Comparison of susceptibility of leaves on short-term UV-B irradiation

Abstract

) at light on cucumber and peppermint leaves were studied. A considerable decrease of the most important chlorophyll fluorescence parameters values mainly in the cucumber leaves, compared to the control, was observed. It indicates damages as well as at a donor and acceptor side of photosystem II, specially in the oxygen evolving complex, electron transport and connected with the dark reactions. In the peppermint leaves these values were unchanged or slight decreased. After 24 h from disappearing of the applied UV-B stress, adverse changes became established, especially in the cucumber leaves show irreversible damages of photosystem II. Coefficient of nonphotochemical quenching increased by 50% in the peppermint leaves, while in cucumber remained unchanged. Chlorophyll delayed luminescence coefficient was decreased by 36% in the UV-B irradiated cucumber leaves and by 25% in the peppermint leaves. Content of ultraviolet-absorbing compounds was higher in peppermint leaves by 78% than in the cucumber. Generally, peppermint seemed to be more tolerant to the applied UV-B radiation compared to cucumber. K e y w o r d s: ultraviolet-B, leaves, cucumber, peppermint, photosynthesis reactions

Impact of a Longwave UV-B Radiation on Soybean Plants Grown at Increased Nickel Concentration in Soil

“…The peroxidase (PRX) and catalase (CAT) activity were analysed as described Skórska (2000), using a Specord UV-VIS M 42 spectrophotometer. Chlorophyll fluorescence measured by means of a portable PAM-200 Chlorophyll Fluorometer (Heinz Walz GmbH, Germany) was described by Skórska and Murkowski (2012). The results were presented as means (5-10 biological independent repetitions) ± standard deviation, excluding fresh and dry mass, which was determined for all 10 plants, and divided per one plant.…”

Acta Biologica Cracoviensia s. Botanica

“…A single sample was 100 cm 3 of suspension in a glass, and one series -six samples. All 24 samples were divided into four groups, one of which was the control, and three others were subjected to UV-B irradiation with the broadband lamp VL-115 M (emission spectrum presented by Skórska and Murkowski, 2012) for 20, 40 and 80 minutes respectively, and the equivalent values of UV-B doses were 3.2, 6.4 and 12.8 kJ m -2 . The measurements of UVB radiation were performed using an IL 1403 radiometer with a SEL 240-UVB1 calibrated detector (International Light Inc., USA).…”