BUSCADOR RECOLECTA

Introduction: cycling Dof transcription factors (CDFs) have been involved in different aspects of plant growth and development. In Arabidopsis and tomato, one member of this family (CDF1) has recently been associated with the regulation of primary metabolism and abiotic stress responses, but their roles in crop production under open field conditions remain unknown. Methods: in this study, we compared the growth, and tuber yield and composition of plants ectopically expressing the CDF1 gene from Arabidopsis under the control of the 35S promoter with wild-type (WT) potato plants cultured in growth chamber and open field conditions. Results: in growth chambers, the 35S::AtCDF1 plants showed a greater tuber yield than the WT by increasing the biomass partition for tuber development. Under field conditions, the ectopic expression of CDF1 also promoted the sink strength of the tubers, since 35S::AtCDF1 plants exhibited significant increases in tuber size and weight resulting in higher tuber yield. A metabolomic analysis revealed that tubers of 35S::AtCDF1 plants cultured under open field conditions accumulated higher levels of glucose, starch and amino acids than WT tubers. A comparative proteomic analysis of tubers of 35S::AtCDF1 and WT plants cultured under open field conditions revealed that these changes can be accounted for changes in the expression of proteins involved in energy production and different aspects of C and N metabolism. Discussion: The results from this study advance our collective understanding of the role of CDFs and are of great interest for the purposes of improving the yield and breeding of crop plants., This study was supported by the Ministerio de Ciencia e Innovación (MCIN) and the Agencia Estatal de Investigación (AEI) / 10.13039/501100011033/ (grants RTA2015-00014-c02-00 to JM and SGN; PID2020-114165RR-C21 to JM), (BIO2017-82873-R to JVC) (PID2019-104685GB-100 to JP-R, EB-F and FJM), the Gobierno de Navarra (PC036-037 BIOMEF to EB-F and FJM) and the Vicerrectorado de Investigación de la Universitat Politècnica de València (PAID-11-21 to SGN), J.C is funded by the National Agency for Research and Development (ANID) Chile with Program FONDECYT Regular 1190812 and ANID-Millennium Science Initiative Program-ICN17_022" and The GEP Chinese pre-doctoral fellowship to LY. We also want to acknowledge the "Severo Ochoa Program for Centres of Excellence in R&D" (CEX2020-000999-S) supported by MCIN/AEI/10.13039/501100011033 for supporting the scientific services used in this study.

[EN] High-quality crop production with minimal fertilizer inputs is a key goal for the agriculture of the future. Globally, tomato is one of the most important vegetable crops and its intensive production and breeding has been based on the application of large quantities of nitrogen (N) fertilizers. Therefore, the development of N use efficient (NUE) cultivars with low N inputs needs to be addressed. Some variability in plant growth, fruit quality and NUE traits among tomato ( Solanum lycopersicum L.) varieties under low N supply has been reported, however, the relevance of wild relatives of tomato has not yet been assessed. In this study, we found that S. pimpinellifolium accession To-937 (SP) may be a suitable resource to increase NUE in tomato. We studied a set of 29 introgression lines (IL) from SP into the Moneymaker cultivar (MM) in different seasons to investigate the potential of SP introgressions to maintain the tomato plant performance during the growth cycle under low N input in greenhouse conditions. We identified specific regions in the SP genome, on chromosomes 1, 3 and 10, involved in the responses to N inputs of fruit production and fruit quality. Notably, the line SP_10-4 maintained vegetative biomass and fruit yield production under limiting N supply. The introgressed region contained putative candidate genes as sucrose phosphate phosphatase ( SPP ), invertases (INV) and glutamine synthase 1 ( GS1 ) genes, implicated in C and N metabolism. Genomic and expression analyses revealed differences in coding and non-coding sequences as well as in mRNA levels in SP_10-4, suggesting that these genes might well contribute to the reported biomass responses to N. Additionally, line SP_1-4 showed stable fruit amino acid contents under both sufficient and limiting N supplies, indicating that assimilated N partitioning to the fruit is maintained in response to N. Altogether, our results confirmed the suitability of SP as a source of NUE related traits and the interest in the studied ILs for developing new tomato cultivars with improved NUE under sustainable fertilization conditions., This work was supported by the Ministerio de Ciencia e Innovacion (MCIN) and the Agencia Estatal de Investigacion (grants RTA2015-00014-c02-00 to SGN and JM, PID2020-114165RR-C21 to JM, and PID2022-136541OB-I00 to SGN), the Agroalnext program (MCIN with funding of NextGenEU-PRTR-C17.I1 Generalitat Valenciana AGROALNEXT/2022/056 to SGN), Vicerrectorado de Investigacion de la Universitat Politecnica de Valencia (PAID-11-21 to SGN; PAID-10-20 and PAID-PD-22 to RM), Ministerio de Ciencia e Innovacion (TED2021-129296B-I00 to SGN) and European Commission H2020 research and innovation program through HARNESSTOM grant agreement no. 101000716 (to AG) and RoxyCOST CA18210 for networking activities (to AG). We also want to acknowledge the "Severo Ochoa Program for Centers of Excellence in R&D" (CEX2020-000999-S) supported by MCIN/AEI/10.13039/501100011033. We thank Mike Bennett for revising the English language and Javier Forment from the IBMCP Bioinformatics service for support on genomic analyses.

