caa a22 4500 605480567 CHVBK 20210128100416.0 cr unu---uuuuu 210128e20150301xx s 000 0 eng 10.1007/s11099-015-0085-6 doi (NATIONALLICENCE)springer-10.1007/s11099-015-0085-6 The effect of irradiance and water restriction on photosynthesis in young jatobá-do-cerrado ( Hymenaea stigonocarpa ) plants [Elektronische Daten] [A. Costa, S. Rezende-Silva, C. Megguer, L. Moura, M. Rosa, A. Silva] High irradiance promotes decreases in the quantum yield in plants, which reduce the photosynthetic rate. The excess of light in combination with water deficit can intensify the response of plants to stress, especially in species susceptible to those factors. The aim of the present study was to characterize the photosynthetic activity of young jatobá-do-cerrado (Hymenaea stigonocarpa Mart. ex Hayne) trees under different irradiance conditions, both alone and/or in combination with water deficit. Four irradiances [45, 230, 510, and 1,700 μmol(photon) m−2 s−1] and two levels of water in soil (90% and 50% of field capacity) were used. Gas exchange, water potential, and chlorophyll a fluorescence were measured. The highest rates of photosynthesis were observed under irradiances of 230 and 510 μmol(photon) m−2 s−1. Irradiance of 1,700 μmol(photon) m−2 s−1 led to the photoinhibition of photosynthesis, as indicated by a reduced maximum quantum yield of PSII, effective quantum yield ratio, and electron transport rate, as well as higher nonphotochemical quenching. The most stressful to young H. stigonocarpa plants was high irradiance, while water deficit did not intensify the response to light stress. The Institute of Experimental Botany, 2015 Brazil savanna nationallicence luminosity nationallicence photoinhibition nationallicence water potential nationallicence C i/ C a : ratio of intercellular and ambient concentration of CO2 nationallicence Chl : chlorophyll nationallicence E : transpiration rate nationallicence ETR : electron transport rate nationallicence Fm : maximal fluorescence yield of the dark-adapted state nationallicence F0 : minimal fluorescence yield of the dark-adapted state nationallicence Fv : variable fluorescence nationallicence Fv/Fm : maximal quantum yield of PSII photochemistry nationallicence FC : field capacity nationallicence g s : stomatal conductance nationallicence LF : full sun [1,700 μmol(photon) m−2 s−1] nationallicence L45, L230, and L510 : irradiances of 45, 230, and 510 μmol(photon) m−2 s−1, respectively nationallicence P N : net photosynthetic rate nationallicence NPQ : nonphotochemical quenching nationallicence qP : photochemical quenching coefficient nationallicence VPD : vapor pressure deficient nationallicence ΔF/Fm′ : effective quantum yield of PSII photochemistry nationallicence Ψw : water potential nationallicence Costa A. Laboratório de Ecofisiologia e Produtividade Vegetal, Instituto Federal de Educação, Ciência e Tecnologia Goiano — Campus Rio Verde, Caixa Postal 66, 75901-970, Rio Verde, GO, Brazil aut Rezende-Silva S. Laboratório de Ecofisiologia e Produtividade Vegetal, Instituto Federal de Educação, Ciência e Tecnologia Goiano — Campus Rio Verde, Caixa Postal 66, 75901-970, Rio Verde, GO, Brazil aut Megguer C. Laboratório de Ecofisiologia e Produtividade Vegetal, Instituto Federal de Educação, Ciência e Tecnologia Goiano — Campus Rio Verde, Caixa Postal 66, 75901-970, Rio Verde, GO, Brazil aut Moura L. Laboratório de Ecofisiologia e Produtividade Vegetal, Instituto Federal de Educação, Ciência e Tecnologia Goiano — Campus Rio Verde, Caixa Postal 66, 75901-970, Rio Verde, GO, Brazil aut Rosa M. Laboratório de Ecofisiologia e Produtividade Vegetal, Instituto Federal de Educação, Ciência e Tecnologia Goiano — Campus Rio Verde, Caixa Postal 66, 75901-970, Rio Verde, GO, Brazil aut Silva A. Departamento de Biologia Vegetal, Ed. CCBII, Universidade Federal de Viçosa, Campus Universitário, Av. P. H. Rolfs s/n, 36570-900, Viçosa, MG, Brazil aut Photosynthetica The Institute of Experimental Biology of the Czech Academy of Sciences 53/1(2015-03-01), 118-127 0300-3604 53:1<118 2015 53 11099 https://doi.org/10.1007/s11099-015-0085-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11099-015-0085-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Costa A. Laboratório de Ecofisiologia e Produtividade Vegetal, Instituto Federal de Educação, Ciência e Tecnologia Goiano — Campus Rio Verde, Caixa Postal 66, 75901-970, Rio Verde, GO, Brazil aut NATIONALLICENCE 700 1- Rezende-Silva S. Laboratório de Ecofisiologia e Produtividade Vegetal, Instituto Federal de Educação, Ciência e Tecnologia Goiano — Campus Rio Verde, Caixa Postal 66, 75901-970, Rio Verde, GO, Brazil aut NATIONALLICENCE 700 1- Megguer C. Laboratório de Ecofisiologia e Produtividade Vegetal, Instituto Federal de Educação, Ciência e Tecnologia Goiano — Campus Rio Verde, Caixa Postal 66, 75901-970, Rio Verde, GO, Brazil aut NATIONALLICENCE 700 1- Moura L. Laboratório de Ecofisiologia e Produtividade Vegetal, Instituto Federal de Educação, Ciência e Tecnologia Goiano — Campus Rio Verde, Caixa Postal 66, 75901-970, Rio Verde, GO, Brazil aut NATIONALLICENCE 700 1- Rosa M. Laboratório de Ecofisiologia e Produtividade Vegetal, Instituto Federal de Educação, Ciência e Tecnologia Goiano — Campus Rio Verde, Caixa Postal 66, 75901-970, Rio Verde, GO, Brazil aut NATIONALLICENCE 700 1- Silva A. Departamento de Biologia Vegetal, Ed. CCBII, Universidade Federal de Viçosa, Campus Universitário, Av. P. H. Rolfs s/n, 36570-900, Viçosa, MG, Brazil aut NATIONALLICENCE 773 0- Photosynthetica The Institute of Experimental Biology of the Czech Academy of Sciences 53/1(2015-03-01), 118-127 0300-3604 53:1<118 2015 53 11099