PDF(Pubmed)
Abstract：
Being a universal reducing agent nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) plays an important role in the cellular metabolism and the implementation of anti-stress reactions in plants. There are only a few enzymes that ensure the NADPH pool formation in cells. Among them, the most important are glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49), malate dehydrogenase decarboxylating (DMDH, malic enzyme, EC 1.1.1.40) and NADP-isocitrate dehydrogenase (NADP-IDH, EC 1.1.1.42). The presented investigation is devoted to studying the influence of the individual and combinative effects of NaCl and γ-radiation as abiotic stress factors on biometric indicators and activity of these NADPH-generating enzymes, on organic content, and the formation of paramagnetic centers as defense reaction in corn (Zagatala-68 genotype) sprouts. It was found that 100 mM NaCl had an inhibitory effect on the development of sprouts. Relatively lower doses (50 Gy and 100 Gy) of γ-radiation had a positive, but its higher doses (150 Gy and 200 Gy) had a negative effect on this process. 500 Gy was a lethal dose (LD) for the corn sprouts. Combinative stress in all cases considerably delayed the development of sprouts. G6PDH showed the highest activity in the first, whereas, NADP-IDH showed the same activity in the last days of the experiment. All three enzymes, especially the G6PDH, have been activated in both root and stem tissues under the influence of stress factors (either radiation or salt). Combinative stress (γ-radiation + salt) also led to an induction of these activities which was necessary to neutralize the negative consequences of stress factors. Stress factors in all cases also had a negative effect on the content of organic matter in seedlings. Ionizing gamma radiation, which resulted in the formation of new paramagnetic centers as an anti-stress defense reaction in many cases was observed in wheat seedlings, but not in corn sprouts, which clearly shows that there are some differences in the protective mechanisms of these C3- and C4-types of plants to γ-radiation.
摘要：
烟酰胺腺嘌呤二核苷酸磷酸氢（NADPH）是一种通用还原剂，在植物的细胞代谢和抗逆境反应的实施中起着重要作用。仅有几种酶确保细胞中NADPH池的形成。其中,最重要的是葡萄糖-6-磷酸脱氢酶(G6PDH，EC1.1.1.49),苹果酸脱氢酶脱羧（DMDH，苹果酸酶，EC1.1.1.40)和NADP-异柠檬酸脱氢酶(NADP-IDH，EC1.1.1.42)。本研究致力于研究NaCl和γ辐射作为非生物胁迫因素的个体和组合效应对生物识别指标和这些NADPH生成酶活性的影响，关于有机含量，和顺磁性中心的形成作为玉米（Zagatala-68基因型）芽中的防御反应。发现100mMNaCl对芽的发育具有抑制作用。相对较低剂量（50Gy和100Gy）的γ射线呈阳性，但它的高剂量（150Gy和200Gy）对这一过程有负面影响。500Gy是玉米芽的致死剂量(LD)。在所有情况下，组合应激都大大延迟了芽的发育。G6PDH在第一，然而,NADP-IDH在实验的最后几天显示出相同的活性。这三种酶,尤其是G6PDH,在胁迫因素（辐射或盐）的影响下，根和茎组织都被激活。组合胁迫（γ-辐射盐）也导致这些活动的诱导，这对于中和胁迫因素的负面影响是必要的。在所有情况下，胁迫因素对幼苗中有机质的含量也有负面影响。电离辐射,这导致了新的顺磁性中心的形成，在许多情况下，在小麦幼苗中观察到一种抗胁迫防御反应，但不是玉米芽，这清楚地表明，这些C3和C4类型的植物对γ辐射的保护机制存在一些差异。
