Microencapsulated Caraway Essential Oil Affects Initial Growth of Maize Cultivars

Caraway (Carum carvi L.) essential oil is a candidate for botanical herbicides. A hypothesis was formulated that the sand-applied maltodextrin-coated caraway oil (MCEO) does not affect the growth of maize (Zea mays L.). In the pot experiment, pre-emergence application of five doses of MCEO was tested on four maize cultivars up to the three-leaf growth stage. The morphological analyses were supported by the measurements of relative chlorophyll content (SPAD), two parameters of chlorophyll a fluorescence, e.g., Fv/Fm and Fv/F0, and fluorescence emission spectra. The analyzed MCEO contained 6.5% caraway EO with carvone and limonene as the main compounds, constituting 95% of the oil. The MCEO caused 7-day delays in maize emergence from the dose of 0.9 g per pot (equal to 96 g m−2). Maize development at the three-leaf growth stage, i.e., length of roots, length of leaves, and biomass of shoots and leaves, was significantly impaired already at the lowest dose of MCEO: 0.4 g per pot, equal to 44 g m−2. A significant drop of both chlorophyll a fluorescence parameters was noted, on average, from the dose of 0.7 g per pot, equal to 69 g m−2. Among the tested cultivars, cv. Rywal and Pomerania were less susceptible to the MCEO compared to the cv. Kurant and Podole. In summary, maize is susceptible to the pre-emergence, sand-applied MCEO from the dose of 44 g m−2.

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Photochemical activity of primary leaves in cadmium stressed Phaseolus coccineus depends on their growth stages

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1995.036 ◽

2014 ◽

Vol 64 (3) ◽

pp. 273-279 ◽

Cited By ~ 25

Author(s):

Ewa Skórzyńska-Polit ◽

Tadeusz Baszyński

Keyword(s):

Chlorophyll A ◽

Chlorophyll A Fluorescence ◽

Growth Stage ◽

Growth Parameters ◽

Phaseolus Coccineus ◽

Growth Stages ◽

Initial Growth ◽

Acceptor Side ◽

Runner Bean ◽

Bean Plants

Runner bean plants (Phaseolus coccineus L., cv. Piękny Jaś) grown hydroponically were treated with Cd (2.5 • 10-5 M Cd in the form of 3CdSO4 • 8H2O) at different stages of primary leaves development. Ten days after the metal treatment, the changes in leaf growth parameters and their PSII photochemistry were investigated. The younger were the plants exposed to Cd (at the initial growth stage of primary leaves) the stronger was the leaf area reduction, fresh weight decrease and increase of plastid pigment level. These changes were correlated with lower level of photosynthetic 02 evolution (75% of control) but chlorophyll a fluorescence measurements suggested an inhibitory effect of Cd on the acceptor side of PSII. With the development of primary leaves the sensitivity of plants to Cd increased. Cd treatment of plants at the final growth stage of the primary leaves caused slight changes in growth parameters compared with control, whereas the chlorophyll content and PSII activity (48% of control) significantly decreased. Analyses of fast chlorophyll a fluorescence kinetics revealed changes suggesting Cd-induced alterations of PSII complex extending on to their acceptor side and the reaction centre. Differential response of primary leaves to Cd depending on their growth stages indicated alterations of the adaptation mechanism in leaf cells of runner bean plants. The decrease in younger Cd-treated plants of photosynthetic activity was connected with disturbances in growth processes, however in plants treated with Cd at the final growth stage of the primary leaves it was resulted from destruction of the photosynthetic apparatus.

