亚精胺浸种对番茄种子萌发及幼苗高温抗性的影响

以番茄品种合作903为试验材料,设置0、0.1、0.2、0.4 mmol · L~(-1 )亚精胺(Spd)浸种10 h,研究不同浓度Spd浸种对番茄种子萌发、幼苗生长及高温抗性的影响。结果表明:不同浓度Spd浸种处理均能显著提高番茄种子的发芽指数和活力指数,幼苗地下部干质量和壮苗指数明显提高,其中0.2 mmol · L~(-1 )Spd浸种处理发芽最快,活力指数最高。Spd浸种处理降低了高温胁迫下番茄叶片的相对电解质渗透率、丙二醛(MDA)和H_2O_2含量,其中0.2 mmol · L~(-1 )Spd处理的相对电解质渗透率、MDA和H_2O_2含量最低;抗氧化酶(SOD、APX、DHAR)活性增加,并在0.2 mmol · L~(-1)时达到最大值。综上,0.2 mmol · L~(-1 )Spd浸种能有效促进番茄种子萌发和幼苗生长,提高番茄幼苗高温抗性。

Effects of Seed Soaking with Spermidine on Tomato Seed Germination and Seedling Tolerance to High Temperature

Taking tomato（Solanum lycopersicum L. ）variety ‘Hezuo 903’as material，and treating the seeds with 0，0.1，0.2，0.4 mmol · L^-1 spermidine（Spd） for 10 hours，this paper studied the effect of different concentrations of Spd on seed germination，seedling growth and high temperature tolerance．The results showed that the seed soaking treatment with different Spd concentrations could significantly increase the germination index and vigour index of tomato seeds．The underground root dry weight of tomato seedlings and strong seedling index could also be remarkably increased．Among them，the germination rate and vigour index under 0.2 mmol · L^-1 Spd treatment were the fastest and highest．Spd treatment could reduce the relative electrolyte permeability of tomato leaves under high temperature stress，contents of malondialdehyde（MDA）and H₂O₂．The relative electrolyte permeability，MDA and H₂O₂ contents under 0.2 mmol · L^-1 Spd treatment were the lowest，while the activities of antioxidant enzyme（SOD，APX，DHAR）were increased and reached the peak value when treated with 0.2 mmol · L^-1．To sum up，seed soaking with 0.2 mmol · L^-1 Spd treatment could effectively promote tomato seed germination and seedling growth and improve tomato seedlings tolerance to high temperature．