尿石素A浸种对玉米种子活力和萌发的影响

Effect of Seed Soaking with Urolithin A on Seed Vigor and Germination of Maize

种子活力的高低直接影响种子萌发、幼苗生长及后期植株的产量和品质。活力低的种子通过浸种(引发)处理可提高种子活力。尿石素A(UA)是一种可重启线粒体自噬和延长秀丽线虫寿命的天然化合物。以老化5 d的郑单958玉米种子(发芽率约为60%)为材料,分别用0、0.5、2.5、5.0、25.0、50.0和100.0μmol/L尿石素A浸种12 h,探究UA浸种对种子活力和萌发的影响。结果发现,用不同浓度的UA浸种均不同程度地促进种子提前萌发,提高发芽率,增幅为3.67%~26.33%,25μmol/L尿石素A浸种效果最好。通过体内、体外实验分析UA对种胚中主要活性氧清除酶活性的影响,发现均显著提高过氧化物酶(POD)、过氧化氢酶(CAT)和超氧化物歧化酶(SOD)的酶活性,降低丙二醛(MDA)含量。用UA浸种可能通过提高体内活性氧清除酶的活性,进而增强种子的发芽能力。

The level of seed vigor directly influences seed germination,seedling growth and the yield and quality of plants.Pre-soaking(or priming)is a simple technique to improve seed vigor.Urolithin A(UA)is a natural compound that reactivates mitochondrial autophagy and prolongs the lifespan in Caenorhabditis elegans.In this study,maize Zhengdan958 seed aged for 5 days(germination rate of about 60%)were soaked with 0.5,2.5,5.0,25.0,50.0 and 100.0μmol/L UA for 12 h,respectively,to explore the effect of seed soaking with UA on seed vigor and germination.The results showed that soaking with UA could promote seed germination in advance and increase the germination rate by 3.67%-26.33%,especially the effect of 25μmol/L UA treatment.Antioxidation tests performed in vitro and in vivo revealed that UA obviously enhanced the activities of peroxidase(POD),catalase(CAT)and superoxide dismutase(SOD),and decreased the malondialdehyde(MDA)levels.In conclusion,the present results suggested that soaking with UA could improve seed germination ability by enhancing the activities of antioxidant enzymes.