Sofo Adriano, Dichio Bartolomeo, Xiloyannis Cristos, Masia Andrea
Università degli Studi della Basilicata, Dipartimento di Scienze dei Sistemi Colturali, Forestali e dell'Ambiente, Via dell'Ateneo Lucano 10, 85100, Potenza, Italy.
Università degli Studi di Bologna, Dipartimento di Colture Arboree, viale Fanin 46, 40127, Bologna, Italy.
Funct Plant Biol. 2005 Feb;32(1):45-53. doi: 10.1071/FP04003.
The effects of drought on the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (POD), indoleacetate oxidase (IAAox) and polyphenol oxidase (PPO) were studied in 2-year old Olea europaea L. (cv. 'Coratina') plants grown under high temperatures and irradiance levels and gradually subjected to a controlled water deficit. After 20 d without irrigation, mean predawn leaf water potential fell from -0.37 to -5.37 MPa, and decreases in net photosynthesis and transpiration occurred. The activities of SOD, APX, CAT and POD increased in relation to the severity of drought stress in both leaves and roots. In particular, a marked increase in APX activity was found in leaves of plants at severe drought stress. CAT activity increased during severe water deficit conditions in leaves and fine roots. The patterns of POD and IAA oxidase activity ran in parallel and showed increases in relation to the degree of drought. In contrast, PPO activity decreased during the progression of stress in all the tissues studied. The results show that the ability of olive trees to up-regulate the enzymatic antioxidant system might be an important attribute linked to drought tolerance. This could limit cellular damage caused by active oxygen species during water deficit.
研究了干旱对两年生油橄榄（品种‘科拉蒂纳’）植株中超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、抗坏血酸过氧化物酶（APX）、愈创木酚过氧化物酶（POD）、吲哚乙酸氧化酶（IAAox）和多酚氧化酶（PPO）活性的影响。这些植株在高温和高光照条件下生长，并逐渐遭受可控的水分亏缺。在不灌溉20天后，黎明前叶片平均水势从-0.37兆帕降至-5.37兆帕，净光合作用和蒸腾作用降低。叶片和根系中，SOD、APX、CAT和POD的活性随干旱胁迫的加剧而增加。特别是，在严重干旱胁迫下的植株叶片中，APX活性显著增加。在严重水分亏缺条件下，叶片和细根中的CAT活性增加。POD和IAA氧化酶活性的变化趋势平行，且随干旱程度增加而升高。相反，在所有研究组织中，PPO活性在胁迫过程中降低。结果表明，油橄榄上调酶促抗氧化系统的能力可能是与耐旱性相关的一个重要特性。这可以限制水分亏缺期间活性氧对细胞的损伤。
