Nemat Alla Mamdouh M, Hassan Nemat M
Botany Department, Faculty of Science, Damietta University, Damietta, Egypt.
Botany Department, Faculty of Science, Damietta University, Damietta, Egypt.
Pestic Biochem Physiol. 2014 Jun;112:56-62. doi: 10.1016/j.pestbp.2014.04.012. Epub 2014 May 9.
Treatment with the recommended field dose of isoproturon to 7-d-old wheat seedlings significantly decreased shoot height, fresh and dry weights during the subsequent 15days. Meanwhile contents of carotenoids, chlorophylls and anthocyanin as well as activities of δ-aminolevulinate dehydratase (ALA-D), phenylalanine ammonia lyase (PAL) and tyrosine ammonia lyase (TAL) were significantly inhibited. On the other hand, the herbicide significantly increased malondialdehyde (MDA), a naturally occurring product of lipid peroxidation and H2O2, while it significantly decreased the contents of glutathione (GSH) and ascorbic acid (AsA) and reduced the activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). These findings indicate an induction of a stress status in wheat seedlings following isoproturon treatment. However, exogenous GSH appeared to limit the toxic effects of isoproturon and seemed to overcome this stress status. Most likely, contents of pigment and activities of enzymes were raised to approximate control levels. Moreover, antioxidants were elevated and the oxidative stress indices seemed to be alleviated by GSH application. These results indicate that exogenous GSH enhances enzymatic and nonenzymatic antioxidants to alleviate the effects of isoproturon.
用推荐田间剂量的异丙隆处理7日龄小麦幼苗，在随后的15天内显著降低了苗高、鲜重和干重。同时，类胡萝卜素、叶绿素和花青素的含量以及δ-氨基乙酰丙酸脱水酶（ALA-D）、苯丙氨酸解氨酶（PAL）和酪氨酸解氨酶（TAL）的活性均受到显著抑制。另一方面，该除草剂显著增加了脂质过氧化的天然产物丙二醛（MDA）和过氧化氢（H2O2），同时显著降低了谷胱甘肽（GSH）和抗坏血酸（AsA）的含量，并降低了超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和抗坏血酸过氧化物酶（APX）的活性。这些发现表明异丙隆处理后小麦幼苗出现了应激状态。然而，外源GSH似乎限制了异丙隆的毒性作用，并似乎克服了这种应激状态。很可能，色素含量和酶活性提高到了接近对照水平。此外，抗氧化剂增加，施用GSH似乎减轻了氧化应激指标。这些结果表明，外源GSH增强了酶促和非酶促抗氧化剂，以减轻异丙隆的影响。
