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Moncada, Spain

Owens R.A.,U.S. Department of Agriculture | Sano T.,Hirosaki University | Duran-Vila N.,IVIA
Methods in Molecular Biology | Year: 2012

When Diener discovered Potato spindle tuber viroid in 1971 (Diener, Virology 45:411-428, 1971), only a limited number of techniques were available for plant virus detection and purification. Biological assays using indicator hosts showing characteristic symptoms of infection and able to support high levels of viroid replication played a critical role in viroid detection and characterization. Polyacrylamide gel electrophoresis (PAGE) was the first molecular technique to be used for the rapid (2-3 days) identification of viroid-infected plants. Because it is the only diagnostic method that is sequence-independent, PAGE under denaturing conditions continues to play a key role in the identification of new viroids. Starting in the early 1980s, dot blot hybridization began to replace PAGE for routine viroid diagnosis. The first diagnostic protocols based on reverse transcription-polymerase chain reaction (RT-PCR) appeared approximately 10 years later, and much effort has subsequently been devoted to simplifying the sample preparation procedure and identifying group-specific primer pairs. This chapter describes four simple, easy-to-follow protocols-two involving PAGE and two others based on enzymatic amplification of viroid cDNAs-that currently play key roles in viroid discovery and characterization. © 2012 Springer Science+Business Media, LLC. Source

Cebolla V.,IVIA | Llobell D.,VALSUR | Oliver A.,SURINVER | Valero L.M.,SURINVER | And 2 more authors.
Acta Horticulturae | Year: 2010

Dimethyl disulfide (DMDS) is an important compound of Allium spp., especially of garlic. Although its fumigant effects are recently discovered, DMDS has been used by petrochemical industry and even as aroma agent because of its strong smell to garlic. DMDS is a wide spectrum fumigant with nematicidal, fungicidal, insecticidal and herbicidal effects. We have studied its effects as an alternative to Methyl bromide in a set of experiments since the year 2003 to 2008. DMDS stand alone or mixed with chloropicrin at 50 or 25% were applied, as emulsifiable formulations, through the drip irrigation system and were also compared to the mixtures of 1,3-dichloropropene + chloropicrin. Experimental plots were established in two locations of Valencian Country (Spain). After disinfestations, a pepper crop was established to monitor agronomic behavior. 2 DMDS stand alone, at high rates (107 g/m2), have a remarkable herbicidal capacity; at lesser dosage, its mixtures with chloropicrin own an excellent fumigant effect that is improved when applied under VIF sheet. The fungicidal effect is also improved by the mixture. Once the application technique was debugged The fruit quality as well as the yield is alike to those obtained with the classical methyl bromide soil disinfestation technique and the mixtures of 1,3-dicholopropene and chloropicrin. Source

Baixauli C.,Fundacion Ruralcaja Valencia | Giner A.,Fundacion Ruralcaja Valencia | Najera I.,Fundacion Ruralcaja Valencia | Miguel A.,IVIA | And 4 more authors.
Acta Horticulturae | Year: 2012

The most interesting artichoke production period in the Spanish Mediterranean Coast is autumn-winter. Seeds of seven cultivars ('Imperial Star', 'Alberca', 'Harmony', 'Concerto', 'Madrigal', 'Opal' and 'Lorca') and five lines ('DS-1000', 'DS-2000', 'AR-1', 'AR-2' and 'AR-3') were sown in polystyrene trays on the 14th June 2005 and planted on the 1st August in south Valencia, Spain. 'Blanca de Tudela' and 'Violeta de Provenza', which are asexually propagated cultivars, were planted in the same date and used as controls. Three replicates of 10 plants per cultivar/line were arranged in a completely randomized design. All cultivars and lines were sprayed three times between 20th September and 20th October 2005 with gibberellic acid at 30 mg L-1. Harvest started in October for 'Blanca de Tudela' and among seed propagated cultivars/lines, 'Imperial Star' and 'Lorca' (beginning harvest in November) were the earliest, while 'Concerto' and 'Madrigal' (beginning harvest in February) were the latest. At the end of February 2006, 'Imperial Star' (0.72 kg m-2 of market yield), 'Blanca de Tudela', 'Lorca' and 'DS-1000' (0.66 kg m-2 for all three), were the most productive varieties. The highest total market yields (until the end of May 2006) were obtained in 'Madrigal' (2.28 kg m-2), 'Concerto' (1.86 kg m-2), 'AR-3' (1.77 kg m-2) and 'DS-1000' (1.69 kg m-2). Whereas the highest non-marketable yields were reached by 'AR-2' (1.05 kg m-2), 'AR-3' (0.84 kg m-2) and 'DS-2000' (0.78 kg m-2). Furthermore at the end of the experiment (end of May), there were not differences among cultivars/lines, for the variable head size (between 91 and 157 g), however some statistically differences during some controls made over the productive cycle were detected for this parameter. © ISHS. Source

