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Texto completo SciELO Brasil
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Id: biblio-1285547
Autor: Laboratory of Plant AnatomyMarques, Daniele Maria; Magalhães, Paulo César; Marriel, Ivanildo Evódio; Gomes Júnior, Carlos César; Silva, Adriano Bortolotti da; Souza, Thiago Corrêa de.
Título: Gas Exchange, Root Morphology and Nutrients in Maize Plants Inoculated with Azospirillum brasilense Cultivated Under Two Water Conditions
Fonte: Braz. arch. biol. technol;64:e21190580, 2021. tab, graf.
Idioma: en.
Projeto: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior.
Resumo: HIGHLIGHTS Azospirillum brasilense stimulates root growth in maize under water deficit. Maize inoculated with A. brasilense shows greater photosynthesis under drought conditions. Under water deficit, maize plants inoculated with A. brasilense showed greater water use efficiency (WUE).

Abstract The objective of this study was to evaluate the gas exchange, root morphology and nutrient concentration in maize plants inoculated with A. brasilense under two water conditions. The experiments were carried out in a greenhouse, one under irrigation and the other under water deficit. The treatments consisted of four A. brasilense inoculants (control (without inoculation), Az1 (CMS 7 + 26), Az2 (CMS 11 + 26) and Az3 (CMS 26 +42). At the V6 plant stage, water stress was imposed on maize plants for 15 days. The phytotechnical characteristics, gas exchange, root morphology, root dry matter and macronutrient analysis were evaluated after 15 days of water deficit imposition. The water deficit caused a reduction in the development of maize plants. The presence of A. brasilense Az1 under the same condition yielded higher photosynthesis, carboxylation efficiency, water use efficiency, and greater soil exploration with increased length, surface area and root volume of plants. Inoculation by A. brasilense increased root system volume by an average of 40 and 47% under irrigation and water deficit, respectively, when compared to non-inoculated plants. The inoculant Az1 attenuated the deleterious effects caused by drought and yielded the best growth of the root system, resulting in the tolerance of maize plants to water deficit.
Descritores: Fotossíntese
Consumo de Água (Saúde Ambiental)
Zea mays
Uso Eficiente da Água/métodos
Tipo de Publ: Estudo de Avaliação
Responsável: BR1.1 - BIREME


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Id: biblio-838970
Autor: Badshah, Syed Lal; Mabkhot, Yahia; Al-Showiman, Salim S.
Título: Photosynthesis at the far-red region of the spectrum in Acaryochloris marina
Fonte: Biol. Res;50:16, 2017. graf.
Idioma: en.
Resumo: Acaryochloris marina is an oxygenic cyanobacterium that utilizes far-red light for photosynthesis. It has an expanded genome, which helps in its adaptability to the environment, where it can survive on low energy photons. Its major light absorbing pigment is chlorophyll d and it has α-carotene as a major carotenoid. Light harvesting antenna includes the external phycobilin binding proteins, which are hexameric rods made of phycocyanin and allophycocyanins, while the small integral membrane bound chlorophyll binding proteins are also present. There is specific chlorophyll a molecule in both the reaction center of Photosystem I (PSI) and PSII, but majority of the reaction center consists of chlorophyll d. The composition of the PSII reaction center is debatable especially the role and position of chlorophyll a in it. Here we discuss the photosystems of this bacterium and its related biology.
Descritores: Fotossíntese/fisiologia
Clorofila/biossíntese
Cianobactérias/metabolismo
-Adaptação Fisiológica
Genoma Bacteriano
Cianobactérias/genética
Tipo de Publ: Revisão
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1003338
Autor: Rezende, Uiara Costa; Moreira, Ana Silvia Franco Pinheiro; Kuster, Vinícius Coelho; Oliveira, Denis Coelho de.
Título: Structural, histochemical and photosynthetic profiles of galls induced by Eugeniamyia dispar (Diptera: Cecidomyiidae) on the leaves of Eugenia uniflora (Myrtaceae) / Perfiles estructurales, histoquímicos y fotosintéticos de las agallas inducidas por Eugeniamyia dispar (Diptera: Cecidomyiidae) en las hojas de Eugenia uniflora (Myrtaceae)
Fonte: Rev. biol. trop;66(4):1469-1480, oct.-dic. 2018. tab, graf.
Idioma: en.
