Identification of a walnut (Juglans regia L.) germplasm collection and evaluation of their genetic variability by microsatellite markers [Identificación de cultivares de nogal (juglans regia L.) y evaluación de su variabilidad genética mediante marcadores microsatélites]
Lopez-Ortega G.,Instituto Murciano Of Investigacion |
Tomas D.F.,Instituto Murciano Of Investigacion
Spanish Journal of Agricultural Research | Year: 2011
The characterization and evaluation of walnut (Juglans regia) germplasm constitute important aspects of taxonomic analysis and are valuable tools for breeding programs. In this work, a collection of 57 common walnut cultivars, mainly coming from Spain and the USA, has been studied with microsatellite markers. To carry out this work, 32 primer pairs flanking simple sequence repeats previously developed in Juglans nigra were screened to select the loci that presented high polymorphism and that were easier to score. The 19 selected microsatellite markers allowed the discrimination of the studied cultivars, with a total of 97 alleles detected and an average of 5 alleles per locus, confirming that these markers are more suitable tools for walnut identification than other molecular markers studied previously. The genetic similarity estimated from the molecular data clearly separated the Spanish walnuts from the Californian genotypes. Allelic data are presented for use as size standards to assist in correcting laboratory-to laboratory variation of allele size calling. Some of them are compared with previous results published and the discrepancies found are discussed.
Romero P.,Instituto Murciano Of Investigacion |
Fernandez-Fernandez J.I.,Estacion Enologica |
Martinez-Cutillas A.,Instituto Murciano Of Investigacion
American Journal of Enology and Viticulture | Year: 2010
The effects of two regulated deficit-irrigation (RDI) strategies pre- and postveraison on soil-plant water relations and their influence on leaf area development, cluster microclimate, yield, and berry quality were evaluated during two years in field-grown Monastrell grapevines under semiarid conditions in southeastern Spain. Three treatments were applied. The control was irrigated at 60% ETc (crop evapotranspiration), or 319 mm water over the full season. Regulated deficit-irrigation treatment 1 (RDI-1) received the same irrigation as the control before fruit set, 30% ETc from fruit set to harvest, and 45% ETc postharvest. Regulated deficit-irrigation treatment 2 (RDI-2) was the same as RDI-1, but with 15% ETc from fruit set to harvest. RDI-1 maintained soil water content and vine water status adequate for sustaining leaf gas exchange, without affecting sugar accumulation or increasing polyphenols at harvest. Moreover, RDI-1 reduced yield and berry size and improved cluster microclimate by reducing leaf area and increased water use efficiency. However, RDI-2 suffered more stress, mainly postveraison. This severe water stress substantially reduced root-vine hydraulic conductance and leaf gas exchange, decreasing gas exchange efficiency, leaf nitrogen, and chlorophyll content. Excessive postveraison water stress advanced leaf abscission, reducing leaf area development and yield. Lower leaf photosynthesis and higher leaf abscission significantly decreased yield and sugar in RDI-2 berries compared with RDI-1. Polyphenol and anthocyanin content also decreased significantly in RDI-2 compared with RDI-1. To avoid severe root and leaf function damage and increase polyphenols in this cultivar, we identified optimum physiological thresholds for several vine water indicators pre- and postveraison. © 2010 by the American Society for Enology and Viticulture. © 2010.
Ruiz-Garcia Y.,University of Murcia |
Lopez-Roca J.M.,University of Murcia |
Bautista-Ortin A.B.,University of Murcia |
Gil-Munoz R.,Instituto Murciano Of Investigacion |
Gomez-Plaza E.,University of Murcia
American Journal of Enology and Viticulture | Year: 2014
One effect of applying elicitors to plants is an increase in phenolic and volatile compound content. In this study, grapes treated at veraison with a combination of benzothiadiazole (BTH) and methyl jasmonate (MeJA) were vinified and the volatile composition of the resulting wines was analyzed. Results indicate that the combined application of BTH and MeJA to the grapes led to wines with a similar composition in higher alcohols and esters as wines made with untreated grapes. Treated grapes led to wines with a significantly higher concentration of terpenes, with some of the terpenes only detected in wines from treated grapes. A descriptive sensory analysis indicated that these differences in volatile composition could be detected in wines, with wines made from treated grapes having significantly greater fruity notes, aroma, and mouthfeel quality. © 2014 by the American Society for Enology and Viticulture. All rights reserved.