Amil-Ruiz F.,University of Cordoba, Spain |
Encinas-Villarejo S.,University of Cordoba, Spain |
Munoz-Blanco J.,University of Cordoba, Spain |
Caballero J.L.,University of Cordoba, Spain |
And 6 more authors.
Acta Horticulturae | Year: 2012
Strawberry (Fragaria × ananassa) yields are strongly affected by fungal diseases and pests, e.g., Colletotrichum spp., forcing the excessive use of chemical products (mostly environmental contaminants) to control them. Resistant cultivars are a priority of most strawberry breeding programs; however, little is known about the genetic basis for strawberry's resistance to pathogens, and completely resistant cultivars have not been reported. Although molecular markers of disease resistance in strawberry have been reported, the octoploid genetic structure of commercial strawberry makes it difficult to associate molecular markers with disease resistance genes. To gain insights into the genetic mechanisms of defense against Colletotrichum acutatum, the transcriptome of two strawberry cultivars ('Camarosa' and 'Andana') exhibiting different susceptibility to this pathogen has been analyzed. An in-house cDNA microarray based on a 3264 strawberry probe set was fabricated from a strawberry differential ESTs collection previously obtained in response to this pathogen. Transcriptional comparison of these two cultivars was performed before and after infection. The expression of 190 genes was significantly altered, of which, 94 and 50 genes, were exclusively alterated in cultivars 'Camarosa' and 'Andana', respectively. Over-expression and siRNA approaches are being used for functional analysis of candidate genes. Valuable information is being generated as a tool for effective control strategies to increase resistance in strawberry.
Borrego-Benjumea A.,IAS |
Melero-Vara J.M.,IAS |
Basallote-Ureba M.J.,IFAPA Las Torres Tomejil
Acta Horticulturae | Year: 2010
Soil mixture (sand:silt, 2:1, v:v) was artificially infested with Fusarium oxysporum f. sp. asparagi (Foa) and thereafter amended with either poultry manure (PM, 1 and 2%, w:w), the pellet of PM (PMP, 1 and 2%, w:w), or composted olive residues (COR, 3 and 6%, w:w). Thoroughly homogenised soil was used to fill 50 ml tubes which were incubated at 30 and 35°C in the dark for 15, 30 or 45 d. Thereafter, the remaining soil in the tubes was individually added to growth substrate in pots where seedlings of the susceptible asparagus 'Grande' were planted. Foa viability was reduced by >90% in PMP-1-2% and PM-2% amended soils incubated at 30°C for 45 d; similar results were obtained when soils amended with PM, PMP or COR, or non-amended, were incubated at 35°C for ≥30 d. Root rot severity (% affected tissues) was reduced to 35 and 22%, as compared to their control plants, respectively growing on the PM- and PMP-treated pots, which were incubated at 30°C for 45 d. Foa-infested soil amended with PMP-2% and incubated at 30°C for 30 or 45 d determined a 325% increase of fresh plant weight, as compared to the un-amended Foa-infested control, whereas increases of 58 and 32% were observed in plants growing in un-infested PM and COR-amended soils that were incubated at 35°C for 15 d. In general, 45-d incubation reduced inoculum viability and root severity and improved plant biomass, but these effects were larger at 35°C than at 30°C.
Sanchez-Canizares C.,Technical University of Madrid |
Rey L.,Technical University of Madrid |
Duran D.,Technical University of Madrid |
Temprano F.,IFAPA Las Torres Tomejil |
And 5 more authors.
Systematic and Applied Microbiology | Year: 2011
Lupinus mariae-josephi is a recently described endemic Lupinus species from a small area in Eastern Spain where it thrives in soils with active lime and high pH. The L. mariae-josephi root symbionts were shown to be very slow-growing bacteria with different phenotypic and symbiotic characteristics from those of Bradyrhizobium strains nodulating other Lupinus. Their phylogenetic status was examined by multilocus sequence analyses of four housekeeping genes (16S rRNA, glnII, recA, and atpD) and showed the existence of a distinct evolutionary lineage for L. mariae-josephi that also included Bradyrhizobium jicamae. Within this lineage, the tested isolates clustered in three different sub-groups that might correspond to novel sister Bradyrhizobium species. These core gene analyses consistently showed that all the endosymbiotic bacteria isolated from other Lupinus species of the Iberian Peninsula were related to strains of the B. canariense or B. japonicum lineages and were separate from the L. mariae-josephi isolates. Phylogenetic analysis based on nodC symbiotic gene sequences showed that L. mariae-josephi bacteria also constituted a new symbiotic lineage distant from those previously defined in the genus Bradyrhizobium. In contrast, the nodC genes of isolates from other Lupinus spp. from the Iberian Peninsula were again clearly related to the B. canariense and B. japonicum bv. genistearum lineages. Speciation of L. mariae-josephi bradyrhizobia may result from the colonization of a singular habitat by their unique legume host. © 2011 Elsevier GmbH.
Romero R.,Institute Recursos Naturales y Agrobiologia IRNASE CSIC |
Muriel J.L.,IFAPA Las Torres Tomejil |
Garcia I.,IFAPA Las Torres Tomejil |
Munoz de la Pena D.,University of Seville
Agricultural Water Management | Year: 2012
Availability of fresh water is one of the elementary conditions for life on Earth, however, water is a limited resource, which is now under an unprecedented pressure by global population growth, climate change and demand from several economic sectors such as tourism, industry, and agriculture. In particular, irrigated agriculture is one of the major water-consuming sectors. The aforementioned issues justify the need for a sustainable and rational use of water in irrigated crops, which motivates the implementation of new precise automatic irrigation technologies based on control theory. In this paper, we introduce the main concepts of control theory, how can it be applied to irrigation and a literature review of automatic irrigation control systems over the last decade. In addition, we present our latest developments in this field. In particular, we present some promising preliminary experimental results of four different control strategies applied to fruit trees in southern Spain to show the potential of the application of control techniques to irrigation. © 2012 Elsevier B.V.
Aguado A.,IFAPA Las Torres Tomejil |
Capote N.,IFAPA Las Torres Tomejil |
Romero F.,IFAPA Las Torres Tomejil |
Dodd I.C.,Lancaster University |
Colmenero-Flores J.M.,Institute Recursos Naturales y Agrobiologia IRNAS
Plant Science | Year: 2014
To investigate effects of soil moisture heterogeneity on plant physiology and gene expression in roots and leaves, three treatments were implemented in sunflower plants growing with roots split between two compartments: a control (C) treatment supplying 100% of plant evapotranspiration, and two treatments receiving 50% of plant evapotranspiration, either evenly distributed to both compartments (deficit irrigation - DI) or unevenly distributed to ensure distinct wet and dry compartments (partial rootzone drying - PRD). Plants receiving the same amount of water responded differently under the two irrigation systems. After 3 days, evapotranspiration was similar in C and DI, but 20% less in PRD, concomitant with decreased leaf water potential (Ψleaf) and increased leaf xylem ABA concentration. Six water-stress responsive genes were highly induced in roots growing in the drying soil compartment of PRD plants, and their expression was best correlated with local soil water content. On the other hand, foliar gene expression differed significantly from that of the root and correlated better with xylem ABA concentration and Ψleaf. While the PRD irrigation strategy triggered stronger physiological and molecular responses, suggesting a more intense and systemic stress reaction due to local dehydration of the dry compartment of PRD plants, the DI strategy resulted in similar water savings without strongly inducing these responses. Correlating physiological and molecular responses in PRD/DI plants may provide insights into the severity and location of water deficits and may enable a better understanding of long-distance signalling mechanisms. © 2014 Elsevier Ireland Ltd.