Resumo: Abstract Gall-inducing insects manipulate the structural, histochemical and physiological profiles of host-plant tissues to develop galls. We evaluated galls induced by Eugeniamyia dispar on the leaves of Eugenia uniflora in an attempt to answer the following questions: (i) How does this gall-inducing insect change the structural and histochemical profiles of the host-plant organ? (ii) Despite structural changes, can gall tissues maintain photosynthetic activity? Starch, proteins, reducing sugars and reactive oxygen species were detected mainly in the nutritive tissue surrounding the larval chamber. Despite structural changes, the galls induced by E. dispar on E. uniflora retain chlorophyllous tissue, although its amount and photosynthetic activity are less than that of non-galled leaves. This reduced photosynthetic activity, in association with the presence of large intercellular spaces, could improve gas diffusion and, consequently, avoid hypoxia and hypercarbia in gall tissue.(AU)

Resumen Los insectos que inducen las agallas manipulan los perfiles estructurales, histoquímicos y fisiológicos de los tejidos de la planta hospedera para su desarrollo. Nosotros evaluamos las agallas inducidas por Eugeniamyia dispar en las hojas de Eugenia uniflora en un intento de responder las siguientes preguntas: (i) ¿Cómo este insecto inductor de agallas cambia los perfiles estructurales e histoquímicos en el órgano de la planta hospedera? (ii) A pesar de las modificaciones estructurales, ¿pueden los tejidos de la agalla mantener la actividad fotosintética? El almidón, las proteínas, los azúcares reductores y las especies reactivas de oxígeno se detectaron principalmente en la capa de tejido nutritivo que rodea a la cavidad larval. A pesar de las modificaciones estructurales, las agallas inducidas por E. dispar en E. uniflora retienen su tejido clorofílico, aunque su cantidad y actividad fotosintética son menores que en las hojas no agalladas. Esta actividad fotosintética reducida, asociado a la presencia de grandes espacios intercelulares, pueden mejorar la difusión de gases y, en consecuencia, evitar la hipoxia y la hipercapnia en los tejidos de las agallas.(AU)
Descritores: Fotossíntese
Dípteros
Eugenia
Clorofila A
-Hipóxia
Responsável: BR1.1 - BIREME


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Texto completo SciELO Chile
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Id: biblio-950839
Autor: Chen, Yuhang; Liu, Li; Guo, Qiaosheng; Zhu, Zaibiao; Zhang, Lixia.
Título: Effects of different water management options and fertilizer supply on photosynthesis, fluorescence parameters and water use efficiency of Prunella vulgaris seedlings
Fonte: Biol. Res;49:1-9, 2016. graf, tab.
Idioma: en.
Projeto: Nature Science Foundation of China; . China Postdoctoral Science Foundation; . Sichuan Provincial Education Department. Scientific Research Fund of.
Resumo: BACKGROUND: Prunella vulgaris L. is a medical plant cultivated in sloping, sun-shaded areas in China. Recently, owing to air-environmental stress, especially drought stress strongly inhibits plant growth and development, the appropriate fertilizer supply can alleviate these effects. However, these is little information about their effects on P. vulgaris growing in arid and semi-arid areas with limited water and fertilizer supply. RESULTS: In this study, water stress decreased the photosynthetic pigment contents, inhibited photosynthetic efficiency, induced photodamage in photosystem 2 (PS2), and decreased leaf instantaneous WUE (WUEi). The decreased net photosynthetic rate (Pn) under medium drought stress compared with the control might result from stomatal limitations. However, fertilizer supply improved photosynthetic capacity by increasing the photosynthetic pigment contents and enhancing photosynthetic efficiency under water deficit. Moreover, medium fertilization also increased WUEi under the two water conditions, but fertilizer supply did little to alleviate the PS2 photodamage caused by drought stress. Hence, drought stress was the primary limitation in the photosynthetic process of P. vulgaris seedlings, while the photosynthetic characteristics of the seedlings exhibited positive responses to fertilizer supply. CONCLUSIONS: Appropriate fertilizer supply is recommended to improve photosynthetic efficiency, enhance WUEi and alleviate photodamage under drought stress.
