三唑酮种子包衣对冬小麦种子萌发和幼芽抗逆因子的影响

Effects of triadimefon on seed germination and stress resistance related factors of shoots when coated on winter wheat seeds

为评价三唑酮种子包衣对冬小麦种子萌发的安全性,以苯醚甲环唑为对照药剂,研究了不同包衣剂量三唑酮对周麦22和铭贤169小麦种子发芽及周麦22抗逆相关生化因子的影响。结果表明:周麦22和铭贤169小麦种子发芽指数、种子活力指数和发芽率均与三唑酮包衣剂量呈负相关,且符合指数方程Y=A+B×e(-x/k),但铭贤169种子发芽指数、种子活力指数和发芽率对三唑酮剂量变化更敏感;三唑酮种子包衣能引起小麦幼芽体内赤霉素(gibberellins,GAs)含量降低和脱落酸(abscisic acid,ABA)含量升高,且GAs含量下降程度和ABA水平升高程度均随三唑酮包衣剂量的增加而增加,从理论上解释了三唑酮可对小麦种子萌发产生抑制作用且抑制作用与包衣剂量相关的原因。但通过对幼芽相关抗逆因子的研究表明,三唑酮包衣有利于新长成幼芽中叶绿素含量、根系呼吸速率、可溶性蛋白质含量和α-淀粉酶活性的增加以及细胞膜通透性降低,说明三唑酮包衣在一定程度上有助于新长出幼芽抗逆性的增加。相比之下,苯醚甲环唑对小麦种子萌发的抑制作用比三唑酮小,且更有利于幼芽抗逆性增加。

In order to evaluate the security of triadimefon coated on winter wheat seeds, different doses of triadimefon were coated on wheat seeds and its effects on the germination of wheat seeds, as well as the stress resistance related biochemical factors of wheat shoots were studied, comparing with that of difenoconazole. The results indicated that the germination index, seed vigor index and germination rate of Zhoumai 22 and Mingxian 169 were all negatively correlated with the dose of triadimefon, and the relationship satisfied with function Y = A ＋ B x e（ -x/k） ; however, the variations of Mingxian 169 was more sensitive to the dose of triadimefon. The triadimefon treatment could lead to lower gibberellins （GAs） contents and higher abscisic acid （ABA） contents in shoots when compared to the blankcontrol, and the variations of GAs and ABA contents showed increased trends with the increase of triadimefon doses, which theoretically explained the dose dependent suppression of triadimefon on wheat seed germination. But the biochemical analysis revealed that triadimefon could increase the chlorophyll content, respiratory rate, soluble protein content and a-amylase activity in wheat shoots, and decrease the electrolyte leakage of shoot cells, which suggested that coated triadimefon would be helpful to some extent to improve the potential stress resistance of wheat shoots. Comparatively, difenoconazole showed less suppression on wheat seed germination and was more helpful to improve the potential stress resistance of wheat shoots when compared to triadimefon.