Maritime Pine Rootstock Genotype Modulates Gene Expression Associated with Stress Tolerance in Grafted Stems
Lorenzo Federico Manjarrez,
María Ángeles Guevara,
Nuria de María,
María Dolores Vélez,
Irene Cobo-Simón,
Miriam López-Hinojosa,
José Antonio Cabezas,
José Antonio Mancha,
Alberto Pizarro,
María Carmen Díaz-Sala,
María Teresa Cervera
Affiliations
Lorenzo Federico Manjarrez
Departamento de Ecología y Genética Forestal, Instituto de Ciencias Forestal (ICIFOR), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria—Consejo Superior de Investigaciones Científicas (INIA–CSIC), 28040 Madrid, Spain
María Ángeles Guevara
Departamento de Ecología y Genética Forestal, Instituto de Ciencias Forestal (ICIFOR), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria—Consejo Superior de Investigaciones Científicas (INIA–CSIC), 28040 Madrid, Spain
Nuria de María
Departamento de Ecología y Genética Forestal, Instituto de Ciencias Forestal (ICIFOR), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria—Consejo Superior de Investigaciones Científicas (INIA–CSIC), 28040 Madrid, Spain
María Dolores Vélez
Departamento de Ecología y Genética Forestal, Instituto de Ciencias Forestal (ICIFOR), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria—Consejo Superior de Investigaciones Científicas (INIA–CSIC), 28040 Madrid, Spain
Irene Cobo-Simón
Departamento de Ecología y Genética Forestal, Instituto de Ciencias Forestal (ICIFOR), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria—Consejo Superior de Investigaciones Científicas (INIA–CSIC), 28040 Madrid, Spain
Miriam López-Hinojosa
Departamento de Ecología y Genética Forestal, Instituto de Ciencias Forestal (ICIFOR), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria—Consejo Superior de Investigaciones Científicas (INIA–CSIC), 28040 Madrid, Spain
José Antonio Cabezas
Departamento de Ecología y Genética Forestal, Instituto de Ciencias Forestal (ICIFOR), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria—Consejo Superior de Investigaciones Científicas (INIA–CSIC), 28040 Madrid, Spain
José Antonio Mancha
Departamento de Ecología y Genética Forestal, Instituto de Ciencias Forestal (ICIFOR), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria—Consejo Superior de Investigaciones Científicas (INIA–CSIC), 28040 Madrid, Spain
Alberto Pizarro
Departamento de Ciencias de la Vida, Universidad de Alcalá (UAH), 28805 Alcalá de Henares, Spain
María Carmen Díaz-Sala
Departamento de Ciencias de la Vida, Universidad de Alcalá (UAH), 28805 Alcalá de Henares, Spain
María Teresa Cervera
Departamento de Ecología y Genética Forestal, Instituto de Ciencias Forestal (ICIFOR), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria—Consejo Superior de Investigaciones Científicas (INIA–CSIC), 28040 Madrid, Spain
Climate change-induced hazards, such as drought, threaten forest resilience, particularly in vulnerable regions such as the Mediterranean Basin. Maritime pine (Pinus pinaster Aiton), a model species in Western Europe, plays a crucial role in the Mediterranean forest due to its genetic diversity and ecological plasticity. This study characterizes transcriptional profiles of scion and rootstock stems of four P. pinaster graft combinations grown under well-watered conditions. Our grafting scheme combined drought-sensitive and drought-tolerant genotypes for scions (GAL1056: drought-sensitive scion; and Oria6: drought-tolerant scion) and rootstocks (R1S: drought-sensitive rootstock; and R18T: drought-tolerant rootstock). Transcriptomic analysis revealed expression patterns shaped by genotype provenance and graft combination. The accumulation of differentially expressed genes (DEGs) encoding proteins, involved in defense mechanisms and pathogen recognition, was higher in drought-sensitive scion stems and also increased when grafted onto drought-sensitive rootstocks. DEGs involved in drought tolerance mechanisms were identified in drought-tolerant genotypes as well as in drought-sensitive scions grafted onto drought-tolerant rootstocks, suggesting their establishment prior to drought. These mechanisms were associated with ABA metabolism and signaling. They were also involved in the activation of the ROS-scavenging pathways, which included the regulation of flavonoid and terpenoid metabolisms. Our results reveal DEGs potentially associated with the conifer response to drought and point out differences in drought tolerance strategies. These findings suggest genetic trade-offs between pine growth and defense, which could be relevant in selecting more drought-tolerant Pinus pinaster trees.
