03904nab a2200373 i 4500003000900000005001700009008004100026040001800067072001400085072001400099100002600113100002500139100003200164100002600196100002300222100002500245245011300270500006400383520127400447520129201721650001703013650001803030650002903048650001803077650001203095650001403107650001803121650001403139650002303153773024703176856008003423942000803503999001903511BR-BrBNA20250922182713.0250922b2021    bl.mr|pooa||| 00| 0 eng |  aBR-BrBNAbeng  aF60b1030  aF61b1050  aSilva, Tainá A. da   aBrito, Marcos E. B.   aConceição, Ivens H. da   aNunes, Ericlis D. S.   aSouza, Darvina S.   aMartins, Gabriel O.   aPhothochemical quenching is indicative of ionic stress on ‘Tahiti’ acid lime grafted on citrus genotypes  aPublicação on-line; 21 ref.; 4 illus; Sumaries (En, Pt)  a

ABSTRACT: The objective was to study the chlorophyll ‘a’ fluorescence and the photochemical quenching from ‘Tahiti’ acid lime grafted in new citrus genotypes under irrigation with three types of water during prefloration phase of the first year of cultivation, purposing to verify if the chlorophyll ‘a’ fluorescence and the photochemical quenching are indicatives of the beginning of ionic stress. An experiment was set up with three irrigation water salinity levels (0.14, 2.40 and 4.80 dS m-1), and 13 citrus rootstock, corresponding to ‘Rangpur Santa Cruz’ lime, three Citrandarins, the ‘Sunki Tropical’ mandarin and eight citrus hybrids, all grafted with the ‘Tahiti’ acid lime, using randomized block design with four replications. At 70 days after transplanting, the chlorophyll a fluorescence of the plants were evaluated. Photochemical quenching indicates begin of ionic saline stress in citrus plants; The ‘Tahiti’ acid lime grafted on TSKC x (LCR x TR) - 059, ‘Rangpur Santa Cruz’ lime, the Citrandarins ‘Riverside’ and ‘San Diego’ and TSKC x TRBK - 007 genotypes has greater activation of protective mechanisms through transient fluorescence.

Key words: Citrus spp., fluorescence, quantic efficiency, saline waters  a

RESUMO: Objetivou-se estudar fluorescência da clorofila ‘a’ e o quenching fotoquímico da limeira ácida ‘Tahiti’ enxertada em novos genótipos de citros sob irrigação com três tipos de água na fase de prefloração do primeiro ano de cultivo, no intuito de verificar se a fluorescência da clorofila ‘a’ e o quenching fotoquímico são indicativos do início do estresse iônico. No experimento, foram avaliados três condutividades elétricas da água de irrigação (0,14, 2,40 tangerineira ‘Sunki Tropical’ e oito híbridos de citros, todos enxertados com a limeira ácida ‘Tahiti’, no delineamento em blocos casualizados com quatro repetições. Foi avaliada, aos 70 dias após o transplante, a fluorescência da clorofila ‘a’. O quenching fotoquímico indica início do estresse iônico em plantas de citros sob irrigação com águas salinas; a limeira ácida ‘Tahiti’ enxertada nos genótipos TSKC x (LCR x TR) - 059, limoeiro ‘Cravo Santa Cruz’, Citrandarin ‘Riverside’, Citrandarin ‘San Diego’ e TSKC x TRBK - 007 têm maior ativação de mecanismos de proteção por meio da fluorescência transiente.

Palavras-chave: Citrus spp., fluorescência, eficiência quântica, águas salinas  aCITRICULTURA  aIRRIGAÇÃO  aCONDUTIVIDADE ELÉTRICA  aÁGUA SALINA  aLIMÃO  aTANGERINA  aPORTA-ENXERTO  aCLOROFILA  aFISIOLOGIA VEGETAL0 035349317810dCampina Grande-PB Universidade Federal de Campina Grande. Centro de Ciências e Tecnologia 1997o2024-4529tRevista Brasileira de Engenharia Agrícola e Ambiental (Brazil)x1415-4366gv. 25 (6) p. 409-414; (2021)wBR2025003682  uhttps://www.scielo.br/j/rbeaa/a/Dmc7kxb4vvy6fXVY7vD865b/?format=pdf&lang=en  cANA  c338309d338309