Responses of antioxidant enzymes, photosynthetic pigments and carbohydrates in micropropagated Pitcairnia encholirioides L.B. Sm. (Bromeliaceae) under ex vitro water deficit and after rehydration / Respostas de enzimas antioxidantes, pigmentos fotossintéticos e carboidratos em Pitcairnia encholirioides L.B. Sm. (Bromeliaceae) micropropagadas, sob déficit hídrico ex vitro e após reidratação

In this study, the activities of antioxidant enzymes, photosynthetic pigments, proline and carbohydrate contents in Pitcairnia encholirioides under ex vitro conditions of water deficit were evaluated. Results show that plants under progressive water stress, previously in vitro cultured in media supplemented with 30 g L-1 sucrose and GA3, accumulated more proline and increased peroxidase (POD) activity and the contents of photosynthetic pigments and carbohydrates. For plants previously in vitro cultured with 15 g L-1 sucrose and NAA, no differences were found for proline content and there were reductions in activities of peroxidase (POD), catalase (CAT) and poliphenoloxidase (PPO), and in contents of carbohydrates, with progress of ex vitro water deficit. After rehydration, plants showed physiological recovery, with enzymatic activities and contents of metabolites similar to those found in the controls not submitted to dehydration, regardless of the previous in vitro culture conditions. These results show that micropropagated P. encholirioides has high tolerance to dehydration once in ex vitro conditions, which can ensure the survival of plants from tissue culture when transferred to its natural environment, emphasizing the importance of such biotechnology for the propagation of endangered species.

Neste estudo, foram avaliadas as atividades de enzimas antioxidantes, pigmentos fotossintéticos, conteúdo de prolina e carboidratos em Pitcairnia encholirioides sob déficit hídrico em condições ex vitro. Os resultados mostraram que as plantas sob estresse hídrico progressivo, previamente cultivadas in vitro em meio de cultura suplementado com 30 g L-1 de sacarose e GA3 acumularam mais prolina e aumentaram a atividade da peroxidase (POD) e os teores de pigmentos fotossintéticos e carboidratos. Para plantas previamente cultivadas in vitro com 15 g L-1 de sacarose e ANA, não foram encontradas diferenças nos conteúdos de prolina e houve reduções nas atividades da peroxidase (POD), catalase (CAT) e polifenoloxidase (PPO), e no conteúdo de carboidratos, com o progresso do déficit hídrico ex vitro. Após a reidratação, as plantas apresentaram recuperação fisiológica, com atividades enzimáticas e conteúdo de metabólitos semelhantes aos encontrados nos controles não sujeitos à desidratação, independentemente das condições de cultivo in vitro. Estes resultados mostram que P. encholirioides micropropagada tem alta tolerância à desidratação uma vez em condições ex vitro, o que pode garantir a sobrevivência de plantas provenientes da cultura de tecidos quando transferidas para seu ambiente natural, enfatizando a importância desta biotecnologia para a propagação de espécies ameaçadas.

Responses of antioxidant enzymes, photosynthetic pigments and carbohydrates in micropropagated Pitcairnia encholirioides L.B. Sm. (Bromeliaceae) under ex vitro water deficit and after rehydration / Respostas de enzimas antioxidantes, pigmentos fotossintéticos e carboidratos em Pitcairnia encholirioides L.B. Sm. (Bromeliaceae) micropropagadas, sob déficit hídrico ex vitro e após reidratação

Abstract In this study, the activities of antioxidant enzymes, photosynthetic pigments, proline and carbohydrate contents in Pitcairnia encholirioides under ex vitro conditions of water deficit were evaluated. Results show that plants under progressive water stress, previously in vitro cultured in media supplemented with 30 g L-1 sucrose and GA3, accumulated more proline and increased peroxidase (POD) activity and the contents of photosynthetic pigments and carbohydrates. For plants previously in vitro cultured with 15 g L-1 sucrose and NAA, no differences were found for proline content and there were reductions in activities of peroxidase (POD), catalase (CAT) and poliphenoloxidase (PPO), and in contents of carbohydrates, with progress of ex vitro water deficit. After rehydration, plants showed physiological recovery, with enzymatic activities and contents of metabolites similar to those found in the controls not submitted to dehydration, regardless of the previous in vitro culture conditions. These results show that micropropagated P. encholirioides has high tolerance to dehydration once in ex vitro conditions, which can ensure the survival of plants from tissue culture when transferred to its natural environment, emphasizing the importance of such biotechnology for the propagation of endangered species.