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SENSITIVITY TO ENVIRONMENTAL STRESS OF PRATA,JAPIRA AND VITÓRIA BANANA CULTIVARS PROVEN BY CHLOROPHYLL a FLUORESCENCE

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452017991 ◽

2017 ◽

Vol 39 (2) ◽

Author(s):

PRISCILA NOBRES DOS SANTOS ◽

DIOLINA MOURA SILVA ◽

CAMILLA ZANOTTI GALLON ◽

JOSÉ AIRES VENTURA

Keyword(s):

Environmental Stress ◽

Chlorophyll A ◽

Chlorophyll A Fluorescence ◽

Physiological Responses ◽

Fluorescence Emission ◽

Conservation Of Energy ◽

Post Harvest ◽

Mda Content ◽

Two Stages

ABSTRACT This study aimed to evaluate the physiological responses to environmental stress during pre- and post-harvest of the following banana cultivars: Prata (AAB), Japira (AAAB) and Vitoria (AAAB). Analyses were carried out on young plants at vegetative stage (daughter-plant) and adult plants at reproductive stage (motherplant). The experimental design was completely randomized. In the in vivo pre-harvest analysis were used seven replications, in a factorial scheme (3x2x2), three cultivars and two stages (vegetative and reproductive) and two collection periods (March and June). For the analysis of post-harvest quality were used five replications in a factorial design (3x2x5), corresponding to three cultivars, two development stages and five periods of post-harvest analysis, carried out every two days from stage 4 of fruit ripening. The chlorophyll a fluorescence emission kinetics showed low photochemical performance of the three cultivars in June, a period characterized by lower temperatures and water deficit. Prata was the cultivar with the lowest tolerance to abiotic physiological behavior changes, which also reflected in fruit quality, because there was a change in physical and physicochemical parameters. Japira and Vitoria cultivars showed similar physiological responses in the pre- and post-harvest periods, according to their phylogenetic proximity. The total performance index, i.e., the conservation of energy absorbed by PSII up to the reduction of the final PSI acceptors (PItotal) and the di-malonic aldehyde (MDA) content were significantly higher in Japira and Vitoria cultivars compared to Prata cultivar in the reproductive phase. There was no significant change in the potential quantum efficiency of PSII (FV / FM = jP0) among the three cultivars. It was concluded that Japira and Vitoria cultivars showed greater plasticity to tolerate or even adapt to abiotic variations keeping higher fruit yield. PItotal is the most sensitive parameter during the banana life cycle and important tool for distinguishing different cultivars yields.

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Stability of Chlorophyll a Monomer Incorporated into Cremophor EL Nano-Micelles under Dark and Moderate Light Conditions

Molecules ◽

10.3390/molecules25215059 ◽

2020 ◽

Vol 25 (21) ◽

pp. 5059

Author(s):

Ewa Janik-Zabrotowicz ◽

Marta Arczewska ◽

Patrycja Prochniewicz ◽

Izabela Świetlicka ◽

Konrad Terpiłowski

Keyword(s):

Chlorophyll A ◽

Self Assembly ◽

Molecular Spectroscopy ◽

Fluorescence Emission ◽

Molecular Organization ◽

Cremophor El ◽

Light Conditions ◽

Fluorescence Emission Spectra ◽

Pigment Stability ◽

The Stability

In this paper, stability of chlorophyll a monomers encapsulated into the Cremophor EL nano-micelles was studied under dark and moderate light conditions, typical of a room with natural or artificial lighting, in the presence of oxygen. The pigment stability against visible light was determined using the dynamic light scattering and molecular spectroscopy (UV-Vis absorption and stationary fluorescence) methods. Chlorophyll a, at the molar concentration of 10−5 M, was dissolved in the 5 wt% Cremophor emulsion for comparison in the ethanolic solution. The stability of such a self-assembly pigment–detergent nano-system is important in the light of its application on the commercial-scale. The presented results indicate the high stability of the pigment monomeric molecular organization in the nano-emulsion. During the storage in the dark, the half-lifetime was calculated as about 7 months. Additionally, based on the shape of absorption and fluorescence emission spectra, chlorophyll aggregation in the Cremophor EL aqueous solution along with the time was excluded. Moreover, the average size of detergent micelles as chlorophyll carriers was not affected after 70 days of the nano-system storage. Pigment stability against the moderate white light (0.1 mW) did not differ significantly from storage conditions in the dark. The photooxidation products, detected by occurrence of new absorption and fluorescence emission bands, was estimated on the negligible level. The stability of such a self-assembly pigment–detergent nano-system would potentially broaden the field of chlorophyll a (chl a) application in the food industry, medicine or artificial photosynthesis models.

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