喷锌方式对冬小麦籽粒锌含量和锌利用率的影响

为探究喷锌方式对冬小麦籽粒锌含量和锌利用率的影响，采用人工（M1）和无人机（M2）两种喷施方式，设置5个锌肥施用水平（M1T0~M1T4处理锌肥浓度分别为0、0.4%、0.8%、1.2%、1.6%；M2T0~M2T4处理锌肥浓度分别为0、2.5%、5%、7.5%、10%）和3个锌氮磷肥配施的处理(M1T5: 0.4% ZnSO₄·7H₂O+0.2%K₂HPO₄;M1T6: 0.4% ZnSO₄·7H₂O+2%尿素;M1T7: 0.4% ZnSO₄·7H₂O+0.2%K₂HPO₄+2%尿素；M2T5: 2.5% ZnSO₄·7H₂O +1.25%K₂HPO₄;M2T6: 2.5% ZnSO₄·7H₂O+12.5%尿素;M2T7: 2.5% ZnSO₄·7H₂O+1.25%K₂HPO₄+12.5%尿素)，人工和无人机单次喷施药液量分别为375 和60 L·hm^-2，通过田间试验比较分析了不同处理下冬小麦籽粒锌含量、锌携出量、光合速率、产量等性状的差异。结果表明，同一喷锌量下，人工喷施时冬小麦籽粒锌含量、锌携出量显著高于无人机喷施处理；同一喷施方式下，随着锌肥浓度的提高，籽粒锌含量和锌携出量均呈上升趋势，但无人机喷锌浓度高至10%时对籽粒锌携出量的提升作用反而减弱，旗叶净光合速率、穗粒数、籽粒收获指数和产量也显著降低。与单一施锌相比，人工和无人机锌氮配施均显著提高籽粒锌携出量和锌利用率，且M2T6处理的籽粒产量较M2T1处理显著增加,增幅22.68%。以上结果说明，相同喷锌量下，人工喷施对籽粒锌元素的强化效果优于无人机，但是采用无人机喷施时，将2.5%浓度的硫酸锌溶液与12.5%的尿素溶液配合施用，可实现籽粒产量和锌含量的同步提高。

Effects of Different Zinc Spraying Methods on Grain Zinc Content and Zinc Utilization Rate of Winter Wheat

In order to investigate the effects of different zinc spraying methods on grain zinc content and zinc utilization rate of winter wheat, the experiment was conducted using two spraying methods, manual (M1) and UAV (M2), and five zinc fertilizer application levels were set up (the in zinc fertilizer concentrations M1T0 to M1T4 treatments were 0, 0.4%, 0.8%, 1.2%, and 1.6%, respectively; the zinc fertilizer concentrations in M2T0 to M2T4 treatments were 0, 2.5%, 5%, 7.5%, and 10%, respectively) and three treatments of zinc fertilizer with nitrogen and phosphorus fertilizers (M1T5: 0.4% ZnSO₄·7H₂O+0.2%K₂HPO₄; M1T6: 0.4% ZnSO₄·7H₂O+2% urea; M1T7: 0.4% ZnSO₄·7H₂O+0.2%K₂HPO₄+2% urea; M2T5: 2.5% ZnSO₄·7H₂O+1.25%K₂HPO₄, M2T6: 2.5% ZnSO₄·7H₂O +12.5% urea; M2T7: 2.5% ZnSO₄·7H₂O+1.25%K₂HPO₄+12.5% urea), and the single spraying volume of manual and UAV works were 375 L·hm^-2 and 60 L·hm^-2 , respectively. Some indexes including Zn content and carrying amount in grain, photo synthetic rate in flag leaf, grain yield of winter wheat were compared. The results showed that under the same amount of zinc spraying, the zinc content and zinc carrying amount of winter wheat grain during manual spraying were significantly higher than those of UAV spraying; under the same spraying method, the Zn content and Zn transport of grains tended to increase with increasing Zn fertilizer concentration, but the Zn spraying by drone with the Zn concentration as high as 10% weakened the enhancement of Zn transport of grains, and the net photosynthetic rate of the flag leaf, the number of grains in the spike, the grain harvest index and the yield were also significantly reduced. Both manual and drone zinc and nitrogen applications significantly increased seed zinc carryover and zinc utilization compared to single zinc application, and grain yield of M2T6 treament was significantly increased by 22.68% compared to M2T1 treament. The above results indicated that manual spraying was more effective than drone for seed zinc fortification at the same spraying rate, but the simultaneous increase in frain yield and zinc content can be achieved by using drone and applying 2.5% zinc sulphate solution in combination with 12.5% urea solution.