Resumo Neste estudo, foram avaliadas as atividades de enzimas antioxidantes, pigmentos fotossintéticos, conteúdo de prolina e carboidratos em Pitcairnia encholirioides sob déficit hídrico em condições ex vitro. Os resultados mostraram que as plantas sob estresse hídrico progressivo, previamente cultivadas in vitro em meio de cultura suplementado com 30 g L-1 de sacarose e GA3 acumularam mais prolina e aumentaram a atividade da peroxidase (POD) e os teores de pigmentos fotossintéticos e carboidratos. Para plantas previamente cultivadas in vitro com 15 g L-1 de sacarose e ANA, não foram encontradas diferenças nos conteúdos de prolina e houve reduções nas atividades da peroxidase (POD), catalase (CAT) e polifenoloxidase (PPO), e no conteúdo de carboidratos, com o progresso do déficit hídrico ex vitro. Após a reidratação, as plantas apresentaram recuperação fisiológica, com atividades enzimáticas e conteúdo de metabólitos semelhantes aos encontrados nos controles não sujeitos à desidratação, independentemente das condições de cultivo in vitro. Estes resultados mostram que P. encholirioides micropropagada tem alta tolerância à desidratação uma vez em condições ex vitro, o que pode garantir a sobrevivência de plantas provenientes da cultura de tecidos quando transferidas para seu ambiente natural, enfatizando a importância desta biotecnologia para a propagação de espécies ameaçadas.

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)

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)

Effect of Thiourea on Physiological Performance of Two Salt Affected Rice (Oryza sativa L.) Cultivars

Aims: The aim of the experiment was to investigate the effect of thiourea on physiological characteristics of two rice (Oryza sativa L.) varieties under impact of salinity. Study Design: Experiment includes two rice varieties named as B-515 and KS-282, salinity level of 150 mM, thiourea of 0.25 mM alone and in combination were arranged in a completely randomized design (CRD). Place and Duration of Study: Old Botanical Garden, University of Agriculture Faisalabad, Pakistan, between 4th July and 21st August 2015. Methodology: Transplants of two rice varieties, Basmati-515 and KS-282 were exposed to salinity (150 mM) and thiourea (0.25 mM) after one month of transplanting in a Completely Randomized Design with three replications. Harvesting data was taken that include fresh and dry weights, leaf area, number of tillers, photosynthetic pigments, photosynthetic rate, transpiration rate, stomatal and substomatal conductance, water use efficiency and intrinsic CO2 concentration as well as chlorophyll contents in two rice varieties. Results: Thiourea treatment enhanced photosynthetic efficiency of Basmati-515 more than KS-282 by improving the chlorophyll and carotenoid contents and gas exchange attributes more than control. Conclusion: Salinity profoundly affect the physiological performance of two rice varieties especially that of KS-282, while 0.25 mM thiourea application unable to mitigate the effect of salinity but thiourea alone proved to be beneficial for both the rice varieties.

Water stress effects on chlorophyll fluorescence and chlorophyll content in sugarcane cultivars with contrasting tolerance / Efeitos do estresse hídrico na fluorescência e conteúdo de clorofila em cultivares de cana-de-açúcar com tolerância contrastante

One way to minimize the impacts caused by water deficit (WD) in agriculture is the use of tolerant cultivars. The physiological evaluation of plants through the potential quantum efficiency of photosystem II (Fv/Fm) and estimated chlorophyll content (SPAD index) can be an effective tool in the selection and recommendation of water deficit-tolerant cultivars. Within this context, the aim of this study was to evaluate the physiological responses of sugarcane cultivars classified as tolerant or susceptible to water deficit. The experiment was carried out near the city of Jaú, SP, Brazil in a greenhouse, between July and December 2013. The experimental design was completely randomized in a 4 x 2 factorial arrangement, with four replications. We studied four sugarcane cultivars: RB72454, RB855453 (prone to WD), SP81-3250 and SP83-2847 (WD-tolerant) in two water management regimes (with and without deficit). WD reduced stems dry mass of all cultivars, however, the greatest decreases were observed in susceptible cultivars to WD, where the decrease was 58.3 and 74.5% for cultivars RB855443 and RB72454, respectively. As for the SP81-3250 and SP83-2847 cultivars (tolerant), the reduction was 44.1 and 47.7%, respectively. For water deficit-tolerant cultivars, there was lower reduction in potential quantum efficiency of photosystem II and SPAD index; therefore, the physiological characteristics (Fv/Fm and SPAD index) are features that can aid the identification and selection of water deficit tolerant cultivars, and also help the recommendation of these cultivars for harsh environments, minimizing the effects of water deficit on stem yield on the sugarcane crop.

