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New molecular methods for identification of Broad bean wilt virus 1
No full textBroad bean wilt virus 1 (BBWV-1) causes damages in economically important plant crops such as pepper, bean, spinach, etc. Fast, cheap and reliable diagnostic tools are crucial to limit or control the disease. In this work, tissue blot immunoassay (TBIA), dot-blot (DB) and tissue-print (TP)-hybridization were developed for BBWV-1 diagnosis and evaluated for sensitivity, specificity and reliability in plants of several host species grown in the greenhouse or in the field, in comparison with ELISA and RT-PCR. RT-PCR followed by DB-hybridization provided the most sensitive and efficient diagnostic, but the virus was also detected in most samples by ELISA. Detection by TBIA or by TP-hybridization avoided sample processing, but they were less consistent and greatly depended on host species and tissue. DB-hybridization with probes corresponding to different genomic regions allowed universal detection of BBWV-1 and discrimination between genetically distant isolates
Determinación de zonas susceptibles para el aprovechamiento energético de las deyecciones ganaderas en la Comunidad Valenciana
Get PDFLa producción ganadera de la Comunidad Valenciana se caracteriza por una elevada
industrialización, con explotaciones independientes del factor tierra. Por otro lado, los nuevos retos
impuestos por la legislación europea y la importancia socioeconómica del sector ganadero, exigen
medidas para su preservación, y que paralelamente garanticen un desarrollo sostenible y minimicen el
problema estructural de las deyecciones. No obstante, la problemática no es homogénea
geográficamente, presentándose tanto situaciones con exceso de estiércoles, como de deficiencia de
materia orgánica en el suelo en regiones de marcada vocación agrícola. De este modo, la valorización
energética de estas deyecciones en las zonas excedentarias, se presenta como una solución viable. En
este contexto, dentro del Plan Estratégico de la Ganadería Valenciana, se sitúa el Plan Integral de
Residuos Ganaderos, con el que se pretende gestionar de manera sostenible, ambiental y
económicamente, el problema de las deyecciones ganaderas. En el marco de este plan, se han
realizado dos estudios sobre la localización de la ganadería y la producción de deyecciones ganaderas
en la Comunidad Valenciana, presentándose como pasos previos a la toma de decisiones con objeto
de solucionar los problemas de la ganadería valenciana en materia de gestión de deyecciones. Así, en
el presente trabajo, partiendo de estos estudios, a través del empleo de sistemas de información
geográficos, se han tratado de identificar aquellas zonas en las que la instalación de plantas de
valorización de deyecciones en forma de biogás sea factible, considerando criterios tanto
agronómicos como logísticos con el fin de abordar la cuestión desde la viabilidad ambiental y
económica
Efecto de la fertirrigación fosforada en el crecimiento y absorción de nutrientes de la coliflor
Get PDFEn un ensayo de fertirrigación fosforada realizado en las parcelas experimentales de
la Fundación Ruralcaja, en Paiporta (Valencia), con diferentes dosis de fósforo (0, 50, 100
y 150 kg P2O5/ha) para evaluar su efecto sobre diferentes cultivos hortícolas, se ha
estudiado cuantitativamente el ritmo de crecimiento y absorción de macronutrientes (N,
P, K, Ca y Mg) en la coliflor (Brassica oleracea var. Botrytis) cv. Daydream de ciclo largo,
con una densidad de 2 plantas/m2. Durante el ciclo de cultivo se realizaron muestreos
de plantas cada 3 semanas para determinar la materia seca y el contenido de macronutrientes
en los diferentes órganos vegetativos de la planta (raíces, tallos, hojas y pellas) en dos
de los tratamientos: el testigo (P0) y la dosis intermedia de abonado (P2). También se
determinó la producción de biomasa y la absorción de nutrientes al final del ciclo de
cultivo en todos los tratamientos de abonado fosforado
Ensayo de cultivares de haba Muchamiel en agricultura ecológica
Get PDFEl haba (Vicia faba var. major) es un cultivo tradicional muy arraigado en las
huertas alicantinas, siendo su destino principal la producción para el mercado de
consumo en fresco y una de las fuentes de abono orgánico. El cultivar predominante
es el tipo “Muchamiel” en sus diversas variantes.
