Trabajo presentado en el 15th Congress of the Mediterranean Phytopathological Union (Plant health sistaining Mediterranean ecosystems), celebrado en Córdoba (España) del 20 al 23 de junio de 2017.Anthracnose, caused by Colletotrichum acutatum, is
responsible for significant yield losses in commercial
strawberry production worldwide. For this reason,
it is of interest to uncover the molecular basis underlying
this strawberry/pathogen interaction. Previously,
FaWRKY1 was identified as an important
element mediating defence responses.This research was supported by the Project P12-AGR-2174 (Junta de Andalucía, Spain).Peer reviewe

Amil-Ruiz, Francisco

Arjona Girona, Isabel

Caballero Repullo, J. L.

Garrido Gala, José

Higuera-Sobrino, José Javier

Lekhbou, Ayman

López Herrera, Carlos

Mercado Carmona, J. A.

Molina-Hidalgo, F. J.

Muñoz-Blanco, Juan

Pliego-Alfaro, Fernando

Molina-Hidalgo, Francisco J.

Digital.CSIC

Phytopathologia Mediterranea33215th Congress of the Mediterranean Phytopathological Union, June 20–23, 2017, Córdoba, SpainDevelopmental processes regulated by small RNAs during Arabidopsis-Root knot nematode in-teraction. F.E. DÍAZ-MANZANO1, J. CABRERA1, M. BARCALA1, R. OLMO1, A.C. SILVA1, M.F. ANDRÉS2, I. MARTÍNEZ1, V. RUIZ-FERRER1, C. FENOLL1, C. ESCOBAR1. 1Facultad de Ciencias Ambientales y Bio-química, Universidad de Castilla-La Mancha, Avenida de Carlos III, s/n, 45071, Toledo, Spain. 2Departamento Pro-tección Vegetal, Instituto Ciencias Agrarias-CSIC, Calle Serrano, 115, 28006, Madrid, Spain. E-mail: Fernando.Diaz@uclm.esRoot knot nematodes (Meloidogyne spp.) currently cause major agricultural losses. They infect plants in the root elongation zone and penetrate intracellular-ly into the vascular cylinders, inducing galls contain-ing nematode feeding cells, the giant cells (GCs). We studied the differential transcriptome of Arabidopsis GCs and galls after Meloidogyne spp. Infection, as compared to vascular cells, revealing high-repressed genes probably due to gene expression reprogram-ming during their differentiation. Sequencing of small RNAs (sRNAs) showed profiles consistent with a role of sRNAs in gene silencing. The 24 nt-sRNAs, known to be involved in epigenetic regulation, were highly induced in early formed galls (3 d post infec-tion), and together with differentially regulated miR-NAs could be mediating the large gene repression that occurs during early development of GCs/galls. We have studied the roles of miR390 and miR172, ac-cumulated in galls at early infection stages. Loss of function Arabidopsis lines for both miRNAs showed reduced numbers of galls after nematode infection. The two miRNAs participate in plant developmen-tal processes in different ways. TAS3 precursor is cleaved by miR390 triggering tasiRNAs biogenesis that inhibits ARF2-4, releasing repression of lateral root growth. In contrast, miR172 downregulates the AP2-like genes during flowering via a translational mechanism rather than by mRNA cleavage. We dis-cuss the putative molecular networks induced by plant-nematodes in this biotic interaction through miR172 and miR390.Role of the PTC1 protein phosphatase in stress re-sponse in Fusarium oxysporum f. sp. lycopersici. P.P. FERREIRA LEMOS and C. HERA. Departamento de Genética. Campus Universitario de Rabanales. Univer-sidad de Córdoba. 