ReDivia - Repositorio Digital de l'Instit Valencià d'Investigacions Agràries
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Decision support systems halve fungicide use compared to calendar-based strategies without increasing disease risk
Get PDFThe European Green Deal aims to reduce the use of chemical pesticides by half by 2030. Decision support systems are tools to help farmers schedule fungicide spraying based on disease risk and can reduce fungicide application frequency and overall use. However, the potential benefit of decision support systems compared to traditional calendar-based strategies has not yet been rigorously quantified. Here we synthesise 80 experiments and show that globally decision support systems can reduce fungicide treatments by at least 50% without compromising disease control. For a given fixed number of fungicide sprays, decision support systems were as effective as calendar-based programs in reducing disease incidence. When the number of sprays was halved, the increase in disease incidence was lower for decision support system-based strategies than calendar-based strategies. Our findings suggest that decision support systems can reduce fungicide use while limiting the risk to plant health and resistance development
PSV-16 Effects of the Inclusion of a Capsicum Oleoresin-based Additive on Growth Performance, Carcass Composition and Meat Quality of Pigs Under Heat Stress Conditions
No full textCapsicum oleoresin has recognized effects on digestion and fat metabolism. A total of 100 PIC x Danbred female pigs were divided in two experimental groups (10 pens/group) from 60Kg body weight (BW) to slaughter: one control group (T1) and another group (T2) where the sensorial additive (350ppm) was added from 90Kg to 130Kg BW. The study was carried out in Mediterranean summer conditions. Experimental rooms turned off their cooling systems at 90Kg BW to the end of the study. Temperature and humidity were recorded using dataloggers (HOBO®). Pig BW and intake were recorded before exposure to the additive and at the end of the administration of experimental feeds. Additionally, backfat thickness (BF) and loin depth (LD) were measured. Respiration rate (RR) and rectal temperature (RT) were also recorded at 0800, 1100, 1400 and 1700h. Carcass and meat quality parameters were measured in the slaughterhouse. Data was analyzed using Proc GLM (performance, carcass and meat quality) and Proc MIXED of repeated measures (RR, RT) of SAS. Environmental data confirmed heat stress conditions for finishing pigs (THI >71 from 0800 to 2200h). Growth performance, BF and LD did not differ between groups. Animals from T2 showed higher (P< 0.05) RR and lower (P< 0.05) RT compared to T1 at 17:00h. At slaughter, animals from T2 tended (P< 0.10) to have a higher fat content (3-4th rib level and ham) compared to T1. Ham pH at 25min and at 20h post-mortem, and drip losses at 48h post-mortem were lower (P< 0.05) in T2 group vs. T1. Concerning the fatty acid profile, the T2 showed a greater concentration of C18:1 and C20:1 compared to T1. In conclusion, the addition of the sensorial additive at the end of the growing period changed carcass composition and quality traits under heat stress conditions
The Impact of Covid-19 Lockdown on Portuguese Households’ Food Waste Behaviors
Get PDFOn March 19, 2020, a State of Emergency was declared in Portugal as a way to contain the spread of the COVID-19. Restriction measures were adopted, limiting the mobility of the population. This paper presents preliminary results of an online survey to Portuguese households on the impact of COVID-19 lockdown on food purchase, storage, management, and waste generation. A total of 841 questionnaires were collected. The main changes observed were in food purchasing behavior, as 77 percent stated that they had reduced the frequency of grocery shopping, and 68 percent had bought more in local shops than before. Regarding food waste generation, the majority (60 percent), stated that during lockdown they threw away the same amount of food as before. 36 percent answered less than before, reporting that they had adopted strategies to reduce food waste. Vegetables, milk, and fruit were the goods with the highest reduction of food waste
Visible-NIR ‘point’ spectroscopy in postharvest fruit and vegetable assessment: The science behind three decades of commercial use
Get PDFThe application of visible (Vis; 400–750 nm) and near infrared red (NIR; 750–2500 nm) region spectroscopy to
assess fruit and vegetables is reviewed in context of ‘point’ spectroscopy, as opposed to multi- or hyperspectral
imaging. Vis spectroscopy targets colour assessment and pigment analysis, while NIR spectroscopy has been
applied to assessment of macro constituents (principally water) in fresh produce in commercial practice, and a
wide range of attributes in the scientific literature. This review focusses to key issues relevant to the widespread
implementation of Vis-NIR technology in the fruit sector. A background to the concepts and technology involved
in the use of Vis-NIR spectroscopy is provided and instrumentation for in-field and in-line applications, which
has been available for two and three decades, respectively, is described. A review of scientific effort is made for
the period 2015 - February 2020, in terms of the application areas, instrumentation, chemometric methods and
validation procedures, and this work is critiqued through comparison to techniques in commercial use, with
focus to wavelength region, optical geometry, experimental design, and validation procedures.
