关键词: 小麦, 外源调节剂, 灌浆, 强势粒, 弱势粒, 产量

Abstract: In order to investigate the yield‑increasing effect of different exogenous regulators on wheat，the semi‑winter wheat cultivars Zhoumai 36 and Bainong 207 were used as materials，and different exogenous regulators［distilled water+emulsifier（Tween 80）（CK1，T1），KH2PO4 +emulsifier（Tween 80）（CK2，T2），salicylic acid+ZnSO₄+MnSO₄+chitin+spermidine+6‑BA+emulsifier（Tween 80）（T3），salicylic acid+ZnSO₄+MnSO₄+H₃BO₃+chitin+phthalanilic acid+brassinolide+emulsifier（Tween 80）（T4），salicylic acid+ ZnSO₄+MnSO₄+H₃BO₃+chitin+phthalanilic acid+spermidine+emulsifier（Tween 80）（T5），salicylic acid+ZnSO₄+MnSO₄+H₃BO₃+chitin+brassinolide+6‑BA+emulsifier（Tween 80）（T6）］were sprayed on the leaves at wheat full‑heading stage and mid‑filling stage，and the effects of different exogenous regulators on superior and inferior grain filling and yield of wheat were explored. The results showed that compared with CK1 and CK2，the 1 000‑grain weight of superior and inferior grains of Zhoumai 36 and Bainong 207 obviously improved under T5 and T6 treatments at 37 d after anthesis；the time of reaching the maximum grain filling rate of inferior grains of Zhoumai 36 and Bainong 207 was advanced under T4，T5 and T6 treatments；at 22 d after anthesis，the grain filling rate of superior grains of the two wheat cultivars obviously increased under T4，T5 and T6 treatments.With the advancement of grain filling，the contribution of superior grains to total grain weight per panicle of wheat generally decreased first and then increased.T3—T6 treatments were beneficial to improve the contribution of inferior grains to total grain weight per panicle of Zhoumai 36 and Bainong 207 at 27 d after anthesis compared with CK1，and the contribution of superior grains to total grain weight per panicle of Zhoumai 36 and Bainong 207 at 37 d after anthesis compared with CK1 and CK2. Compared with CK1 and CK2，the activities of ADP‑glucose pyrophosphorylase（AGP） and soluble starch synthase（SSS） in superior grains and SSS and granule‑bound starch synthase（GBSS）in inferior grains of Zhoumai 36 and Bainong 207 of T3—T6 treatments increased at 25 d after anthesis.Compared with CK1 and CK2，T3—T6 treatments were beneficial to improve the grain number per spike，1 000‑grain weight and yield of Zhoumai 36 and Bainong 207，and the yield increased significantly，T6 treatment was the best，followed by T5 treatment.Under T6 treatment，the yields of Zhoumai 36 and Bainong 207 significantly increased by 14.0% and 9.6% compared with CK1，and 9.7% and 6.1% compared with CK2，respectively. Under T5 treatment，the yields of Zhoumai 36 and Bainong 207 significantly increased by 11.5% and 6.7% compared with CK1，and 7.3% and 3.3% compared with CK2，respectively.In addition，T6 treatment significantly reduced the defective grain number.Overall，application of different exogenous regulators generally can increase the filling rate of both superior and inferior grains，1 000‑grain weight and yield of wheat in different degree，and T6 treatment shows the best effect.

Key words: Wheat, Exogenous regulator, Grain filling, Superior grain, Inferior grain, Yield