Drought tolerance memory transmission by citrus buds. (July 2022)

• Record Type: Journal Article
• Authors: de Oliveira Sousa, Andressa Rodrigues; Ribas, Rogério Ferreira; Filho, Mauricio Antônio Coelho; Freschi, Luciano; Ferreira, Claudia Fortes; Filho, Walter dos Santos Soares; Pérez-Molina, Junior Pastor; da Silva Gesteira, Abelmon
• Is Part Of: Plant science. Volume 320(2022)
• Publication Date: 2022-07
• Subjects: Abiotic stress -- Citrus -- Epigenetics -- Photosynthetic performance -- Water deficit; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2022.111292
• Languages: English
• ISSNs: 0168-9452

Abstract

Abstract: Plants face recurrent drought events, and previous stresses can influence their responses to subsequent stress episodes. Studies on drought stress memory are recent in citriculture, although they show promise as a tool for crop improvement. Here, we investigated whether stress memory mechanisms can be detected in citrus plants grafted with buds from plants subjected to recurrent water deficit. Three rootstock varieties, namely 'Rangpur Santa Cruz' lime, 'Sunki Maravilha' mandarin and 'Sunki Tropical' mandarin, in combination with 'Valencia' orange, were either maintained under full irrigation or subjected to one, two, or three water deficit cycles. Buds from 'Valencia' orange were grafted onto 'Swingle' citrumelo rootstocks and were evaluated. This combination displayed improved physiological and biochemical performance under water limitation, especially 'Valencia' buds grafted onto 'Sunki Maravilha', with better photosynthetic performance under water deficit. These findings indicate that genotype-dependent epigenetic memory is a key factor in restoring citrus plants' capacity to rely on previous stress experiences to restore better photosynthetic and physiological responses when undergoing new water deficit events. Therefore, epigenetic marks can be stored and transmitted to new citrus plants and are a promising alternative to enable increased water deficit tolerance when plants are then challenged by drought-prone environments. Highlights: Citrus rootstock and scion combinations display a "genotype-dependent memory" to water deficit conditions. `Sunki Maravilha´ rootstocks are more sensitive to epigenetic modulation to water deficit. This study is the first to evidence that epigenetic marks can be stored and transmitted to new citrus plants, favoring water deficit tolerance and citriculture management.