Uma forma de minimizar os impactos causados pelo déficit hídrico (DH) na agricultura é o uso de cultivares tolerantes. A avaliação fisiológica das plantas através da eficiência quântica potencial do fotossistema II (Fv/Fm) e do índice SPAD pode se tornar uma ferramenta eficiente na seleção e recomendação de cultivares tolerantes ao déficit hídrico. Com base nesse contexto, o objetivo deste trabalho foi avaliar as respostas fisiológicas de cultivares de cana-de-açúcar classificadas como tolerantes e susceptíveis ao déficit hídrico. O experimento foi realizado na região do município de Jaú/SP/Brasil em casa de vegetação, entre os meses de julho e dezembro de 2013. O delineamento experimental foi inteiramente casualizado no esquema fatorial 4 x 2, com quatro repetições. Foram estudadas quatro cultivares de cana-de-açúcar: RB72454, RB855453 (susceptíveis ao DH), SP81-3250 e SP83-2847 (tolerantes ao DH) em dois regimes hídricos (com e sem déficit). O DH reduziu a massa seca dos colmos de todas cultivares, porém, as maiores quedas foram observadas nas cultivares susceptíveis ao DH, em que nas cultivares RB855443 e RB72454 a queda foi de 58,3 e 74,5%, respectivamente. Já para as cultivares SP81-3250 e SP83-2847 (tolerantes), a redução foi de 44,1 e 47,7%, respectivamente. As cultivares tolerantes ao déficit hídrico tiveram menor redução na eficiência quântica potencial do fotossistema II e no índice SPAD, demonstrando, portanto, que os parâmetros fisiológicos (Fv/Fm e índice SPAD) são características que podem auxiliar a identificação e seleção de cultivares tolerantes ao déficit hídrico, e ainda, auxiliar a recomendação dessas cultivares para ambientes desfavoráveis, minimizando os efeitos do déficit hídrico sobre o rendimento de colmos na cultura da cana-de-açúcar.

Responses of antioxidant enzymes, photosynthetic pigments and carbohydrates in micropropagated Pitcairnia encholirioides L.B. Sm. (Bromeliaceae) under ex vitro water deficit and after rehydration

Abstract In this study, the activities of antioxidant enzymes, photosynthetic pigments, proline and carbohydrate contents in Pitcairnia encholirioides under ex vitro conditions of water deficit were evaluated. Results show that plants under progressive water stress, previously in vitro cultured in media supplemented with 30 g L-1 sucrose and GA3, accumulated more proline and increased peroxidase (POD) activity and the contents of photosynthetic pigments and carbohydrates. For plants previously in vitro cultured with 15 g L-1 sucrose and NAA, no differences were found for proline content and there were reductions in activities of peroxidase (POD), catalase (CAT) and poliphenoloxidase (PPO), and in contents of carbohydrates, with progress of ex vitro water deficit. After rehydration, plants showed physiological recovery, with enzymatic activities and contents of metabolites similar to those found in the controls not submitted to dehydration, regardless of the previous in vitro culture conditions. These results show that micropropagated P. encholirioides has high tolerance to dehydration once in ex vitro conditions, which can ensure the survival of plants from tissue culture when transferred to its natural environment, emphasizing the importance of such biotechnology for the propagation of endangered species.

Resumo Neste estudo, foram avaliadas as atividades de enzimas antioxidantes, pigmentos fotossintéticos, conteúdo de prolina e carboidratos em Pitcairnia encholirioides sob déficit hídrico em condições ex vitro. Os resultados mostraram que as plantas sob estresse hídrico progressivo, previamente cultivadas in vitro em meio de cultura suplementado com 30 g L-1 de sacarose e GA3 acumularam mais prolina e aumentaram a atividade da peroxidase (POD) e os teores de pigmentos fotossintéticos e carboidratos. Para plantas previamente cultivadas in vitro com 15 g L-1 de sacarose e ANA, não foram encontradas diferenças nos conteúdos de prolina e houve reduções nas atividades da peroxidase (POD), catalase (CAT) e polifenoloxidase (PPO), e no conteúdo de carboidratos, com o progresso do déficit hídrico ex vitro. Após a reidratação, as plantas apresentaram recuperação fisiológica, com atividades enzimáticas e conteúdo de metabólitos semelhantes aos encontrados nos controles não sujeitos à desidratação, independentemente das condições de cultivo in vitro. Estes resultados mostram que P. encholirioides micropropagada tem alta tolerância à desidratação uma vez em condições ex vitro, o que pode garantir a sobrevivência de plantas provenientes da cultura de tecidos quando transferidas para seu ambiente natural, enfatizando a importância desta biotecnologia para a propagação de espécies ameaçadas.