Descritores: Fotossíntese/fisiologia
Água/fisiologia
Prunella/crescimento & desenvolvimento
Plântula/crescimento & desenvolvimento
Fertilizantes
-Estresse Fisiológico
Fatores de Tempo
Clorofila/fisiologia
Análise de Variância
Ritmo Circadiano
Folhas de Planta
Secas
Fluorescência
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-950857
Autor: Liu, Yu; Wang, Lu; Liu, Heng; Zhao, Rongrong; Liu, Bin; Fu, Quanjuan; Zhang, Yuanhu.
Título: The antioxidative defense system is involved in the premature senescence in transgenic tobacco (Nicotiana tabacum NC89)
Fonte: Biol. Res;49:1-5, 2016. ilus, graf, tab.
Idioma: en.
Projeto: National Natural Science Foundation of China.
Resumo: BACKGROUND: α-Farnesene is a volatile sesquiterpene synthesized by the plant mevalonate (MVA) pathway through the action of α-farnesene synthase. The α-farnesene synthase 1 (MdAFS1) gene was isolated from apple peel (var. white winterpearmain), and transformed into tobacco (Nicotiana tabacum NC89). The transgenic plants had faster stem elongation during vegetative growth and earlier flowering than wild type (WT). Our studies focused on the transgenic tobacco phenotype. RESULTS: The levels of chlorophyll and soluble protein decreased and a lower seed biomass and reduced net photosynthetic rate (Pn) in transgenic plants. Reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) and superoxide radicals (O2._) had higher levels in transgenics compared to controls. Transgenic plants also had enhanced sensitivity to oxidative stress. The transcriptome of 8-week-old plants was studied to detect molecular changes. Differentially expressed unigene analysis showed that ubiquitin-mediated proteolysis, cell growth, and death unigenes were upregulated. Unigenes related to photosynthesis, antioxidant activity, and nitrogen metabolism were downregulated. Combined with the expression analysis of senescence marker genes, these results indicate that senescence started in the leaves of the transgenic plants at the vegetative growth stage. CONCLUSIONS: The antioxidative defense system was compromised and the accumulation of reactive oxygen species (ROS) played an important role in the premature aging of transgenic plants.
Descritores: Tabaco/fisiologia
Plantas Geneticamente Modificadas/fisiologia
Antioxidantes/fisiologia
-Fotossíntese/fisiologia
Sesquiterpenos/análise
Sesquiterpenos/metabolismo
Fatores de Tempo
Tabaco/genética
Marcadores Genéticos
Expressão Gênica/fisiologia
Plantas Geneticamente Modificadas/genética
Espécies Reativas de Oxigênio/análise
Espécies Reativas de Oxigênio/metabolismo
Superóxidos/análise
Superóxidos/metabolismo
Folhas de Planta/fisiologia
Estresse Oxidativo/fisiologia
Regulação da Expressão Gênica de Plantas/fisiologia
Reação em Cadeia da Polimerase em Tempo Real
Peróxido de Hidrogênio/análise
Peróxido de Hidrogênio/metabolismo
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-950886
Autor: Vorphal, María Alejandra; Bruna, Carola; Wandersleben, Traudy; Dagnino-Leone, Jorge; Lobos-González, Francisco; Uribe, Elena; Martínez-Oyanedel, José; Bunster, Marta.
Título: Molecular and functional characterization of ferredoxin NADP(H) oxidoreductase from Gracilaria chilensis and its complex with ferredoxin
Fonte: Biol. Res;50:39, 2017. tab, graf.
Idioma: en.
Projeto: FONDECYT.
Resumo: BACKGROUND: Ferredoxin NADP(H) oxidoreductases (EC 1.18.1.2) (FNR) are flavoenzymes present in photosynthetic organisms; they are relevant for the production of reduced donors to redox reactions, i.e. in photosynthesis, the reduction of NADP+ to NADPH using the electrons provided by Ferredoxin (Fd), a small FeS soluble protein acceptor of electrons from PSI in chloroplasts. In rhodophyta no information about this system has been reported, this work is a contribution to the molecular and functional characterization of FNR from Gracilaria chilensis, also providing a structural analysis of the complex FNR/Fd. METHODS: The biochemical and kinetic characterization of FNR was performed from the enzyme purified from phycobilisomes enriched fractions. The sequence of the gene that codifies for the enzyme, was obtained using primers designed by comparison with sequences of Synechocystis and EST from Gracilaria. 5'RACE was used to confirm the absence of a CpcD domain in FNRPBS of Gracilaria chilensis. A three dimensional model for FNR and Fd, was built by comparative modeling and a model for the complex FNR: Fd by docking. RESULTS: The kinetic analysis shows KMNADPH of 12.5 M and a kcat of 86 s-1, data consistent with the parameters determined for the enzyme purified from a soluble extract. The sequence for FNR was obtained and translated to a protein of 33646 Da. A FAD and a NADP+ binding domain were clearly identified by sequence analysis as well as a chloroplast signal sequence. Phycobilisome binding domain, present in some cyanobacteria was absent. Transcriptome analysis of Gch revealed the presence of two Fd; FdL and FdS, sharing the motif CX5CX2CX29X. The analysis indicated that the most probable partner for FNR is FdS. CONCLUSION: The interaction model produced, was consistent with functional properties reported for FNR in plants leaves, and opens the possibilities for research in other rhodophyta of commercial interest.