El material vegetal que se suele emplear procede mayoritariamente de
selecciones hechas por los propios agricultores. El objetivo principal del ensayo fue
comparar dichas selecciones con los cultivares comerciales “tipo Muchamiel” de las
casas de semillas. Con ello pretendíamos comprobar el comportamiento en cultivo
ecológico del material vegetal disponible en la actualidad
Parasitism of Spalangia cameroni (Hymenoptera, Pteromalidae), an idiobiont parasitoid on pupae of Ceratitis capitata (Diptera, Tephritidae)
Get PDFSpalangia cameroni Perkins, 1910 is a pteromalid hymenopteran, well known as a pupal parasitoid of flies belonging to different taxonomic families in the order Diptera, as Muscidae, Sarcophagidae and Anthomyiidae. This species is being used as a biological control agent against the housefly (Musca domestica) and the stable fly (Stomoxys calcitrans). In the family Tephritidae it was
known as a parasitoid of Anastrepha suspensa, Dacus cucurbitae and D. passiflorae, but recently it has been described as a parasitoid of the Mediterranean Fruit Fly, Ceratitis capitata, in the Valencian Community (Spain). Due to the importance of that fruit fly species as a serious pest on citrus and fruit trees, it has been started the rearing and the biological study of S. cameroni in laboratory conditions, in order to know its ability to be used in the biological control of the medfly. Biological and parasitic
parameters of the insect, as adult longevity, female fecundity and fertility, influence of host age and temperature on parasitism and female ability in searching the host buried in the ground, are being analysed
Parasitoids from Azores (Hymenoptera : Encyrtidae, Pteromalidae, Braconidae): potential use in integrated pest management against Ceratitis capitata (Diptera : Tephritidae)
No full textTwo hymenopterous parasitoids, Halticoptera patellana and Toxeumorpha nigricola, were recovered from Mediterranean fruit fly pupae on Sao Miguel Island, Azores. Both are new records for the Azores, and as Medfly parasitoids. Field-collected Tachinaephagus zealandicus was maintained on Medfly for 10 generations, but if it has potential as a biocontrol agent remains an open question
Effect of recombinant human follicle-stimulating hormone and luteinizing hormone on in vitro maturation of porcine oocytes evaluated by the subsequent in vitro development of embryos obtained by in vitro fertilization, intracytoplasmic sperm injection, or parthenogenetic activation
No full textThe aim of this work was to study the effect of recombinant human ( rh) FSH and LH on in vitro maturation of pig oocytes compared with a conventional hormonal supplement based on equine ( PMSG) and human chorionic gonadotropins ( hCG), as evaluated by the developmental ability of 3 types of pig embryos obtained by in vitro fertilization ( IVF), intracytoplasmic sperm injection ( ICSI), or artificial activation ( ATA). In Exp. 1, one cumulus-oocyte complex group ( A group) was supplemented with rh-FSH and rh-LH ( 0.1 IU/mL each), and the other group ( B group) was supplemented with PMSG and hCG ( 10 IU/mL each). No differences in nuclear maturation between the A and B groups were observed ( 68.5 vs. 71.4%, respectively). No differences were detected between hormonal treatments in the rates of cleavage or blastocyst formation of ATA, IVF, and ICSI embryos. Total cell number of the embryos was not significantly different in any experimental group ( A: 31.1, 28.5, and 19.8 vs. B: 25.2, 25.5, and 20.6 for ATA, IVF, and ICSI embryos, respectively). In Exp. 2, the effects of different concentrations of rh-FSH and rh-LH ( 0.5, 0.1, or 0.05 IU/mL) in maturation medium on nuclear maturation and in vitro development of embryos obtained by IVF were studied. No effect of different hormonal concentrations on blastocyst formation rates was observed ( 8.5, 13.0, and 5.7%, respectively). Blastocyst cell number was not different in any experimental group. In conclusion, the results obtained here permit us to substitute PMSG and hCG with rh-FSH and rh-LH and to produce pig embryos obtained by IVF, ICSI, or ATA
ACTA HORTICULTURAE
