Enhanced Uv-B Radiation Alleviates the Adverse-Effects of Summer Drought in 2 Mediterranean Pines under Field Conditions
Φόρτωση...
Ημερομηνία
Συγγραφείς
Petropoulou, Y.
Kyparissis, A.
Nikolopoulos, D.
Manetas, Y.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Physiologia Plantarum
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
The effects of enhanced UV-B (290-320 nm) radiation on two native Mediterranean pines (Pinus pinea L., Pinus halepensis Mill.) were recorded during a one-year field study. Plants received ambient or ambient plus supplemental UV-B radiation (simulating a 15% stratospheric ozone depletion over Patras, Greece, 35.3 degrees N, 29.1 degrees E) and only natural precipitation, i.e. they were simultaneously exposed to other natural stresses, particularly water stress during summer. Supplemental UV-B irradiation started in early February, 1993 and up to late June, no effects were observed on growth and photochemical efficiency of photosystem II, as measured by chlorophyll fluorescence induction. Water stress during the summer was manifested in the control plants as a decline in the ratio of variable to maximum fluorescence (F-v/F-m), the apparent photon yield for oxygen evolution (Phi(i)) and the photosynthetic capacity at 5% CO2 (P-m). In addition, a partial needle loss was evident. Under supplemental UV-B radiation, however, the decreases in F-v/F-m, Phi(i), and P-m, as well as needle losses were significantly less. Soon after the first heavy autumn rains, photosynthetic parameters in both control and W-B treated plants recovered to similar values, but the transient summer superiority of W-B irradiated plants resulted in a significant increase in their dry weight measured at plant harvest, during late January, 1994. Plant height, UV-B absorbing compounds, photosynthetic pigments and relative water content measured at late spring, late summer and at plant harvest, were not significantly affected by supplemental UV-B radiation. The results indicate that enhanced W-B radiation may be beneficial for Mediterranean pines through a partial alleviation of the adverse effects of summer drought.
Περιγραφή
Λέξεις-κλειδιά
biomass, mediterranean pines, ozone depletion, photosynthesis, pinus halepensis, pinus pinea, uv-b radiation, water stress, mild water-stress, ultraviolet-radiation, loblolly-pine, higher-plants, growth, irradiation, light, responses, seedlings, quality
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://A1995QY43100006
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Επιστημών και Τεχνολογιών. Τμήμα Βιολογικών Εφαρμογών και Τεχνολογιών