14071 Córdoba, Spain.Type 2c Ser/Thr phosphatases (PTCs) are a class of protein phosphatases, conserved in eukaryotes. The PP2C proteins are involved in the regulation of many cellular functional processes, addressed by their role on MAPK cascades. Seven putative PTC proteins have been identified in Fusarium oxysporum f. sp lyco-persici 4287, using the BLAST algorithm, with PTCs from Saccharomyces cerevisiae and Fusarium gramine-arum. The expression of these genes in different stress conditions and plant infection was evaluated by RT-qPCR. Upregulation of ptc1 was observed af-ter cell wall stress, osmotic stress and plant infection, while downregulation was detected after invasive growth. A mutant strain, ∆ptc1, was obtained by the split marker strategy. The ∆ptc1 strain was more sen-sitive to SDS (0.125%) and menadione (20 μg mL-1) than the wild type, indicating possible roles of PTC1 in, respectively, cell wall/membrane stress (MPK1 pathway) and oxidative stress (HOG1 pathway). In addition, the ∆ptc1 strain showed greater tolerance to LiCl (0.15M and 0.30M) on different media pH (5, 7 and 8.5) than wild type, suggesting a role of PTC1 in lithium efflux mediated by the Nha1 (Na+/K+/Li+/Rb+ antiporter). The phosphorylation level of HOG1, MPK1 and FMK1 proteins was evaluated by western-blot; the ∆ptc1 strain showed increased phosphorylation level of HOG1 compared to the wild type. These results suggest an important role of PTC1 on the HOG1 pathway of Fusarium oxysporum f. sp lycopersici.This research was supported by the Project BIO2016-78923-R (Ministerio de Economía y Competitividad, Spain). PPFL received a PhD fellowship supported by CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Ministério de Educação, Brasil).Transient silencing of the FaWRKY1 strawberry gene (Fragaria x ananassa) in fruit induces resistance to Colletotrichum acutatum infection. J.J. HIGUERA-SOBRINO1, F.J. MOLINA-HIDALGO1, I. ARJONA-GIRONA2, F. AMIL-RUIZ1, J. GARRIDO-GALA1, A. LEKHBOU1, J.A. MERCADO3, F. PLIEGO-ALFARO3, J. MUÑOZ-BLANCO1, C.J. LÓPEZ-HERRERA2, J.L. CABALLERO1. 1Departamento de Bioquímica y Biología Molecular, Edif. Severo Ochoa-C6, Planta Baja-Ala Norte. Campus de Rabanales s/n. Universidad de Córdoba-14071, Córdoba, Spain. 2Departamento de Protección de Cultivos, Instituto de Agricultura Sostenible, C.S.I.C. C/Alameda del Obispo s/n, Apartado 4084, Córdoba, Spain. 3Departa-333Vol. 56, No. 2, August, 201715th Congress of the Mediterranean Phytopathological Union, June 20–23, 2017, Córdoba, Spainmento de Biología Vegetal, Instituto de Hortofruticultura Subtropical y Mediterránea ‘‘La Mayora’’, IHSM-UMA-CSIC, Universidad Málaga-29071, Málaga, ES. E-mail: b92hisoj@uco.esAnthracnose, caused by Colletotrichum acutatum, is responsible for significant yield losses in commercial strawberry production worldwide. For this reason, it is of interest to uncover the molecular basis un-derlying this strawberry/pathogen interaction. Pre-viously, FaWRKY1 was identified as an important element mediating defence responses. This gene en-codes an AtWRKY75-like transcription factor (type IIc), which is upregulated in strawberry following C. acutatum infection. In this study, Agrobacterium-mediated transient transformation was used to both silence and overexpress the FaWRKY1 gene in fruit, with the aim to clarify its function in the strawberry defense mechanism. Analyses of FaWRKY1-RNAi strawberry fruits showed resistance to C. acutatum infection, 5 d after inoculation with this pathogen. Overexpression of this gene in strawberry fruit showed increased susceptibility to C. acutatum. Mo-lecular analysis is being carried out with these fruit samples to elucidate candidate genes transcription-ally regulated by FaWRKY1. Furthermore, in vitro DNA-binding assays have revealed