Effect of folia application of aminoacids on pant yield and some physiologicaal parameters in bean plants irrigated with seawater / Efecto de la aplicación foliar de aminoácidos sobre el rendimiento y parámetros fisiológicos en plantas de haba irrigadas con agua de mar

Salinity decreases yield in arid and semi-arid areas. With increasing demand for irrigation water, alternative sources are being sought. Seawater salinity was previously considered unusable for irrigation. However, this water can be used successfully to grow crops under certain conditions. Amino acids is well known biostimulant which has positive effects on plant growth and yield, and significantly mitigates the injuries caused by abiotic stresses. Therefore, in the present study, the effect of exogenously treatment amino acid on faba bean plant growing under seawater salt stress was investigated. Reduction of salinity damage in faba bean by using a mixture of amino acids to improve morphological and biochemical parameters, and thus raising the level of plant yield was tested. A pot experiment was conducted to alleviate the harmful effects of seawater salinity on faba bean cv. Giza 843 by foliar spraying of an amino acid mixture with different concentrations (0.0, 500, 1000 or 1500 mg L-1). Irrigation of faba bean plants with seawater levels of 3.13 and 6.25 dS m-1 led to significant reductions in shoot length, number of leaves per plant, fresh and dry weight of shoots, photosynthetic pigments, total carbohydrates, polysaccharides, nucleic acid DNA and RNA contents of faba bean leaves. Seawater salinity induced higher contents of Na+ and Cl- and decreased contents of K+, K+:Na+, Ca2+, Mg2+ and P3+. Irrigation of faba bean plant with different levels of seawater decreased seed yield and total dry weight per plant compared with those irrigated with tap water. Also, total carbohydrates and total protein contents in seeds were reduced by increased seawater salinity levels. Amino acid application as foliar spray significantly improved all the reduced parameters due to seawater stress. However, the highest level of amino acid of 1500 mg L-1 exerted the strongest effect in alleviating the harmful effect of seawater salinity stress.

La salinidad disminuye el rendimiento en zonas áridas y semiáridas. Con el aumento de la demanda de agua de riego, se están buscando fuentes alternativas. El agua de mar se consideró previamente inutilizable para irrigación debido a su salinidad. Sin embargo, esta agua puede ser utilizada con éxito en cultivos bajo ciertas condiciones. Los aminoácidos son bioestimulantes bien conocidos por sus efectos positivos sobre el crecimiento y rendimiento, y por mitigar significativamente las lesiones causadas por estrés abióticos. Por lo tanto, en el presente studio se investigó el efecto del tratamiento exógeno con aminoácidos sobre plantas de haba que crecen bajo estrés salino por irrigación con agua de mar. Se evaluó la reducción de daños por salinidad en plantas de haba mediante el uso de una mezcla de aminoácidos para mejorar los parámetros morfológicos y bioquímicos, y por lo tanto elevar el nivel de rendimiento de la planta. Se desarrolló un experimento en macetas para paliar los efectos nocivos de la salinidad del agua de mar en el haba cv. Giza 843 por aspersion foliar de una mezcla de aminoácidos con diferentes concentraciones (0, 500, 1000 o 1500 mg L-1). El riego de plantas de haba con niveles de agua de mar de 3.13 y 6.25 dS m-1 condujo a reducciones significativas en la altura de planta, número de hojas de la planta, peso fresco y seco de los brotes, y en el contenido foliar de pigmentos fotosintéticos, carbohidratos totales, polisacáridos y ácidos nucleicos (ADN y ARN). La salinidad del agua de mar indujo un mayor contenido de Na+ y Cl-, y una disminución del contenido de K+, K+: Na+, Ca2+, Mg2+ y P3+. El riego de plantas de haba con diferentes niveles de agua de mar redujo el rendimiento de semillas y el peso seco total por planta en comparación con las regadas con agua corriente. Además, el contenido de carbohidratos y proteína total en las semillas disminuyeron con el aumento de los niveles de salinidad del agua de mar. La aplicación de aminoácidos por aspersion foliar increment significativamente todos los parámetros reducidos debido al estrés por agua de mar. Sin embargo, el más alto nivel de aminoácidos (1500 mg L-1) ejerce el máximo efecto en el alivio de los efectos nocivos de estrés por salinidad del agua de mar.

