scholarly journals α-Tocopherol Protection Against Drought-Induced Damage In Rosmarinus Officinalis L. And Melissa Officinalis L.

1999 ◽  
Vol 54 (9-10) ◽  
pp. 698-703 ◽  
Author(s):  
Sergi Munné-Bosch ◽  
Karin Schwarz ◽  
Leonor Alegre
Keyword(s):  
Chlorophyll Content ◽  
Fluorescence Yield ◽  
Tocopherol Content ◽  
Rosmarinus Officinalis ◽  
Photochemical Quenching ◽  
Severe Drought ◽  
Melissa Officinalis ◽  
Psii Photochemistry ◽  
Drought Conditions ◽  
Rosmarinus Officinalis L

Summer diurnal variations of photosynthesis and α-tocopherol content were measured in relation to natural drought in field-grown rosemary (Rosmarinus officinalis L.) and lemon balm (Melissa officinalis L.) plants. During the summer relative water contents (RWC) of ca. 40% in Rosmarinus officinalis and ca. 30% in Melissa officinalis were attained, indicating severe drought. Both species showed similar diurnal patterns of net CO2 assimilation rates (A) with a wide plateau of maximum photosynthesis at midday in the absence of drought and one peak of maximum photosynthesis early in the morning under drought conditions. Net CO2 assimilation rates decreased by ca. 75% due to drought in both species. Melissa officinalis plants showed a significant decrease in the relative quantum efficiency of PSII photochemistry (ΦPSII), ratio of variable to maximum fluorescence yield (Fv/Fm) and chlorophyll content of leaves by ca. 25% under drought conditions at midday. In contrast, ΦPSII, Fv/Fm and chlorophyll content remained constant throughout the experiment in R. officinalis plants. Although the non-photochemical quenching of chlorophyll fluorescence increased from ca. 1.8 to 3 and the a-tocopherol content rose fifteen fold in both species in response to drought, only R. officinalis plants were able to avoid oxidative damage under drought conditions by the joint increase of carotenoids and α-tocopherol

scholarly journals Chlorophyll α Fluorescence Parameters as an Indicator to Identify Drought Susceptibility in Common Bush Bean

Agronomy ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 526 ◽  
Author(s):  
Alefsi David Sánchez-Reinoso ◽  
Gustavo Adolfo Ligarreto-Moreno ◽  
Hermann Restrepo-Díaz
Keyword(s):  
Water Deficit ◽  
Block Design ◽  
Reproductive Stage ◽  
Vegetative Stage ◽  
Initial Slope ◽  
Maximum Efficiency ◽  
Photochemical Quenching ◽  
Psii Photochemistry ◽  
Drought Conditions ◽  
Bush Bean

The common bean is susceptible to drought conditions and the evaluation of plant responses to low water availability can be difficult. The quantification of chlorophyll fluorescence as a sensitive trait to environmental stresses is an important alternative in the characterization of drought-susceptible genotypes. The objective of this study was to evaluate mainly the use of chlorophyll α fluorescence (maximum efficiency of PSII (Fv/Fm), photochemical quenching (qP), non-photochemical quenching (NPQ)) and rapid light-response curves (RLCs) (initial slope of the curve (α), minimum saturation irradiance (Ik) and maximum relative electron transport rate (ETRmax)) parameters as tools for the identification of susceptible or tolerant bush bean cultivars to water deficit stress conditions in two different phenological stages. Using a randomized block design in a factorial arrangement, five bush bean cultivars (Cerinza, Bachue, NUA35, Bacata and Bianca) were evaluated under water deficit conditions by the suspension of irrigation for 15 days from 40 to 55 Days after Emergence (DAE) (vegetative stage) or 50 to 65 DAE (reproductive stage). The results showed that Fv/Fm and NPQ recorded the highest variation due to water deficit conditions, especially in the vegetative stage. The greatest reductions in Fv/Fm (0.67) and NPQ (0.71) were evidenced in cultivar NUA35 compared to its control plants (0.78 and 1.07, respectively). The parameters obtained from RLCs showed that cultivar Bacata registered the lowest α (0.17) and Ik (838.19 μmol∙m−2∙s−1) values compared to its control plants (α 0.23; Ik 769.99 μmol∙m−2∙s−1). Differences were only obtained in ETRmax in the reproductive stage (50–65 DAE) in which cultivar NUA35 reached values of 158.5 in stressed plants compared to control plants (251.22). In conclusion, the parameters derived from RLCs such as α and Ik can be used as tools to identify drought susceptibility in the vegetative stage, whereas ETRmax can be used in the reproductive stage. In addition, PSII photochemistry (Fv/Fm and NPQ) can also help to understand the agronomic responses of common bush bean cultivars to drought conditions.

