Abstract Root-knot nematodes are one of the important phytoparasites that adversely affect the growth and development in plants, thus affecting its productivity. Various chemical nematicides are available commercially, having adverse effect on the environment and non-target organisms. So, it becomes necessary to explore some eco-friendly strategies to manage these parasites. Polyamines recognised as potential phytohormone, enhance the plant survival during stressful conditions. Thus, present study was undertaken to evaluate the stress protective properties of two polyamines in tomato seedlings under nematode stress. Uniform sized tomato (cv. Pusa Ruby) seeds were sterilized and treated with different concentrations (0.5, 0.7 and 0.9 mM) of two polyamines i.e. putrescine and spermine. Seeds are allowed to germinate in in-vitro conditions and subjected to nematode inoculation with second stage juveniles of Meloidogyne incognita @5J2s per seedlings after germination. Various morphological and biochemical parameters were analysed after one day of nematode inoculation. Nematode invasion alters the morphological and biochemical parameters whereas polyamines treatment restores them to control level. Significant decrease in specific activities of antioxidative enzymes viz: superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase, glutathione peroxidase, polyphenol peroxidase, and pyrogallol peroxidase was observed in polyamines treated seedlings except guaiacol peroxidase and phenylalanine lyase with maximum activity change by spermine application comparing with nematode inoculated seedlings. Chlorophyll content also increases significantly with spermine treatment. Non-enzymatic antioxidants analysis also revealed the anti-stress properties of polyamines as the total phenolic, ascorbic acid content significantly increases whereas decreased glutathione content was observed with polyamine application. Results obtained from confocal microscopy also revealed the inhibition of reduced glutathione and H2O2 content in polyamine treated seedlings indicated by weak intensity of fluorescence when compared with nematode inoculated seedlings with lower intensity in spermine applied seedlings.

中文翻译：

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多胺通过改变理化属性诱导番茄线虫胁迫耐受性

摘要 根结线虫是重要的植物寄生虫之一，对植物的生长发育产生不利影响，进而影响其生产力。市场上有多种化学杀线虫剂，对环境和非目标生物有不利影响。因此，有必要探索一些生态友好的策略来管理这些寄生虫。多胺被认为是潜在的植物激素，可在压力条件下提高植物的存活率。因此，本研究旨在评估两种多胺对线虫胁迫下番茄幼苗的胁迫保护特性。将大小均匀的番茄（cv. Pusa Ruby）种子灭菌并用不同浓度（0.5、0.7 和 0.9 mM）的两种多胺，即腐胺和精胺进行处理。允许种子在体外条件下发芽，并在发芽后用第二阶段的南方根结线虫@5J2s 幼苗接种线虫。线虫接种一天后分析各种形态学和生化参数。线虫入侵改变了形态和生化参数，而多胺处理将它们恢复到控制水平。在多胺处理的幼苗中观察到抗氧化酶的比活性显着降低，即：超氧化物歧化酶、过氧化氢酶、抗坏血酸过氧化物酶、谷胱甘肽还原酶、谷胱甘肽过氧化物酶、多酚过氧化物酶和连苯三酚过氧化物酶，除了愈创木酚过氧化物酶和苯丙氨酸裂解酶，与精胺的最大活性变化比较用线虫接种幼苗。随着精胺处理，叶绿素含量也显着增加。非酶抗氧化剂分析还揭示了多胺的抗应激特性，因为总酚类、抗坏血酸含量显着增加，而在多胺应用中观察到谷胱甘肽含量降低。从共聚焦显微镜获得的结果还表明，与使用精胺的幼苗中强度较低的线虫接种幼苗相比，多胺处理的幼苗中减少的谷胱甘肽和 H2O2 含量受到抑制，荧光强度较弱。抗坏血酸含量显着增加，而使用多胺观察到谷胱甘肽含量降低。从共聚焦显微镜获得的结果还表明，与使用精胺的幼苗中强度较低的线虫接种幼苗相比，多胺处理的幼苗中减少的谷胱甘肽和 H2O2 含量受到抑制，荧光强度较弱。抗坏血酸含量显着增加，而使用多胺观察到谷胱甘肽含量降低。从共聚焦显微镜获得的结果还表明，与使用精胺的幼苗中强度较低的线虫接种幼苗相比，多胺处理的幼苗中减少的谷胱甘肽和 H2O2 含量受到抑制，荧光强度较弱。