Evaluation of the potential of Pistia stratiotes L. (water lettuce) for bioindication and phytoremediation of aquatic environments contaminated with arsenic

Specimens of Pistia stratiotes were subjected to five concentrations of arsenic (As) for seven days. Growth, As absorption, malondialdehyde (MDA) content, photosynthetic pigments, enzymatic activities, amino acids content and anatomical changes were assessed. Plant arsenic accumulation increased with increasing metalloid in the solution, while growth rate and photosynthetic pigment content decreased. The MDA content increased, indicating oxidative stress. Enzymatic activity and amino acids content increased at the lower doses of As, subsequently declining in the higher concentrations. Chlorosis and necrosis were observed in the leaves. Leaves showed starch accumulation and increased thickness of the mesophyll. In the root system, there was a loss and darkening of roots. Cell layers formed at the insertion points on the root stems may have been responsible for the loss of roots. These results indicate that water lettuce shows potential for bioindication and phytoremediation of As-contaminated aquatic environments.

Espécimes de Pistia stratiotes foram submetidos a cinco concentrações de arsênio (As), durante sete dias. Crescimento, absorção de As, concentração de malondialdeído (MDA), pigmentos fotossintéticos, atividades enzimáticas, concentração de aminoácidos e alterações anatômicas foram avaliadas. O acúmulo de As pelas plantas aumentou com o incremento do metaloide na solução, enquanto que a taxa de crescimento e o teor de pigmentos fotossintéticos diminuiu. O conteúdo MDA aumentou, indicando estresse oxidativo. A atividade de enzimas antioxidantes e os teores de aminoácidos aumentaram nas doses mais baixas de As, declinando nas concentrações mais elevadas. Nas folhas foram observados clorose e necrose. As folhas apresentaram acumulação de amido e aumento da espessura do mesofilo. No sistema radicular houve perda e escurecimento das raízes. Camadas de células formadas nos pontos de inserção da raiz podem ter sido responsáveis pela queda das raízes. Estes resultados indicam que a alface da água apresenta potencial para bioindicação e fitorremediação de ambientes aquáticos contaminados com As.

Evaluation of the potential of Pistia stratiotes L. (water lettuce) for bioindication and phytoremediation of aquatic environments contaminated with arsenic / Avaliação do potencial de Pistia stratiotes L. (alface d'água) para a bioindicação e fitorremediação de ambientes aquáticos contaminados com arsênio

Specimens of Pistia stratiotes were subjected to five concentrations of arsenic (As) for seven days. Growth, As absorption, malondialdehyde (MDA) content, photosynthetic pigments, enzymatic activities, amino acids content and anatomical changes were assessed. Plant arsenic accumulation increased with increasing metalloid in the solution, while growth rate and photosynthetic pigment content decreased. The MDA content increased, indicating oxidative stress. Enzymatic activity and amino acids content increased at the lower doses of As, subsequently declining in the higher concentrations. Chlorosis and necrosis were observed in the leaves. Leaves showed starch accumulation and increased thickness of the mesophyll. In the root system, there was a loss and darkening of roots. Cell layers formed at the insertion points on the root stems may have been responsible for the loss of roots. These results indicate that water lettuce shows potential for bioindication and phytoremediation of As-contaminated aquatic environments.

Espécimes de Pistia stratiotes foram submetidos a cinco concentrações de arsênio (As), durante sete dias. Crescimento, absorção de As, concentração de malondialdeído (MDA), pigmentos fotossintéticos, atividades enzimáticas, concentração de aminoácidos e alterações anatômicas foram avaliadas. O acúmulo de As pelas plantas aumentou com o incremento do metaloide na solução, enquanto que a taxa de crescimento e o teor de pigmentos fotossintéticos diminuiu. O conteúdo MDA aumentou, indicando estresse oxidativo. A atividade de enzimas antioxidantes e os teores de aminoácidos aumentaram nas doses mais baixas de As, declinando nas concentrações mais elevadas. Nas folhas foram observados clorose e necrose. As folhas apresentaram acumulação de amido e aumento da espessura do mesofilo. No sistema radicular houve perda e escurecimento das raízes. Camadas de células formadas nos pontos de inserção da raiz podem ter sido responsáveis pela queda das raízes. Estes resultados indicam que a alface da água apresenta potencial para bioindicação e fitorremediação de ambientes aquáticos contaminados com As.

