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防御酶是植物对昆虫危害的潜在防御机制。毛花雀稗(Paspalum dilatatum)作为一种优良牧草，了解被昆虫取食胁迫后其防御酶的变化很有必要。为此，本研究分析了蝗虫(Oxya chinensis)取食毛花雀稗0 (CK)、24、48、72和96 h后毛花雀稗总抗氧化能力(total antioxidant capacity, T-AOC)、过氧化物酶(peroxidase, POD)、过氧化氢酶(catalase, CAT)、超氧化物歧化酶(superoxide dismutase, SOD)、酪氨酸解氨酶(tyrosine ammonia-lyase, TAL)、多酚氧化酶(polyphenol oxidase, PPO)、脂氧合酶(lipoxygenase, LOX)、谷胱甘肽S-转移酶(glutathione S-transferase, GST)、苯丙氨酸解氨酶(phenylalanine ammonia-lyase, PAL)活性及植物总酚(total phenols, TP)含量的变化规律。结果表明：与不取食对照相比，蝗虫取食后毛花雀稗植株中POD、CAT、LOX、PPO、TAL、GST活性以及TP含量均在部分取食时间或所有取食时间显著升高(P < 0.05)。其中T-AOC在24 h时显著升高(P < 0.05)；TAL、PPO和GST活性均随取食时间的延长呈先升高后降低的变化趋势，分别在48、72和24 h时达到最高，是对照的3.71、2.10和21.25倍。相反，除24 h时SOD活性外，SOD、PAL活性在蝗虫取食胁迫下均显著降低(P < 0.05)。可见，POD、CAT、PPO、TAL、GST和LOX等防御酶在毛花雀稗防御害虫胁迫中发挥了非常重要的保护作用。“,”Defense enzymes are potential defense mechanisms against herbivorous insects in plants. It is important to learn about the changes in protective enzymes in response to insect-induced stresses in excellent forages, such as dallisgrass (Paspalum dilatatum). In the present study, total antioxidant capacity (T-AOC), peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), tyrosine ammonia-lyase (TAL), lipoxygenase (LOX), polyphenol oxidase (PPO), glutathione S-transferase (GST), and phenylalanine ammonia-lyase (PAL), as well as total phenol (TP) content of dallisgrass were investigated at 0, 24, 48, 72, and 96 h after grasshopper (Oxya chinensis) feeding. The results showed that the activities of POD, LOX, CAT, PPO, TAL, and GST as well as the TP content in dallisgrass were significantly increased after grasshopper feeding compared with the control (P < 0.05). T-AOC increased significantly 24 h after feeding (P < 0.05). Moreover, the activities of PPO, TAL, and GST first increased and then decreased over time. At 48, 72, and 24 h of treatment, the activity of TAL, PPO, and GST peaked at 3.71, 2.10 and 21.25 times of CK, respectively. In contrast, grasshopper feeding significantly reduced the activity of SOD and PAL (P < 0.05). Overall, it could be speculated that protective enzymes such as POD, CAT, PPO, TAL, GST, and LOX play very important protective roles against insect herbivores.