The aim of this study was to determine which anthocyanins are related to the purple coloration of... more The aim of this study was to determine which anthocyanins are related to the purple coloration of young leaves in Coffea arabica var. Purpurascens and assess their impact on photosynthesis as compared to C. arabica var. Catuaí, with green leaves. Two delphinidin glicosides were identified and histological cross-sections showed they were located throughout the adaxial epidermis in young leaves, disappearing as the leaves mature. Regardless the irradiance level, the photosynthetic performance of Purpurascens leaves did not differ from that observed in leaves of the Catuaí variety, providing no evidence that anthocyanins improve photosynthetic performance in coffee plants. To analyze the photoprotective action of anthocyanins, we evaluated the isomerization process for chlorogenic acids (CGAs) in coffee leaves exposed to UV-B radiation. No differences were observed in the total concentration of phenolic compounds in either variety before or after the UV treatment; however, we observed less degradation of CGA isomers in the Purpurascens leaves and a relative increase of cis-5-caffeoylquinic acid, a positional isomer of one of the most abundant form of CQA in coffee leaves, trans-5-caffeoylquinic acid, suggesting a possible protective role for anthocyanins in this purple coffee variety.
... Lúcio Flavo Lopes Vasconcelos I ; Rafael Vasconcelos Ribeiro II ; Ricardo Ferraz de Oliveira ... more ... Lúcio Flavo Lopes Vasconcelos I ; Rafael Vasconcelos Ribeiro II ; Ricardo Ferraz de Oliveira III ; Eduardo ... Ψ f ) nas faces leste e oeste da copa de laranjeiras 'Valência' em condições desequeiro. ... 2007); em pomares jovens, com menos de um ano de idade (Coelho Filho et al ...
... Biochem. 22: 280-283, 1968. Harley, PC, Loreto, F., Di Marco, G., Sharkey, TD: Theoretical co... more ... Biochem. 22: 280-283, 1968. Harley, PC, Loreto, F., Di Marco, G., Sharkey, TD: Theoretical considerations when estimating mesophyll conductance to CO2 flux by analysis of the response of photosynthesis to CO2. ... [In Portuguese.] Maurel, C., Verdoucq, L., Luu, D., Santoni,V ...
Resumo–O objetivo deste trabalho foi avaliar de que maneira a alta disponibilidade de fósforo no ... more Resumo–O objetivo deste trabalho foi avaliar de que maneira a alta disponibilidade de fósforo no solo afeta a fotossíntese eo crescimento de mudas de cafeeiro arábica (Coffea arabica). Mudas da cultivar Ouro Verde com aproximadamente quatro meses de idade, ...
Page 1. Water deficiency at different developmental stages of Glycine max Bragantia, Campinas, v.... more Page 1. Water deficiency at different developmental stages of Glycine max Bragantia, Campinas, v.67, n.1, p.43-49, 2008 43 WATER DEFICIENCY AT DIFFERENT DEVELOPMENTAL STAGES OF GLYCINE MAX CAN IMPROVE DROUGHT TOLERANCE (1) ...
This study evaluated the photosynthetic responses of seven tropical trees of different succession... more This study evaluated the photosynthetic responses of seven tropical trees of different successional groups under contrasting irradiance conditions, taking into account changes in gas exchange and chlorophyll a fluorescence. Although early successional species have shown higher values of CO2 assimilation (A) and transpiration (E), there was not a defined pattern of the daily gas exchange responses to high irradiance (FSL) among evaluated species. Cariniana legalis (Mart.) Kuntze (late secondary) and Astronium graveolens Jacq. (early secondary) exhibited larger reductions in daily-integrated CO2 assimilation (DIA) when transferred from medium light (ML) to FSL. On the other hand, the pioneer species Guazuma ulmifolia Lam. had significant DIA increase when exposed to FSL. The pioneers Croton spp. trended to show a DIA decrease around 19%, while Cytharexyllum myrianthum Cham. (pioneer) and Rhamnidium elaeocarpum Reiss. (early secondary) trended to increase DIA when transferred to FSL. Under this condition, all species showed dynamic photoinhibition, except for C. legalis that presented chronic photoinhibition of photosynthesis. Considering daily photosynthetic processes, our results supported the hypothesis of more flexible responses of early successional species (pioneer and early secondary species). The principal component analysis indicated that the photochemical parameters effective quantum efficiency of photosystem II and apparent electron transport rate were more suitable to separate the successional groups under ML condition, whereas A and E play a major role to this task under FSL condition.