Descritores: Gracilaria/enzimologia
Ferredoxina-NADP Redutase/química
Ferredoxinas/metabolismo
-Oxirredução
Fotossíntese/fisiologia
Sequência de Aminoácidos
Gracilaria/química
Eletroforese em Gel de Poliacrilamida
Ferredoxina-NADP Redutase/genética
Ferredoxina-NADP Redutase/farmacocinética
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-983947
Autor: Contreras, Rodrigo A; Pizarro, Marisol; Köhler, Hans; Sáez, Claudio A; Zúñiga, Gustavo E.
Título: Copper stress induces antioxidant responses and accumulation of sugars and phytochelatins in Antarctic Colobanthus quitensis (Kunth) Bartl
Fonte: Biol. Res;51:48, 2018. graf.
Idioma: en.
Projeto: Fondecyt; . Basal Program for Centers of Excellence.
Resumo: BACKGROUND: In field, C. quitensis Is subjected to many abiotic extreme environmental conditions, such as low temperatures, high UV-B, salinity and reduced water potentials, but not metal or metalloid high concentrations in soil, however, other members of Caryophyllaceae family have tolerance to high concentrations of metals, this is the case of Silene genre. In this work, we hypothesize that C. quitensis have the same mechanisms of Silene to tolerate metals, involving accumulation and induction of antioxidant systems, sugar accumulation and the induction of thiols such as phytochelatins to tolerate. RESULTS: The results showing an effective antioxidant defensive machinery involving non-enzymatic antioxidants such as phenolics, GSH and ascorbic acid, in another hand, GSH-related oligomers (phytochelatins) and sugars was induced as a defensive mechanism. CONCLUSIONS: Colobanthus quitensis exhibits certain mechanisms to tolerate copper in vitro demonstrating its plasticity to tolerate several abiotic stress conditions.
Descritores: Cobre/farmacologia
Caryophyllaceae/metabolismo
Açúcares/análise
Fitoquelatinas/metabolismo
Antioxidantes/fisiologia
-Fotossíntese
Estresse Oxidativo/fisiologia
Caryophyllaceae/química
Açúcares/metabolismo
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1011419
Autor: Chen, Yuhang; Zhang, Xuerong; Guo, Qiaosheng; Cao, Liping; Qin, Qin; Li, Chen; Zhao, Miao; Wang, Wenming.
Título: Plant morphology, physiological characteristics, accumulation of secondary metabolites and antioxidant activities of Prunella vulgaris L. under UV solar exclusion
Fonte: Biol. Res;52:17, 2019. tab.
Idioma: en.
Projeto: National Nature Science Foundation of China; . China Postdoctoral Science Foundation; . Basic Research Program of Sichuan Province of China; . Sichuan Province Undergraduates Innovating Experimentation Project.
