Abstract: An experiment was conducted in solar greenhouse to study the effects of graft and different nitrogen (N) supply levels (0, 110, and 331 kg·hm^-2) on the water consumption and water use efficiency (WUE) of cucumber (Cucumis sativus L.) under traditional irrigation. The results showed that when topdressing 331 kg N·hm^-2, the water consumption of grafted cucumber was the highest, being 3 350 m³·hm^-2 and 2 181 m³·hm^-2 in winter-spring and autumn-winter cropping, so did the WUE, being 27.2 kg·m^-3 and 36.9 kg·m^-3, respectively. Comparing with those of self-rooted cucumber, the water consumption, economic yield, and WUE of grafted cucumber under the same N topdressing levels were increased by 3%-6%, 28%, and 20.9%, respectively, and the water consumption and WUE of grafted cucumber were increased with increasing N supply level. The water consumption of self-rooted cucumber also increased with increasing N supply level, but its WUE was the highest when the N supply was 110 kg·hm^-2. It was indicated that graft could markedly promote the water consumption and WUE of cucumber, and the effect was more markedly with increasing N supply level. To increase N supply could also markedly promote the water consumption of self-rooted cucumber, but the WUE would be lower when excessive N was supplied.

Key words: water use efficiency (WUE), ecosystem service, meteorological factor, matching degree of water, soil, and heat resources, Central Asia