Photosynthesis, respiration and antioxidant enzymes in pepper leaves under drought and heat stresses

• Published in: Biologia plantarum Vol. 54; no. 4; pp. 761 - 765
• Main Authors: Hu, W.H.,Jinggangshan Univ., Ji'an (China). Dept. of Life Science, Xiao, Y.A.,Jinggangshan Univ., Ji'an (China). Dept. of Life Science, Zeng, J.J.,Jinggangshan Univ., Ji'an (China). Dept. of Life Science, Hu, X.H.,Jinggangshan Univ., Ji'an (China). Dept. of Life Science
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.12.2010; Institute of Experimental Botany of the Czech Academy of Sciences
• Subjects: ACTIVIDAD ENZIMATICA; ACTIVITE ENZYMATIQUE; alternative oxidase; ANTIOXIDANTES; ANTIOXIDANTS; ANTIOXYDANT; ascorbate peroxidase; Biomedical and Life Sciences; Brief Communication; CAPSICUM ANNUUM; chlorophyll fluorescence; CHLOROPHYLLE; CHLOROPHYLLS; CITOCROMOS; CLOROFILAS; CYTOCHROME; CYTOCHROMES; DROUGHT RESISTANCE; DROUGHT STRESS; drought tolerance; ECHANGE GAZEUX; ENZYME ACTIVITY; ESTRES DE SEQUIA; ESTRES TERMICO; FEUILLE; FLUORESCENCE; FLUORESCENCIA; FOTOSINTESIS; GAS EXCHANGE; HEAT STRESS; HEAT TOLERANCE; HOJAS; http://www.fao.org/aos/agrovoc#c_10935; http://www.fao.org/aos/agrovoc#c_11098; http://www.fao.org/aos/agrovoc#c_11486; http://www.fao.org/aos/agrovoc#c_11488; http://www.fao.org/aos/agrovoc#c_1288; http://www.fao.org/aos/agrovoc#c_13251; http://www.fao.org/aos/agrovoc#c_1577; http://www.fao.org/aos/agrovoc#c_2392; http://www.fao.org/aos/agrovoc#c_24091; http://www.fao.org/aos/agrovoc#c_24993; http://www.fao.org/aos/agrovoc#c_2604; http://www.fao.org/aos/agrovoc#c_27497; http://www.fao.org/aos/agrovoc#c_3725; http://www.fao.org/aos/agrovoc#c_4243; http://www.fao.org/aos/agrovoc#c_511; http://www.fao.org/aos/agrovoc#c_5474; http://www.fao.org/aos/agrovoc#c_5812; http://www.fao.org/aos/agrovoc#c_9421; HYDROGEN PEROXIDE; INTERCAMBIO DE GASES; LEAVES; Life Sciences; net photosynthetic rate; OXIDOREDUCTASES; OXIDORREDUCTASAS; OXYDOREDUCTASE; PEROXIDASAS; PEROXIDASES; PEROXIDO DE HIDROGENO; PEROXYDASE; PEROXYDE D'HYDROGENE; photorespiration rate; PHOTOSYNTHESE; PHOTOSYNTHESIS; Plant Sciences; RESISTANCE A LA SECHERESSE; RESISTENCIA A LA SEQUIA; RESPIRACION; RESPIRATION; STRESS DU A LA SECHERESSE; STRESS THERMIQUE; SUPEROXIDE DISMUTASE; SUPEROXIDO DISMUTASA; SUPEROXYDE DISMUTASE; TOLERANCE A LA CHALEUR; TOLERANCIA AL CALOR; net photosynthetic rate; ascorbate peroxidase; chlorophyll fluorescence; superoxide dismutase; drought tolerance; photorespiration rate; alternative oxidase
• ISSN: 0006-3134; 1573-8264
• DOI: 10.1007/s10535-010-0137-5

Leaf gas exchange, chlorophyll fluorescence and activities of antioxidant enzymes were studied in two Capsicum annuum cultivars grown under drought (D) and heat (H), as well as under drought and heat in combination (HD). The drought-tolerant cv. Zhengjiao 13 exhibited greater net photosynthetic rate (PN) and cytochrome respiratory pathway activity (RSHAM), and lower contents of superoxide radical and hydrogen peroxide than the drought-sensitive cv. Longkouzaojiao. The PN and RSHAM decreased and ROS production increased under D and HD in both cultivars. As compared to the Longkouzaojiao, Zhengjiao 13 retained higher non-photochemical quenching (NPQ), photorespiration rate (RL), and alternative respiratory pathways (RKCN) under D and HD. In both cultivars, drought increased the superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities in the cytosol, chloroplasts and mitochondria. Although SOD and APX activities decreased in Longkouzaojiao under HD, SOD activity increased in Zhengjiao 13. There was no H-induced reactive oxygen species production due to increase of RL, NPQ, RSHAM, RKCN and activities of SOD and APX. However, H slightly decreased the PN. The results indicated that HD was more detrimental than either stress alone.