Resumo: BACKGROUND: Prunella vulgaris L. has been an important medicinal plant for the treatment of thyroid gland malfunction and mastitis in China for over 2000 years. There is an urgent need to select effective wavelengths for greenhouse cultivation of P. vulgaris as light is a very important factor in P. vulgaris growth. Here, we described the effects of natural light (control) and UV solar exclusion on the morphological and physiological traits, secondary metabolites contents and antioxidant activities of P. vulgaris. RESULTS: The results showed that UV solar exclusion resulted in remarkable alterations to morphological and biomass traits; significantly reduced the chlorophyll a, chlorophyll b and total chlorophyll contents; significantly enhanced the ratio of chlorophyll a to b; and significantly increased the carotenoid and anthocyanin contents in P. vulgaris. UV solar exclusion significantly increased the catalase (CAT) and peroxidase (POD) activities, increased superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities and slightly decreased the glutathione (GSH) content. UV solar exclusion significantly increased the soluble sugar and H2O2 contents and increased the soluble protein content but significantly decreased the proline content and slightly decreased the MDA content. The secondary metabolite contents (total phenolics, rosmarinic acid, caffeic acid, hyperoside, ursolic acid and oleanolic acid) and in vitro antioxidative properties (DPPH· and ABTS·+scavenging activities) were significantly increased in P. vulgaris spicas under UV solar exclusion. Additionally, the total polysaccharide and total flavonoids contents were slightly increased by UV solar exclusion. The salviaflaside content was significantly reduced by UV solar exclusion. CONCLUSION: Our study demonstrated that P. vulgaris activates several antioxidant defence systems against oxidative damage caused by UV solar exclusion.
Descritores: Fotossíntese/fisiologia
Prunella/metabolismo
Antocianinas/biossíntese
Antioxidantes/metabolismo
-Raios Ultravioleta
Prunella/efeitos da radiação
Prunella/química
Antioxidantes/efeitos da radiação
Responsável: CL1.1 - Biblioteca Central


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Texto completo SciELO Costa Rica
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Id: biblio-1041897
Autor: Gamboa-Mendoza, Adriana Patricia; Delgadillo-Martínez, Julián; Almaraz-Suárez, Juan José; Robledo-Paz, Alejandrina; Alarcón, Alejandro.
Título: Respuesta de Fragaria mexicana y comunidades microbianas rizosféricas al aumento de temperature / Response of Fragaria Mexicana and rhizophere microbial communitites to temperature increase
Fonte: Rev. biol. trop;67(1):94-106, Jan.-Mar. 2019. tab, graf.
Idioma: es.
Resumo: Resumen Para los próximos 100 años se pronostica un incremento en la temperatura del planeta de casi 4 °C, lo cual pondrá en riesgo las especies que no logren adaptarse. En esta investigación se determinaron las respuestas morfofisiológicas de F. mexicana y los cambios en la población de bacterias fijadoras de nitrógeno atmosférico (BFN) asociadas a sus raíces, debido a dos condiciones ambientales con diferencias medias de temperatura de 5.1 oC: invernadero (temperatura alta, TA) y campo abierto (temperatura baja, TB); y con cuatro tratamientos: sin inocular (T), inoculadas con la cepa ocho (CP8), cepa cuatro (CP4) y con ambas cepas (CP8 + 4). Las BFN fueron aisladas de la rizosfera de F. mexicana y transformadas genéticamente con reporteros, para cuantificar la población al final del experimento. Se midió el peso seco de la parte aérea y la raíz, la tasa de asimilación de CO2 (A), el inicio de la floración, el número de flores y frutos; y la persistencia de las bacterias fijadoras de N atmosférico (BFN). Además, se evaluó la concentración de NO3, NH4, P y materia orgánica (MO) en el sustrato, al inicio y final del experimento. Las plantas sometidas a alta temperatura presentaron mayor peso seco de la parte aérea y fotosíntesis; con una disminución en el peso seco de la raíz, y en el número de flores y frutos. La MO en el sustrato disminuyó, mientras que la disponibilidad de NO3, NH4 y P aumentó. El incremento de temperatura y la mayor presencia de N en el substrato provocaron reducción en la población de BFN. Estos resultados sugieren que temperaturas altas estimulan el crecimiento de F. mexicana y tienen un impacto negativo sobre su reproducción y en las BFN asociadas a sus raíces.(AU)

Abstract The earth could experience a warming of 4 °C in the next one hundred years. This would put at risk the plants that can´t adapt. Fragaria mexicana is an endemic plant of temperate forest of Mexico. The response of this wild strawberry to temperature increasing has not been studied and could play an important role for event of global warming. This study determinate the morphological and physiological responses of F. mexicana and changes in the N2-fixing bacteria (BFN) population on its roots, due to two environmental conditions with differences of temperature 5.1 °C: greenhouse (high temperature, TA) and open land (low temperature, TB); and with four free-living nitrogen-fixing bacteria (BFN) treatments: non-inoculated (T), inoculated with strain eight (CP8), strain four (CP4), and strains eight and four mixed (CP8 + 4). BFN were isolated from the rhizosphere of F. mexicana and were genetically transformed with reporters to quantify the population at the end of the experiment. NO3, NH4 and P and organic matter (MO) in the substrate were determined at beginning and finish of the experiment. Shoot and root dry weight, photosynthetic rate, flowering and fructification starting, flowers and fruits number, were measured. Shoot dry weight and photosynthetic rate were lower in TB than TA, decreasing 3.1 g and 0.94 µmol m-2 s-1, respectively. Root dry weight was 3.0 g less in TA compared with TB. Number flowers decrease in 40.89 % and number fruits in 38.11 % on TA than TB. F. mexicana plants start flowering 14 days previously in TB than TA. MO in the substrate decrease in TA, while the concentration of NO3, NH4 and P, increased. Population of BFN was lower in TA. Results obtained indicated that higher temperature promotes the growth of F. mexicana and reduce its reproduction and BNF population associated with its roots.(AU)
Descritores: Fotossíntese
Matéria Orgânica
Aquecimento Global
Bactérias Fixadoras de Nitrogênio
-México
Responsável: BR1.1 - BIREME


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Id: biblio-1146497
Autor: Mota, Leandro Henrique de Sousa; Scalon, Silvana de Paula Quintão; Dresch, Daiane Mugnol; Silva, Cesar José da.