a tentative con-sensus sequence [G/T][T/C]TGAC[T/C], contain-ing the core sequence TGAC (W box), as the likely target sequence for FaWRKY1 binding. These analy-ses will strengthen genome-wide promoter target site prediction for FaWRKY1.This research was supported by the Project P12-AGR-2174 (Junta de Andalucía, Spain).Evidence that the putative movement protein (MP2) of Broad bean wilt virus 1 is a pathogenic-ity determinant. C. CARPINO1,2, I. FERRIOL1, L. ELVIRA-GONZÁLEZ1, L. RUBIO1,3, E. PERI2, S. DAVINO2,4, L. GALIPIENSO1,3,4. 1Instituto Valenciano de Investigaciones Agrarias (IVIA), Ctra. CV-315, 46113 Moncada, Valencia, Spain. 2Department of Agricultural and Forestry Science, University of Palermo, Piazza Ma-rina 61, 90133 Palermo, Italy. 3Euro-Mediterranean In-stitute of Science and Technology (IEMEST), Vía Michele Miraglia 20, 90139 Palermo, Italy. 4Departamento de Biotecnología,  Escuela Técnica Superior de Ingeniería Agronómica y del Medio Natural, Universidad Politéc-nica de Valencia, Camino de Vera s/n, 46022-Valencia, Spain.Broad bean wilt virus 1 (BBWV-1, genus Fabavirus, family Secoviridae) infects crops of economic impor-tance, such as broad bean, pepper, tomato, spinach, and ornamental plants. The virus genome is consti-tuted by two molecules of positive single stranded RNA, each encoding a polyprotein which is further processed by proteolytic cleavage. RNA1 encodes the proteins involved in viral replication and expres-sion, while RNA2 encodes the movement protein (MP) and two coat proteins (LCP and SCP). RNA2 contains an alternative second start codon rendering a smaller putative movement protein, called MP2. To date, the BBWV-1 proteins related to pathogenicity are unknown. The roles of MP2 in symptom deter-mination, post-transcriptional gene silencing (PTGS) and elicitation of hypersensitive response (HR) were examined. Expression of MP2 in Nicotiana bentha-miana through Potato virus X (PVX) caused necrotic lesions, indicating that MP2 is a symptom deter-minant. Analysis of O2- accumulation and necrosis staining revealed that this protein elicited the cel-lular HR. Transient expression of MP2 in N. bentha-miana 16C, that constitutively expresses Green Fluo-rescent Protein (GFP), and a complementation assay with a vector based on Turnip crinkle virus sequence (TCV-sGFP) showed that this protein acts as a sup-pressor of PTGS.Chlorophyll degradation pathway is linked to sto-matal and photosynthetic dysfunctions observed in oats resistant to powdery mildew. G. MONTIL-LA-BASCÓN1, M. ROCA2, L.A.J. MUR3, PRATS E1. 1Department of Plant breeding, Institute for Sustainable Agriculture (IAS), Spanish National Research Council (CSIC), Alameda del Obispo s/n, P.O. Box 4084, 14004 Córdoba, Spain. 2Food Phytochemistry Department, In-stituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC), University Campus Pablo de Olavide, Building 46, Sevilla 41013, Spain. 3Institute of Biological, Environmental and Rural Sciences, University of Aber-ystwyth, UK.Cost of resistance is usually associated with the en-ergy and nutritional penalties linked to induction of defenses. Currently, a mechanistic understanding of the sources of these costs is lacking, other than vague 

Transient silencing of the FaWRKY1 strawberry gene (Fragaria x ananassa) in fruit induces resistance to Colletotrichum acutatum infection

Transient silencing of the FaWRKY1 strawberry gene (Fragaria x ananassa) in fruit induces resistance to Colletotrichum acutatum infection

Abstract

Similar works

Full text

Available Versions

Digital.CSIC