No full textIn any plant genetic transformation system, the use of a selectable marker gene is essential to promote the recovery of only transgenic plants. However, the presence of marker genes conferring antibiotic resistance in plants represents a serious obstacle for public acceptance and future commercialization. In citrus, selection using the selectable marker gene nptII, that confers resistance to the antibiotic kanamycin, is in general very effective. Search of alternatives to nptII selection is not easy. An attractive possibility is offered by the MAT (Multi-Auto-Transformation) system, which combines the ipt gene for positive selection with the recombinase system R/RS for removal of marker genes from transgenic cells after transformation. Transgenic shoots for ipt gene lose apical dominance and show a characteristic phenotype. We are testing the efficiency of positive selection and excision by recombination with a MAT vector that comprises the ipt gene as selectable marker and the recombinase R gene, in citrus. Transformation with the MAT vector has been attempted in two citrus genotypes, Pineapple sweet orange (Citrus sinensis L. Osb.) and Carrizo citrange (C. sinensis L. Osb. X Poncirus trifoliata L. Raf.). Results indicated that the IPT phenotype was clearly shown in sweet orange but not in citrange, and that excision was not always efficient and precise. Nevertheless, the easy visual detection of the IPT phenotype combined with the higher transformation efficiency achieved in sweet orange using this system open interesting perspectives for the generation of marker-free transgenic citrus plants
Life history of Eretmocerus mundus, a parasitoid of Bemisia tabaci, on tomato and sweet pepper
No full textEretmocerus mundus is native to the Mediterranean region where it is often observed to enter greenhouses to parasitize B. tabaci on fruiting vegetables and other host crops. Fecundity on tomato and pepper was evaluated by placing newly emerged pairs (n = 15) of E. mundus on leaf discs infested with second instar B. tabaci, the preferred stage, maintained at 25°C and changed daily until death of the female. All whitefly nymphs were observed for host feeding and inverted to count parasitoid eggs. Adult longevity was estimated at 7.3±0.8 d on tomato and 10.1±1.0 d on sweet pepper. Fecundity (number of hosts parasitized) was estimated 147.8±12.6 per female on tomato and 171.1±21.5 on pepper. Incidence of host feeding (number of hosts killed) was significantly greater on sweet pepper than on tomato, 15.6±1.9 vs. 10.4±1.3 nymphs per female, respectively. No significant differences were detected in the duration of life stages between sweet pepper and tomato. Preimaginal survivorship in clip cages was estimated at 69.5±11.9% on tomato and 76.6±10.5% on sweet pepper, with no statistical differences. Net reproductive rate (R o) was estimated at 63.8±8.2 and 51.0±4.4 on tomato and sweet pepper respectively. Generation time (T) was significantly greater on sweet pepper (19.3±0.5) than on tomato (17.9±0.4), but the estimate of intrinsic rate of increase (r m) was not statistically different at 0.216±0.005 and 0.219±0.004 respectively. These values are well above those reported for B. tabaci on any crop, indicating the potential of E. mundus to control this pest on solanaceous crops in the greenhouse. © 2006 IOBC
Genotypic characterization of Staphylococcus aureus strains isolated from rabbit lesions
No full textSince staphylococcal infections are the main pathological problem in rabbit does, the objective of this study was to characterize epidemiologically Staphylococcus aureus isolates from different lesion types in rabbits. Using 3 genetic markers (coagulase, staphylococcal protein A and clumping factor B genes), 22 different genotypes were identified among 301 isolates recovered from 259 rabbit does with 10 different kinds of chronic purulent lesions. These infected rabbits were obtained from 30 herds located in the Valencia province on the Spanish Mediterranean coast. The most frequent genotype was designated A1/II1/delta (coa/spa/clfB combination genotype) and represented 70.76% of the isolates. Although most genotypes were previously identified in other countries, novel types were also documented. No specificity between genotypes and nature of the pathologic process could be identified. After genetic comparison between strains from different origins, the results may suggest that rabbit, bovine and human S. aureus isolates are not clonally related, suggesting that specific host-dependent pathogenic factors may have evolved independently in these species. These differences indicate that a rational and effective strategy to control infections caused by rabbit-specific isolates may be advantageous. (c) 2006 Elsevier B.V. All rights reserved