陕北沙区滴灌条件下不同水肥组合对马铃薯产量的影响

陕北沙区马铃薯生产中水肥利用效率较低，滴灌水肥一体化技术对该地区马铃薯产量的影响少见报道。研究采用饱和D-416-A最优设计，在滴灌条件下设置16种水肥组合（T1~T16），分析不同水肥组合处理对马铃薯植株光合速率、水分利用效率及马铃薯产量的影响。结果表明，在整个生育期，T10处理（灌水量为5 268.249 m·hm^-2，氮、磷、钾施用量分别为 290.119、290.119、167.449 kg·hm^-2）和T5处理（灌水量为3 131.751 m·hm^-2，氮、磷、钾用量分别为290.119、129.881、167.449 kg·hm^-2）的叶片净光合速率高于其他处理2.95%~192.47%。在块茎形成期，T10处理的叶片水分利用效率最大，T5处理次之。T10处理的马铃薯产量略高于T5处理2.55%，且显著高于其他处理5.30%~99.84%（P＜0.05）。T5处理的马铃薯商品薯率和水分生产率分别较其他处理高4.15%~111.55%和22.44%~152.91%。研究表明，与高水高肥组合相比，T5处理的水肥耦合模式明显节约灌溉用水和磷肥用量，有利于提高马铃薯的产量和商品薯率。

Effect of Different Water-Fertilizer Combinations under Drip Irrigation on Potato Yield in Sandy Area of Northern Shaanxi

The utilization efficiency of water and fertilizer in potato production is low in sandy area of Northern Shaanxi, and the effect of drip fertigation technology on potato yield is rarely reported. In this study, 16 water-fertilizer combinations (T1~T16) were set under drip irrigation by saturated D-416-A optimal design to analyze the effects of different water-fertilizer combinations on the potato yield, photosynthetic rate and water use efficiency of the potato plants.The results showed that during the whole growth period, the net photosynthetic rate of leaves under T10 treatment (irrigation amount was 5 268.249 m·hm^-2, application amount of nitrogen, phosphorus and potassium was 290.119, 290.119 and 167.449 kg·hm^-2, respectively) and T5 treatment (irrigation amount was 3 131.751 m·hm^-2, application amount of nitrogen, phosphorus and potassium was 290.119, 129.881 and 167.449 kg·hm^-2, respectively) were 2.95%~192.47% respectively higher than that of other treatments. During tuber formation stage, T10 treatment had the maximum water use efficiency in leaves, followed by T5 treatment. Potato yield under T10 treatment was 2.55% slightly higher than that under T5 treatment and 5.30%~99.84% significantly higher than that under other treatments (P<0.05). The commercial potato ratio and water productivity under T5 treatment were 4.15%~111.55% and 22.44%~152.91% higher than those under other treatments ,respectively. Compared with the high water and fertilizer combination, the coupling model of water and fertilizer treated with T5 can significantly save the amount of irrigation water and phosphate fertilizer, which is beneficial to improve potato yield and commercial potato ratio.