Título: Emergence and physiological behavior of provenances of pinhão manso in function of level of aluminum / Surgimento e comportamento fisiológico de procedências de pinhão manso em função do nível de alumínio
Fonte: Biosci. j. (Online);36(3):702-712, 01-05-2020. tab, graf.
Idioma: en.
Resumo: The aluminum in high levels in the soil affects the emergence, growth, and development of various species. Therefore, the objective of this study was to evaluate the emergence and physiological behavior of four provenances of Jatropha curcas subjected to different levels of aluminum. The experiment was performed in a greenhouse in a completely randomized design, with four levels of aluminum in the soil (8.2, 16.5, 24.0 mmolc·dm-3 and control) and four provenances of J. curcas seeds (P1 = Dourados-MS, P2 = Montes Claros-MG, P3 = Alta Floresta-MT, and P4 = Petrolina-PE); the effects of aluminum toxicity were investigated in 25, 50, 75, and 100 days after emergence. The levels of aluminum in the soil were collected from the initial soil correction, which featured an aluminum level of 24.0 mmolc dm-3. The seedling emergence was not affected by treatment with aluminum; however, the height and leaf area of P1, P2, and P3 were reduced with increasing levels of aluminum. The emergence and vigor of J. curcas seeds were not influenced by the differences in the origins of the seeds or by the aluminum levels evaluated. Gas exchanges were affected negatively by aluminum and the responses of the chlorophyll a fluorescence indicate harmful effect in the photosynthetic apparatus. The seeds of origin P4 (Petrolina-PE) has increased tolerance to stress conditions.

O alumínio em níveis elevados no solo afeta a emergência, o crescimento e o desenvolvimento de diversas espécies. Diante disso, o objetivo desse trabalho foi avaliar a emergência e o comportamento fisiológico de quatro procedências de Jatropha curcas submetidas a diferentes níveis de alumínio. O experimento foi conduzido em casa de vegetação, em delineamento inteiramente casualizado, com quatro níveis de alumínio no solo (8,2; 16,5 e 24,0 mmolc dm-3 e o controle) e quatro procedências de sementes de J. curcas (P1 = Dourados-MS P2 = Montes Claros-MG, P3 = Alta Floresta-MT e P4 = Petrolina-PE), e os efeitos da toxicidade do alumínio foram investigados aos 25, 50, 75 e 100 dias após a emergência. A emergência das plântulas não foi afetada pelo tratamento com alumínio; no entanto, a altura e a área foliar de P1, P2 e P3 foram reduzidas com níveis crescentes de alumínio. A emergência e o vigor das plântulas das procedências não foram afetados pelos níveis de alumínio avaliados. A taxa fotossintética, taxa de transpiração e condutância estomática também foram reduzidas quando as plantas foram cultivadas em solo contendo altas níveis de alumínio. As plantas P4 foram menos sensíveis aos níveis crescentes de alumínio.
Descritores: Solo
Jatropha
Alumínio
-Fotossíntese
Análise do Solo
Crescimento e Desenvolvimento
Controle
Toxicidade
Clorofila A
Responsável: BR396.1 - Biblioteca Central



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