Isolation of new steroids of Kala Dhaman grass (Cenchrus setigerus) and evaluation of their bioactivity

The present study was carried out to determine the possible bioactive components (steroids) of Cenchrus setigerus using GC-MS analysis and in vivo estimation of metabolites (total soluble sugar, soluble protein, proline and total phenolics), photosynthetic pigments (chlorophyll-a, chlorophyll-b and carotenoids) of seedlings and antimicrobial activity of extracts in various polar solvents from the leaves of C. setigerus. Antimicrobial activity was evaluated against three Gram-negative bacteria, including Proteusmirabilis, Klebsiella pneumonia and Agrobacterium tumefaciens andone fungus Aspergillus niger using 'disc diffusion' method, followed by the determination of minimum inhibitory concentrations (MIC) by broth dilution method. Results revealed the presence of some steroids in the isopropyl alcohol extract of C. setigerus:which are (22E)-stigmasta-4,22-dien-3-one(4.93%), δ4-sitosterol-3-one (stigmast-4-en-3-one) (4.31%), fagarsterol (lupeol) (1.25%) and ethyl iso-allocholate (0.32%). Total soluble sugars and chlorophyll-a were also recorded to be highest. The highest activity was exhibited by the isopropyl alcohol and ethyl acetate extract against P. mirabilis.

Effect of salt stress on the growth and photosynthetic pigments of pigeon pea (Cajanus cajan).

The effect of salt stress оn some physiological parameters in pigeon pea (Cajanus cajan) was studied under controlled conditions. The plants were treated with the solutions of 50 mM NaCl, 50 mM Na2So4, 100 mM NaCl and 100 mM Na2So4, starting at the appearance of first trifoliate leaf unfolded. Ground water was used for irrigation as the control. It was established that the applied doses of both salt types caused stress on the young pigeon pea plants, which found expression in the suppression of growth, photosynthetic pigment. The amount of proline in the tissues of the salt-treated plants was increased.

Physiological studies of Arachis Hypogaea L. under the influence of sulfosalicylic acid.

A study was carried out on growth, photosynthetic pigments, and yield attributing and seed characteristics of Arachis hypogaea L. (Cv. SB-11). The treatments comprised of different concentrations (5, 50, 100 and 200 ppm) of Sulfosalicylic acid (SSA). The results showed that 50 ppm concentration of foliar applied SSA effectively promoted the growth parameters, photosynthetic pigments (chl a, chl b, total chl, carotenoids and chlorophyll stability index), yield parameters and seed protein and seed oil contents of groundnut. Similarly significant decrease in severity of tikka disease was reported with 50 ppm SSA. SSA 100 ppm profound better influence on the number of branches, height of plant and the shelling percentage. It could be concluded that SSA proved to be beneficial in promoting plant growth and yield and in inducing systemic resistance against tikka disease in groundnut.

Antibacterial Activity and Phytochemical Analysis of Selected Seaweeds from Mandapam Coast, India.

Seaweeds are marine macroscopic algae which form an important component of marine living organisms.The antibacterial activity of three species of seaweeds Codiumadhaerens Anderson (green algae) Sargassum wightii Greville (brown algae) ,Acanthophora spicifera (Vahl.) Boergs (red algae) from intertidal region of the Mandapam coastal water were analysed against human pathogenic bacteria like Staphylococcus aureus, Vibrio cholerae, Shigelladysentriae, Shigellabodii, Salmonella paratyphi, Pseudomonas aeuroginosa and Klebsiella pneumoniae. The present study was also carried out to investigate the phytochemical constituents like alkaloids, flavanoids, phenols, proteins and free amino acids, saponins, sterols, terpenoids and Sugars in all samples and coumarin and glycosides, quinones and tannin, estimation of biochemical composition (protein, sugar, lipid), photosynthetic pigments like chlorophyll, carotenoid and mineral composition. The results indicated that the maximum protein content (6.396±0.97%) was recorded in the brown alga S. wightii. The maximum carbohydrate content (6.29±0.063%) was recorded in the red alga A. spicifera. The maximum lipid content (1.213±0.02%) was recorded in green alga C.adharens. The highest total phenol (216.65±17.38) and flavanoid (379.99±21.813) was in the brown seaweed S. wightii. The maximum chlorophyll ‘a’ (0.347±0.051), total chlorophyll (0.438±0.061) and carotenoid (0.670±0.225) were recorded in the brown seaweed S. wightii where as chlorophyll ‘b’ (0.107±0.016) was highest in C. adharens. Among the 14 minerals analyzed most of them were highest in the red alga A. spicifera. Among the three seaweeds screened for their antibacterial activity the brown alga S. wihgtii is more superior to the red alga A. spicefera and green alga C.adharens in controlling the growth of most of the pathogens tested. The highest zone of inhibition (13mm) was recorded in methanol extract of the red alga against Vibrio cholerae.