The aim of this study was to determine which anthocyanins are related to the purple coloration of... more The aim of this study was to determine which anthocyanins are related to the purple coloration of young leaves in Coffea arabica var. Purpurascens and assess their impact on photosynthesis as compared to C. arabica var. Catuaí, with green leaves. Two delphinidin glicosides were identified and histological cross-sections showed they were located throughout the adaxial epidermis in young leaves, disappearing as the leaves mature. Regardless the irradiance level, the photosynthetic performance of Purpurascens leaves did not differ from that observed in leaves of the Catuaí variety, providing no evidence that anthocyanins improve photosynthetic performance in coffee plants. To analyze the photoprotective action of anthocyanins, we evaluated the isomerization process for chlorogenic acids (CGAs) in coffee leaves exposed to UV-B radiation. No differences were observed in the total concentration of phenolic compounds in either variety before or after the UV treatment; however, we observed less degradation of CGA isomers in the Purpurascens leaves and a relative increase of cis-5-caffeoylquinic acid, a positional isomer of one of the most abundant form of CQA in coffee leaves, trans-5-caffeoylquinic acid, suggesting a possible protective role for anthocyanins in this purple coffee variety.
... Lúcio Flavo Lopes Vasconcelos I ; Rafael Vasconcelos Ribeiro II ; Ricardo Ferraz de Oliveira ... more ... Lúcio Flavo Lopes Vasconcelos I ; Rafael Vasconcelos Ribeiro II ; Ricardo Ferraz de Oliveira III ; Eduardo ... Ψ f ) nas faces leste e oeste da copa de laranjeiras 'Valência' em condições desequeiro. ... 2007); em pomares jovens, com menos de um ano de idade (Coelho Filho et al ...
... Biochem. 22: 280-283, 1968. Harley, PC, Loreto, F., Di Marco, G., Sharkey, TD: Theoretical co... more ... Biochem. 22: 280-283, 1968. Harley, PC, Loreto, F., Di Marco, G., Sharkey, TD: Theoretical considerations when estimating mesophyll conductance to CO2 flux by analysis of the response of photosynthesis to CO2. ... [In Portuguese.] Maurel, C., Verdoucq, L., Luu, D., Santoni,V ...
Resumo–O objetivo deste trabalho foi avaliar de que maneira a alta disponibilidade de fósforo no ... more Resumo–O objetivo deste trabalho foi avaliar de que maneira a alta disponibilidade de fósforo no solo afeta a fotossíntese eo crescimento de mudas de cafeeiro arábica (Coffea arabica). Mudas da cultivar Ouro Verde com aproximadamente quatro meses de idade, ...
Page 1. Water deficiency at different developmental stages of Glycine max Bragantia, Campinas, v.... more Page 1. Water deficiency at different developmental stages of Glycine max Bragantia, Campinas, v.67, n.1, p.43-49, 2008 43 WATER DEFICIENCY AT DIFFERENT DEVELOPMENTAL STAGES OF GLYCINE MAX CAN IMPROVE DROUGHT TOLERANCE (1) ...
This study evaluated the photosynthetic responses of seven tropical trees of different succession... more This study evaluated the photosynthetic responses of seven tropical trees of different successional groups under contrasting irradiance conditions, taking into account changes in gas exchange and chlorophyll a fluorescence. Although early successional species have shown higher values of CO2 assimilation (A) and transpiration (E), there was not a defined pattern of the daily gas exchange responses to high irradiance (FSL) among evaluated species. Cariniana legalis (Mart.) Kuntze (late secondary) and Astronium graveolens Jacq. (early secondary) exhibited larger reductions in daily-integrated CO2 assimilation (DIA) when transferred from medium light (ML) to FSL. On the other hand, the pioneer species Guazuma ulmifolia Lam. had significant DIA increase when exposed to FSL. The pioneers Croton spp. trended to show a DIA decrease around 19%, while Cytharexyllum myrianthum Cham. (pioneer) and Rhamnidium elaeocarpum Reiss. (early secondary) trended to increase DIA when transferred to FSL. Under this condition, all species showed dynamic photoinhibition, except for C. legalis that presented chronic photoinhibition of photosynthesis. Considering daily photosynthetic processes, our results supported the hypothesis of more flexible responses of early successional species (pioneer and early secondary species). The principal component analysis indicated that the photochemical parameters effective quantum efficiency of photosystem II and apparent electron transport rate were more suitable to separate the successional groups under ML condition, whereas A and E play a major role to this task under FSL condition.
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