Recommendations for future research activity in this area are made, e.g., application development with consideration
of the distribution of the attribute of interest in the product and the matching of optically sampled and
reference method sampled volume; instrumentation comparisons with consideration of repeatability, optimum
optical geometry and wavelength range). Recommendations are also made for reporting requirements, viz.
description of the application, the reference method, the composition of calibration and test populations, chemometric
reporting and benchmarking to a known instrument/method, with the aim of maximising useful
conclusions from the extensive work being done around the world
Molecular Assisted Selection for Pollination-Constant and Non-Astringent Type without Male Flowers in Spanish Germplasm for Persimmon Breeding
Get PDFPersimmon (Diospyros kaki Thunb) species is a hexaploid genotype that has a morphologically
polygamous gyonodioecious sexual system. D. kaki bears unisexual flowers. The presence of male
flowers resulted in the presence of seeds in the varieties. The fruits of persimmon are classified
according to their astringency and the pollination events that produced seeds and modify the levels of
astringency in the fruit. The presence of seeds in astringent varieties as pollination variant astringent
(PVA), pollination variant non-astringent (PVNA) and pollination constant astringent (PCA) resulted
in fruits not marketable. Molecular markers that allow selection of the varieties according to the type
of flowers at the plantlet stage would allow selection of seedless varieties. In this study, a marker
developed in D. lotus by bulk segregant analysis (BSA) and amplified fragment length polymorphism
(AFLP) markers, named DlSx-AF4, has been validated in a germplasm collection of persimmon,
results obtained agree with the phenotype data. A second important trait in persimmon is the
presence of astringency in ripened fruits. Fruits non-astringent at the ripen stage named pollination
constant non-astringent (PCNA) are the objective of many breeding programs as they do not need
removal of the astringency by a postharvest treatment. Astringency in the hexaploid persimmon is a
dominant trait. The presence of at least one astringent allele confers astringency to the fruit. In this
paper we checked the marker developed linked to the AST gene. Our goal has been to validate both
markers in germplasm from different origins and to test the usefulness in a breeding program
A key ‘foxy’ aroma gene is regulated by homologyinduced promoter indels in the iconic juice grape ‘Concord’
Get PDF‘Concord’, the most well-known juice grape with a parentage of the North American grape species Vitis labrusca L., possesses a special ‘foxy’ aroma predominantly resulted from the accumulation of methyl anthranilate (MA) in berries. This aroma, however, is often perceived as an undesirable attribute by wine consumers and rarely noticeable in the common table and wine grape species V. vinifera. Here we discovered homology-induced promoter indels as a major genetic mechanism for species-specific regulation of a key ‘foxy’ aroma gene, anthraniloyl-CoA:methanol acyltransferase (AMAT), that is responsible for MA biosynthesis. We found the absence of a 426-bp and/or a 42-bp sequence in AMAT promoters highly associated with high levels of AMAT expression and MA accumulation in ‘Concord’ and other V. labrusca-derived grapes. These promoter variants, all with direct and inverted repeats, were further confirmed in more than 1,300 Vitis germplasm. Moreover, functional impact of these indels was validated in transgenic Arabidopsis. Superimposed on the promoter regulation, large structural changes including exonic insertion of a retrotransposon were present at the AMAT locus in some V. vinifera grapes. Elucidation of the AMAT genetic regulation advances our understanding of the ‘foxy’ aroma trait and makes it genetically trackable and amenable in grapevine breeding
Direct Measurement of Mass and Economic Harvest and Post-Harvest Losses in Spanish Persimmon Primary Production
Get PDFGlobally, one in every three produced kilograms is wasted at some point along the entire agri-food chain. Unfortunately, knowledge about losses and waste is not equally distributed along the food chain. In fact, in some stages the primary data required to properly estimate the magnitude of the problem are lacking. This is especially true for agricultural production, for which studies that have used on-site measurements are scarce. The present study analyses the mass losses and unpaid share that occur during the harvest process and persimmon storage in warehouses in the Valencia region, Spain. The study was carried out using on-site measurements and primary data from the harvest and storage phases. Losses were also classified according to their causes. The total mass and economic losses were estimated as either 29.5% for the total produced volume or 38.5% for the number of finally commercialised kilograms. This work aims to highlight the complex problem in primary production with the mass and economic losses that farmers bear and to show the potential of loss reduction measures
Riego de un cultivo de citricos con agua marina desalinizada. resultados preliminares en suelo y planta