[EN] Grafting in tomato ( Solanum lycopersicum L.) has mainly been used to prevent damage by soil-borne pathogens and the negative effects of abiotic stresses, although productivity and fruit quality can also be enhanced using high vigor rootstocks. In the context of a low nutrients input agriculture, the grafting of elite cultivars onto rootstocks displaying higher Nitrogen Use Efficiency (NUE) supports a direct strategy for yield maximization. In this study we assessed the use of plants overexpressing the Arabidopsis ( AtCDF3 ) or tomato ( SlCDF3 ) CDF3 genes, previously reported to increase NUE in tomato, as rootstocks to improve yield in the grafted scion under low N inputs. We found that the AtCDF3 gene induced greater production of sugars and amino acids, which allowed for greater biomass and fruit yield under both sufficient and limiting N supplies. Conversely, no positive impact was found with the SlCDF3 gene. Hormone analyses suggest that gibberellins (GA 4 ), auxin and cytokinins (tZ) might be involved in the AtCDF3 responses to N. The differential responses triggered by the two genes could be related, at least in part, to the mobility of the AtCDF3 transcript through the phloem to the shoot. Consistently, a higher expression of the target genes of the transcription factor, such as glutamine synthase 2 ( SlGS2 ) and GA oxidase 3 ( SlGA3ox ), involved in amino acid and gibberellin biosynthesis, respectively, was observed in the leaves of this graft combination. Altogether, our results provided further insights into the mode of action of CDF3 genes and their biotechnology potential for transgrafting approaches., This work was supported by the Ministerio de Ciencia e Innovacion (MCIN) and the Agencia Estatal de Investigacion (grants RTA2015-00014-c02-00 to SGN and JM, PID2020-114165RR-C21 to JM, and PID2022-136541OB-I00 to SGN). We also want to acknowledge the "Severo Ochoa Program for Centers of Excellence in R&D" (CEX2020-000999-S) supported by MCIN/AEI/10.13039/501100011033.

[EN] IntroductionCycling Dof transcription factors (CDFs) have been involved in different aspects of plant growth and development. In Arabidopsis and tomato, one member of this family (CDF1) has recently been associated with the regulation of primary metabolism and abiotic stress responses, but their roles in crop production under open field conditions remain unknown. MethodsIn this study, we compared the growth, and tuber yield and composition of plants ectopically expressing the CDF1 gene from Arabidopsis under the control of the 35S promoter with wild-type (WT) potato plants cultured in growth chamber and open field conditions. ResultsIn growth chambers, the 35S::AtCDF1 plants showed a greater tuber yield than the WT by increasing the biomass partition for tuber development. Under field conditions, the ectopic expression of CDF1 also promoted the sink strength of the tubers, since 35S::AtCDF1 plants exhibited significant increases in tuber size and weight resulting in higher tuber yield. A metabolomic analysis revealed that tubers of 35S::AtCDF1 plants cultured under open field conditions accumulated higher levels of glucose, starch and amino acids than WT tubers. A comparative proteomic analysis of tubers of 35S::AtCDF1 and WT plants cultured under open field conditions revealed that these changes can be accounted for changes in the expression of proteins involved in energy production and different aspects of C and N metabolism. DiscussionThe results from this study advance our collective understanding of the role of CDFs and are of great interest for the purposes of improving the yield and breeding of crop plants., We thank Manuel Sanchez-Perales and Antonio Ramos for his technical assistance and Mike Bennet for English edditing. This study was supported by the Ministerio de Ciencia e Innovacion (MCIN) and the Agencia Estatal de Investigacion (AEI)/10.13039/501100011033/(grants RTA2015-00014-c02-00 to JM and SGN; PID2020-114165RR-C21 to JM), (BIO2017-82873-R to JVC) (PID2019-104685GB-100 to JP-R, EB-F and FJM), the Gobierno de Navarra (PC036-037 BIOMEF to EB-F and FJM ) and the Vicerrectorado de Investigacion de la Universitat Politecnica de Valencia (PAID-11-21 to SGN), J.C is funded by the National Agency for Research and Development (ANID) Chile with Program FONDECYT Regular 1190812 and ANID-Millennium Science Initiative Program-ICN17_022"and The GEP Chinese pre-doctoral fellowship to LY. We also want to acknowledge the "Severo Ochoa Program for Centres of Excellence in R & D"(CEX2020-000999-S) supported by MCIN/AEI/10.13039/501100011033 for supporting the scientific services used in this study .