Davino S.,University of Palermo | Willemsen A.,Polytechnic University of Valencia | Panno S.,University of Palermo | Davino M.,University of Catania | And 3 more authors.
PLoS ONE | Year: 2013

Citrus tristeza virus (CTV) outbreaks were detected in Sicily island, Italy for the first time in 2002. To gain insight into the evolutionary forces driving the emergence and phylogeography of these CTV populations, we determined and analyzed the nucleotide sequences of the p20 gene from 108 CTV isolates collected from 2002 to 2009. Bayesian phylogenetic analysis revealed that mild and severe CTV isolates belonging to five different clades (lineages) were introduced in Sicily in 2002. Phylogeographic analysis showed that four lineages co-circulated in the main citrus growing area located in Eastern Sicily. However, only one lineage (composed of mild isolates) spread to distant areas of Sicily and was detected after 2007. No correlation was found between genetic variation and citrus host, indicating that citrus cultivars did not exert differential selective pressures on the virus. The genetic variation of CTV was not structured according to geographical location or sampling time, likely due to the multiple introduction events and a complex migration pattern with intense co- and re-circulation of different lineages in the same area. The phylogenetic structure, statistical tests of neutrality and comparison of synonymous and nonsynonymous substitution rates suggest that weak negative selection and genetic drift following a rapid expansion may be the main causes of the CTV variability observed today in Sicily. Nonetheless, three adjacent amino acids at the p20 N-terminal region were found to be under positive selection, likely resulting from adaptation events. © 2013 Davino et al. Source

Asins M.J.,IVIA | Raga V.,IVIA | Roca D.,IVIA | Belver A.,CSIC - Experimental Station of El Zaidin | Carbonell E.A.,IVIA
Theoretical and Applied Genetics | Year: 2015

Key message: Rootstock HKT1 genotype affected fruit [Na+] and non-commercial fruit yield; QTL analysis of rootstock-mediated scion nutrition is a powerful forward genetic approach to identify wild genes for rootstock breeding.Abstract: The present study approaches the QTL dissection of rootstock effects on a commercial hybrid variety grafted on a population of RILs derived from Solanum pimpinellifolium, genotyped for 4370 segregating SNPs from the SolCAP tomato panel and grown under moderate salinity. Results are compared to those previously obtained under high salinity. The most likely functional candidate genes controlling the scion [Na+] were rootstock HKT1;1 and HKT1;2 as it was previously reported for non-grafted genotypes. The higher fruit [Na+] found when rootstock genotype was homozygote for SpHKT1 supports the thesis that scion HKT1 is loading Na+ into the phloem sap in leaves and unloading it in sink organs. A significant increment of small, mostly seedless, fruits was found associated with SlHKT1 homozygous rootstocks. Just grafting increased the incidence of blossom end rot and delayed fruit maturation but there were rootstock RILs that increased commercial fruit yield under moderate salinity. The heritability and number of QTLs involved were lower and different than those found under high salinity. Four large contributing (>17 %) rootstock QTLs, controlling the leaf concentrations of B, K, Mg and Mo were detected whose 2 Mbp physical intervals contained B, K, Mg and Mo transporter-coding genes, respectively. Since a minimum of 3 QTLs (two of them coincident with leaf K and Ca QTLs) were also found governing rootstock-mediated soluble-solids content of the fruit under moderate salinity, grafting desirable crop varieties on stress-tolerant rootstocks tenders an opportunity to increase both salt tolerance and quality. © 2015, Springer-Verlag Berlin Heidelberg. Source

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