Get PDFLa escasez de agua y la creciente presión sobre los recursos hídricos en las regiones
semiáridas ha extendido la utilización para el riego de recursos hídricos no convencionales,
como el agua marina desalinizada (AMD). Debido a su composición en Cl-, Na+ y B3+, el riego
con AMD podría causar problemas agronómicos y afectar al suelo y a los cultivos a medio y
largo plazo. En este estudio, se regó una parcela de mandarinos durante 20 meses con (i)
agua proporcionada por la Comunidad de Regantes del Campo de Cartagena (CR), (ii) agua
marina desalinizada (AMD) y (iii) mezcla de agua 50% CR y 50% AMD (AM). Se evaluó el
efecto sobre la dinámica y acumulación de los iones tóxicos Cl-, Na+ y B3+ en el suelo y en la
planta. La [B3+] del agua AMD fue superior a la de CR, acumulándose en el suelo, con una
concentración un 25% superior a la encontrada con CR al final del ensayo. La [B3+] en la capa
superficial del suelo se correlacionó con la [B3+] en el agua y con la [B3+] en la hoja. Aunque
tras 20 meses los árboles regados con AMD tuvieron una [B3+] foliar un 25% superior a la de
árboles regados con CR, no presentaron síntomas de toxicidad. Las [Cl-] y [Na+] del agua
fueron similares en los tres tipos de agua, superando los umbrales a partir de los cuales
pueden producir toxicidad en cítricos. Las concentraciones de Cl- y Na+ en hoja permanecieron
por debajo del umbral de toxicidad establecido para cítricos. Los resultados obtenidos son
preliminares ya que este estudio debería extenderse durante un periodo más largo para
obtener datos más concluyentes acerca de los efectos a largo plazo de la utilización de AMD
tanto en el suelo como en la planta
IPM-recommended insecticides harm beneficial insects through contaminated honeydew
Get PDFThe use of some systemic insecticides has been banned in Europe because they are toxic to beneficial insects when these feed on nectar. A recent study shows that systemic insecticides can also kill beneficial insects when they feed on honeydew. Honeydew is the sugar-rich excretion of hemipterans and is the most abundant carbohydrate source for beneficial insects such as pollinators and biological control agents in agroecosystems. Here, we investigated whether the toxicity of contaminated honeydew depends on i) the hemipteran species that excretes the honeydew; ii) the active ingredient, and iii) the beneficial insect that feeds on it. HPLC-MS/MS analyses demonstrated that the systemic insecticides pymetrozine and flonicamid, which are commonly used in Integrated Pest Management programs, were present in honeydew excreted by the mealybug Planococcus citri. However, only pymetrozine was detected in honeydew excreted by the whitefly Aleurothixus floccosus. Toxicological studies demonstrated that honeydew excreted by mealybugs feeding on trees treated either with flonicamid or pymetrozine increased the mortality of the hoverfly Sphaerophoria rueppellii, but did not affect the parasitic wasp Anagyrus vladimiri. Honeydew contaminated with flonicamid was more toxic for the hoverfly than that contaminated with pymetrozine. Collectively, our data demonstrate that systemic insecticides commonly used in IPM programs can contaminate honeydew and kill beneficial insects that feed on it, with their toxicity being dependent on the active ingredient and hemipteran species that excretes the honeydew
Analysis of Crossover Events and Allele Segregation Distortion in Interspecific Citrus Hybrids by Single Pollen Genotyping
Get PDFIn citrus, a classical method of studying crossovers and segregation distortion (SD) is the genetic analysis of progenies. A new strategy combining fluorescence-activated cell sorting and whole genome amplification of haploid pollen nuclei with a large set of molecular markers, offers the opportunity to efficiently determine the frequency of crossovers and the identification of SD without the need to generate segregating populations. Here we have analyzed meiotic crossover events in a pollen nuclei population from “Eureka” lemon and the allelic SD was evaluated in a pollen nuclei population from a clementine × sweet orange hybrid (“CSO”). Data obtained from the “CSO” pollen nuclei population were compared to those obtained from genotyping of a segregating population (“RTSO”) arising from a hand-made sexual hybridization between diploid non apomictic selected tangor (mandarin × sweet orange; “RTO” tangor) as female parent pollinated with “CSO” tangor as male parent. The analysis of crossovers rates on chromosome 1 revealed the presence of up to five crossovers events on one arm and four on the corresponding other arm, with an average of 1.97 crossovers per chromosome while no crossover events were observed in five “Eureka” lemon pollen nuclei. The rate of SD observed in “CSO” pollen nuclei (13.8%) was slightly lower than that recovered in the “RTSO” population (20.7%). In the pollen nuclei population, SD was found on linkage group (LG) 2, while the “RTSO” population showed SD on LGs 2 and 7. Potential male gametic selection mechanisms were distinguished in pollen grains, while in the population, mechanisms of gametophytic selection and/or zygotic selection were observed. This methodology is a very useful tool to facilitate research focused on the reproductive biology of citrus and study the mechanisms that affect crossovers and SD