滴灌水肥一体化钾肥施用方式对玉米钾素吸收利用的影响

通过膜下滴灌水肥一体化技术，在灌溉定额150 mm、总施K₂O 80 kg/hm²条件下，2019、2020通过对5个处理按照不同生育时期进行不同分配比例施肥，研究不同方式施肥对吉林省西部半干旱区玉米产量和钾素吸收利用的影响。结果表明，钾肥分次施用处理的产量显著高于钾肥全部基施处理，以K4处理(钾肥30%基肥、25%拔节追肥、40%大喇叭口追肥、5%抽雄追肥)产量最高。2019、2020两年产量相比全部基施处理高5.3%和5.6%。对于钾素的吸收，植物吸钾的高峰期为大喇叭口期-抽雄期，其次为拔节-大喇叭口期，两年分别达121.1、119.35 kg/hm²。K4处理的钾肥利用率、钾肥偏生产力和钾肥农学效率均为最高，钾肥利用率达49.04%、50.71%，明显提高玉米钾素利用效率。将钾肥基施与追施相结合，相比于全部基施和全部追施，能提高玉米对钾肥的吸收与利用，进而提高产量。

Effects of Potassium Application Methods on Potassium Absorption and Utilization of Maize under Drip Irrigation of Fertigation

Through the integrated technology of water and fertilizer under drip irrigation, in the irrigation quota of 150mm, the total application of K₂O 80 kg/ha conditions, the effects of different fertilization methods on maize yield and potassium absorption and utilization in the western semi-arid area of Jilin province were studied in five treatments by applying fertilizer according to different distribution proportion in different growth stages in 2019 and 2020. The results showed that the yield of the treatment of potassium fertilizer application in different growing stages was significantly higher than that of the treatment of potassium fertilizer application all as bases, and K4 treatment (potassium fertilizer 30% base fertilizer, 25% jointing topdressing, 40% bell top dressing, 5% tasseling topdressing) had the highest yield, the yield of K4 was 5.3% and 5.6% higher than that of K1 in 2019 and 2020. As for the absorption of potassium, the peak period of plant potassium absorption was from trumpet to tassel stage, followed by jointing to trumpet stage, reaching 121.1 kg/ha and 119.35 kg/ha respectively in two years. Among them, K utilization rate, K partial productivity and K agronomic efficiency of K4 treatment were all higher than those of other treatments. The utilization rate of potassium fertilizer reached 49.04% and 50.71%. Utilization efficiency of maize potassium was improved obviously. Therefore, the combination of potassium fertilizer base application and topdressing can improve the absorption and utilization of potassium fertilizer in maize, and then increase the yield, compared with all base application and all topdressing.