A study of chlorophyll-like and phycobilin pigments in the C endosymbiont of the apple- snail Pomacea canaliculata

Pigments present in the brown-greenish C morph of an intracellular endosymbiont of Pomacea canaliculata were investigated. Acetone extracts of the endosymbiotic corpuscles showed an absorption spectrum similar to that of chlorophylls. Three fractions obtained from silica gel column chromatography of the acetone extracts (C I, C II and C III), were studied by positive ion fast atom bombardment-mass spectrometry (FAB-MS) and hydrogen-nuclear magnetic resonance (H-NMR). Results indicated the presence of (1) a sterol in the yellow colored C I fraction; (2) a mixture of pheophorbides a and b in the major green fraction, C II; and (3) a modified pheophorbide a in the smaller green fraction, C III. Aqueous extracts of the C endosymbiont did not show evidence of the occurrence of C-phycocyanin, allophycocyanin or phycoerithrin (light absorption, fluorescence emission, and electrophoresis of the protein moieties) while cyanobacterial cells (Nostoc sp.) showed evidence of C-phycocyanin and allophycocyanin. The possible phylogenetic and functional significance of the pigments present in the C endosymbiont is discussed.

Growth, photosynthetic activity and oxidative stress in wheat (Triticum aestivum) after exposure of lead to soil.

The present study was conducted to assess quantitative information about lead (Pb) contamination in soil on the growth and physiology of wheat. Solutions with three different concentrations of Pb as [Pb(NO3)2 at 500, 1000 and 2500 >M] were incorporated into the soil to achieve Pb-stressed conditions in comparison to unstressed, water treated, control variant. Wheat growth measured in terms of root length, shoot length and dry weight exhibited a significant decline with increasing Pb concentrations in the soil. Root and shoot length and seedling weight declined in the range of ~23–51, ~17–44, and ~21–44% in response to 500 to 2500 >M Pb. In addition, there was a significant reduction in the levels of photosynthetic pigments-chlorophyll a (16-66%) and b (10-24%) and total chlorophyll content (by 14-39%) in plants growing in Pb-contaminated soil. It indicated a negative effect on photosynthetic activity in wheat and was confirmed by reduced photochemical efficiency of PSII (Fv/Fm) in the range of ~ 3-37% in response to 500 to 2500 >M Pb. The reduction in wheat growth in Pb-contaminated soil was accompanied by induction of oxidative stress as indicated by enhanced lipid peroxidation in terms of malondialdehyde (MDA) content (by 18-40%) and hydrogen peroxide (H2O2) content (by 34-123%) and alterations in the activity of enzymes, superoxide dismutases (SOD) and guaiacol peroxidases (GPX) in wheat roots. The study concludes that Pb in soil inhibits growth and phototsynthetic activity in wheat through induction of oxidative stress.

Influence of light intensity on growth and physiological characteristics of common sage (Salvia officinalis L.)

The aim of this work was to investigate the effects of four different light intensities on the growth characteristics, physiological parameters and leaf photosynthetic pigments of Salvia officinalis L. The plant's dry mass, number of the leaves and physiological parameters indicated a strong positive correlation with the light intensity. On the other hand, the plant's height and leaf photosynthetic pigments were increased at low light treated plants. These results suggest that the aromatic herb Salvia officinalis L. is adaptable to different light environments.

Structural and ecophysiological alterations of the water hyacinth [Eichhornia crassipes (Mart.) Solms] due to anthropogenic stress in Brazilian rivers

In this work, the structural and ecophysiological alterations (chlorophyll a fluorescence and photosynthetic pigments), and quantification of Cr, Pb and Zn in the leaf limb, petiole and younger and older roots of water hyacinth from the lower, medium and upper Paraíba do Sul river (PSR) and Imbé river were evaluated. The plants from the medium and upper PSR (more industrialized and populated regions) exhibited lower turgid cell in the root cortex, less root hairs and leaf epidermis, chloroplasts with plastoglobules and increased stroma volume. Higher concentrations of metals were observed in the younger and older roots from the medium PSR plants. The results suggested that the plants from more anthropized regions were able to maintain the maximum quantum yield (Fv/Fm) which was a result from the metabolic fitting, increasing the non-photochemical quenching, reducing total chlorophyll/carotenoids and leading to the structural modifications.

