomato samples in a controlled manner in four standard
ripeness stages. Sample color was measured with a portable Minolta
CR-300 colorimeter (Minolta Co. Ltd, Osaka, Japan). Tomatoes were
photographed with a Smartphone (Samsung Galaxy S7 edge model SMG935F
with a 12.2 MP camera). RGB values of the image were
transformed to XYZ values using Matlab’s sRGB transform, and then to
CIEL*a*b*, using as reference white a white sample illuminated as the
samples. Dichromatic perception of the images was simulated by the
corresponding pair algorithm [4]. The modified palette was obtained by
exchanging the values of the red-green (a*) and blue-yellow (b*)
descriptors (Fig. 1)
Effect of Grafting on the Production, Physico-Chemical Characteristics and Nutritional Quality of Fruit from Pepper Landraces
Get PDFGrafting is a widely utilized agronomical technique to improve yield, disease resistance,
and quality of fruit and vegetables. This work aims to assess the effect of grafting and fruit ripening
on the production, physico-chemical characteristics, and nutritional quality of fruit from Spanish local
pepper landraces. Landraces “Cuerno,” “Sueca,” and “Valencia” were used as scions, and “NIBER®”
as the rootstock. Two ripening stages of the fruits were sampled: green and red. Grafting improved the
yield and marketable quality and did not negatively influence the physico-chemical and nutritional
characteristics of the fruit. It was noteworthy that the bioactive compound contents and antioxidant
capacity were more related to maturity stage and genotype, and red fruit had a higher antioxidant
capacity than green fruit. However, in all the scions, grafting significantly enhanced lycopene
content in both red and green fruit. Another important effect of grafting was the volatile compound
composition evidenced by discriminant analyses, which was characterized for the first time in the
fruit of these landraces. The rootstock and scion combination could be a way to improve not only the
production, but also the fruit quality of pepper