PSII Photochemistry and Antioxidant Responses of a Chickpea Variety Exposed to Drought

2008 ◽  
Vol 63 (7-8) ◽  
pp. 583-594 ◽  
Author(s):  
Tuǧçe Kalefetoǧlu Macar ◽  
Yasemin Ekmekçi
Keyword(s):  
Vegetative Stage ◽  
Carotenoid Content ◽  
Photochemical Quenching ◽  
Severe Drought ◽  
Anthocyanin Content ◽  
Sod Activity ◽  
Leaf Production ◽  
Total Carotenoid Content ◽  
Fluorescence Characteristics ◽  
Psii Photochemistry

The effect of drought on the chickpea variety ILC 3279 was investigated at the vegetative stage. After 20 days from sowing, the plants subjected to drought stress for 3, 5 and 7 days imposed by withholding water were permitted to recover by rewatering for 2 days after 3, 5 and 7 days of drought. Shoot elongation, leaf production, fresh and dry biomass reduced while MDA and proline accumulation increased with extended duration of stress. The plants stressed for 3 days exhibited a rapid drop in their relative and absolute water contents. The quantum efficiency of PSII open centres in the dark-adapted and light-saturated state, excitation energy trapping of PSII and electron transport rate decreased significantly from the 5th day to the end of the drought treatments. Plants drought-stressed for 7 days brought about a marked increase in non-photochemical energy dissipation and a marked decline in photochemical quenching. After rewatering all chlorophyll a fluorescence characteristics except for FM completely recovered and reached the control values. Under 5 and 7 days of drought, the anthocyanin content increased gradually while the total chlorophyll content of leaves declined compared to the controls. The total carotenoid content remained unchanged during the experiments. The antioxidant enzyme response to drought treatments was quite variable. The total SOD activity upregulated with increasing duration of stress. On the other hand, the total APX activity was significantly higher only on the 7th day while the total POD activity increased from the 5th day. Differences in the total GR activity of treated groups were not statistically significant compared to their controls throughout the treatments. The present results indicate that the chickpea variety ILC 3279 withstands severe drought with its upregulated protective mechanisms at the vegetative stage.

FORMULADO DE ALECRIM NO CONTROLE DE ANTRACNOSE E CONSERVAÇÃO EM PÓS-COLHEITA DE BANANA NANICÃO

2019 ◽  
Vol 2 (2) ◽  
pp. 16
Author(s):  
Eloisa Lorenzetti ◽  
Dablieny Hellen Garcia Souza ◽  
Juliano Tartaro ◽  
José Renato Stangarlin ◽  
Gilberto Costa Braga
Keyword(s):  
Rosmarinus Officinalis ◽  
Rosmarinus Officinalis L ◽  
Colletotrichum Musae

A banana apresenta elevada suscetibilidade a doenças como as podridões que diminuem o tempo de prateleira do fruto. Uma das formas de controlar as doenças seria a utilização de métodos alternativos como os extratos de plantas medicinais. Assim, o objetivo deste estudo foi verificar a ação de formulados de alecrim (Rosmarinus officinalis L.) pó e líquido no controle de antracnose causada pelo fungo Colletotrichum musae (Berk & Curt.) Von Arx. e na maturação de banana ‘Nanicão’ em pós-colheita. Foram utilizadas as concentrações 0%; 0,25%; 0,5%; 1%; 1,5% e 2% do pó solúvel de extrato de alecrim diluído em água destilada, e as concentrações 0%; 0,5%; 1%; 2%; 4% e 6% do formulado aquoso contendo 21% de resíduo seco de alecrim diluído em água destilada. Foi realizada a mensuração da área de cada fruto e avaliada a severidade e a maturação a partir de porcentagem de área dos frutos, sendo os resultados utilizados para calcular a área abaixo da curva de progresso da doença (AACPD) e a porcentagem de maturação dos frutos. Realizou-se analise de regressão a partir dos dados obtidos e pode-se verificar que para o formulado de alecrim em pó a AACPD reduziu mais de 29% e para a maturação a redução foi de 21,72%. Para o formulado líquido a redução foi de 14,31% para AACPD e cerca de 10% para maturação. Assim, concluiu-se que houve eficiência por parte dos formulados de alecrim no controle da antracnose e no aumento da vida de prateleira da banana ‘Nanicão’.

PROTECTIVE EFFECT OF ROSEMARY (ROSMARINUS OFFICINALIS L.) EXTRACT OVER THE GENOTOXICITY INDUCED BY CYCLOPHOSPHAMIDE IN SWISS ALBINO MICE

2016 ◽  
Vol 72 (9) ◽  
Author(s):  
Dr. Ayman Salah El-Seedy ◽  
Hany George Shalaby ◽  
Mohamed Ahmed El-Sehrigy ◽  
Madiha Mohiy El-Dein Ghoneim
Keyword(s):  
Protective Effect ◽  
Rosmarinus Officinalis ◽  
Swiss Albino Mice ◽  
Albino Mice ◽  
Rosmarinus Officinalis L
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