Effects of Acclimatization Temperatures on Antioxidant Enzyme Activities in Mericlones of a Cattleya Hybrid
Year: 2004
Type: article
Abstract: Mericlones of Brassolaeliocattleya Shinmei 'Sanyang' transplanted from flasks to pots with sphagnum moss were acclimated for 4 weeks in growth cabinets controlled at 15°C, 25°C and 35°C under 50 μmol · m-2 · s-1 for 16-hr photoperiod with fluorescent lamps. Except for root CAT activity that increased at 25°C, superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT) activities in leaves and roots fluctuated slightly. However, those activities at 15°C and 35°C, initially changed significantly after the onset of the treatments; they became stable during the rest of the acclimation period. Based on the antioxidative enzyme activities, the responses to thermal stress were greater in roots than in leaves. These results indicate the significance of managing the root environment at transplantation time. SOD activities that were highest at 35°C, followed by those at 15°C, clearly demonstrate the effects of acclimation temperatures (thermal stress ) on both leaves and roots. Thermal effects on APX and CAT differed between leaves and roots. SOD activities in both leaves and roots as affected by the high temperature became smoothly stabilized. CAT activated for 48 hrs after the onset of the acclimation treatment reverted to its initial level and remained so for several more weeks. Activities in SOD, APX, and CAT in roots that increased at 15°C indicate that cattleya plants are heat-but not cold-resistant.
DOI: 10.2503/jjshs.73.386
Authors: Youhong Li, Ken Imai, Hajime Ohno, Shuichiro Matsui
Language: English
Subfield: Plant Science
Domain: Life Sciences
Open Access status: diamond
OpenAlex ID: W2086972209