Crescimento de Hymenaea courbaril L. var. stilbocarpa (Hayne) Lee et Lang. e Enterolobium contortisiliquum (Vell) Morong (Leguminosae) sob diferentes níveis de sombreamento / Growth of Hymenaea courbaril L. var. stilbocarpa (Hayne) Lee et Lang. e Enterolobium contortisiliquum (Vell) Morong (Leguminosae) under different shading levels

Hymenaea courbaril L. var. stilbocarpa (Hayne) Lee et Lang. é uma espécie clímax tolerante a sombra, ao passo que Enterolobium contortisiliquum (Vell.) Morong. é uma espécie pioneira. O desenvolvimento destas espécies pode refletir a habilidade de adaptação aos diferentes fatores ambientais (luz, água e temperatura) no local em que estão crescendo. O suprimento inadequado de um desses fatores pode reduzir o vigor da planta e limitar seu desenvolvimento. O presente trabalho teve como objetivo avaliar os efeitos do nível de sombreamento no crescimento e a concentração de pigmentos fotossintéticos em duas espécies de leguminosas arbóreas, Hymenaea courbaril L. var. stilbocarpa (Hayne) Lee et Lang. e Enterolobium contortisiliquum (Vell.) Morong. O experimento foi conduzido no Setor de Olericultura do Centro Universitário Luterano de Ji-Paraná (CEULJI/ULBRA)/Rondônia. Durante a formação das mudas, ambas as espécies foram expostas a quatro tratamentos de sombra: 0 % (controle - sol pleno); 30 %; 50 % e 80 %. Cada tratamento foi constituído com três repetições de cada espécie; o delineamento experimental foi inteiramente casualisado. Quatro meses após a semeadura, as seguintes análises foram realizadas: número de folhas, altura da planta, comprimento do sistema radicular, massa seca total e concentração de pigmentos fotossintéticos. O tratamento sob sol pleno afetou negativamente o crescimento de ambas as espécies. As mudas crescidas sob 50% e 80% apresentaram melhor desenvolvimento. Conforme o aumento do sombreamento houve um decréscimo na razão clorofila a/b e um aumento nas concentrações de clorofila total e carotenóides totais.

Hymenaea courbaril L. var. stilbocarpa (Hayne) Lee et Lang. is a clímax shadow tolerant specie and Enterolobium contortisiliquum (Vell.) Morong., by the other hand, is considered as a pioneer specie. The development of these species may reflect its adaptation ability to different environmental elements (light, water and temperature) at its growth site. An inadequate supply of some of these elements may reduce plant vigor and limit its development. This work aimed to evaluate the effects of shade intensity on the growth and photosynthetic pigment concentration of two arboreal legumes that are typical to northern Brazil, namely, the Hymenaea courbaril L. var. stilbocarpa (Hayne) Lee et Lang. and the Enterolobium contortisiliquum (Vell.) Morong. The experiment was carried out at the Centro Universitário Luterano de Ji-Paraná (CEULJ/ULBRA)/Rondônia. During the formation of the seedlings, both species were exposed to four treatments of shade: 0 % (control - without shade); 30 %; 50 % e 80 %. Each treatment was carried out with three replications for each species; the experimental design was completely randomized. Four month after sowing, the following analyses were carried out: number of leaves, plant height, roots length, dry mass and photosynthetic pigment concentration. The treatment under 0% shade impaired the seedling growth of both species. The most favorable treatments were 50 % and 80 % shade. According to the shade intensity, the chlorophyll a/b ratio decreased and the chlorophyll and carotenoids increased.

Air pollution induced changes in the photosynthetic pigments of selected plant species.

Changes in the concentration of different photosynthetic pigments (Chlorophyll and carotenoids) were determined in the leaves of six tree species exposed to air pollution due to vehicular emissions. The six tree species, which are all economically important because of their being fruit bearers, used for timber, fodder and as road side trees on the basis of their air pollution tolerance index. These included Mangifera indica L., Tectona grandis Linn.f., Shorea robusta Gaertn.f., Holoptelea integrifolia (Roxb.) Planch, Eucalyptus citridora Hook. Syn. and Mallotus philippinensis Muell-Arg. Reduction in chlorophyll ‘a’, ‘b’ and carotenoid was recorded in the leaf samples collected from polluted areas when compared with samples from control areas. The highest reduction in total chlorophyll was observed in Holoptelea integrifolia (Roxb.) (48.73%) Planch whereas, the lowest reduction (17.84 %) was recorded in Mallotus philippinensis Muell-Arg. Similarly in case of carotenoid contents, highest reduction (43.02 %) was observed in Eucalyptus citridora, and lowest in Mallotus philippinensis Muell-Arg (19.31 %). The data obtained were further analyzed using one-way ANOVA and a significant change was recorded in the studied parameters. These studies clearly indicate that the vehicular induced air pollution reduces the concentration of photosynthetic pigments in the trees exposed to road side pollution.