Dalal Monika, Khanna-Chopra Renu
Stress Physiology Laboratory, Water Technology Centre, Indian Agricultural Research Institute, New Delhi 110012, India.
Physiol Plant. 2001 Mar;111(3):297-304. doi: 10.1034/j.1399-3054.2001.1110306.x.
The leaves of necrotic hybrid of wheat (Triticum aestivum L.) exhibited high superoxide content associated with increased lipid peroxidation and membrane damage in earlier studies (Khanna-Chopra et al. 1998, Biochem Biophys Res Commun 248: 712-715; Dalal and Khanna-Chopra 1999, Biochem Biophys Res Commun 262: 109-112). In the present study, we investigated the activities of the antioxidant enzymes in the leaves of necrotic wheat hybrids, KalyansonaxC306 (KxC) and WL711xC306 (WLxC) and their parents at different developmental stages. The KxC hybrid exhibited more severe necrosis than WLxC. In KxC, superoxide dismutase (SOD) activity showed no increase over the parents, while WLxC showed an early increase, but it was possibly insufficient to scavenge increased superoxide. Activities of guaiacol peroxidase, ascorbate peroxidase and glutathione reductase were enhanced, while catalase exhibited a decrease in activity, with the appearance of visible necrosis in both the hybrids. The isozyme profile of the antioxidant enzymes was similar in the hybrids and their parents. One existing isoform of guaiacol peroxidase showed an early appearance in the hybrid and increased in intensity with the progression of necrosis. The results reveal a differential response of antioxidant enzymes in necrotic wheat hybrids as compared to their parents. The response differed in magnitude at developmental stages of the leaves, which might be related to the intensity of necrosis expressed by the hybrids.
在早期研究中（Khanna - Chopra等人，1998年，《生物化学与生物物理研究通讯》248: 712 - 715；Dalal和Khanna - Chopra，1999年，《生物化学与生物物理研究通讯》262: 109 - 112）发现，坏死型小麦（Triticum aestivum L.）杂交种的叶片表现出高超氧化物含量，同时伴随着脂质过氧化增加和膜损伤。在本研究中，我们调查了坏死型小麦杂交种KalyansonaxC306（KxC）和WL711xC306（WLxC）及其亲本在不同发育阶段叶片中抗氧化酶的活性。KxC杂交种表现出比WLxC更严重的坏死症状。在KxC中，超氧化物歧化酶（SOD）活性与亲本相比没有增加，而WLxC则早期增加，但可能不足以清除增加的超氧化物。随着两个杂交种中可见坏死症状的出现，愈创木酚过氧化物酶、抗坏血酸过氧化物酶和谷胱甘肽还原酶的活性增强，而过氧化氢酶活性则降低。杂交种及其亲本中抗氧化酶的同工酶谱相似。愈创木酚过氧化物酶的一种现有同工型在杂交种中早期出现，并随着坏死的进展强度增加。结果表明，与亲本相比，坏死型小麦杂交种中抗氧化酶的反应存在差异。在叶片发育阶段，这种反应在程度上有所不同，这可能与杂交种所表现出的坏死强度有关。
