| Sandy chestnut soil with drought, roughness and thin soil layer of field accounted for more than 65% of whole cultivated area in north-west of Hebei plateau. Uneven distribution of the rainfall in annual and internet-annual, which maked intra-regional agricultural production low and untable. Aparse planting pumpkin had the special resource utilization property. In the research, using sandy chestnut soil as the experimental soil and using pumpkin as the tested materials, potted experiment and root-bag control experiment were conducted, to study the response of different soil moisture and soil root-growing space to pumpkin and water efficient utilization of root under planting patterns with ridge culture and film mulching on furrow. The main results were as follows:1. Simulating different precipitation years through five water treatments: dry style(W158, CK), normal style (W258), wet style (W358), dry and make-up water style (W178, suppling water at flowering and vine elongation and fruit expanding process of pumpkins, 10mm/once), normal and make-up water style (W278, supplying water at flowering and vine elongation and fruit expanding process of pumpkins, 10mm/once) under the pot experiment condition.The results showed that: Comparing with control, the pumpkin's yield, dry matter quantity and fruit quality increased at different degree. The yield of W178 and W278 treatments reached 18 226.1kg·hm-2and 19 604.5kg·hm-2 respectively, which increased by 102.13% and 117.41%. The water supply quantity of wet style (W358) was more, but its yield was lower than W258, W178 and W278 treatments. The flesh thickness and average fruit weight increased by 26.29%~42.25% and 54.17%~116.67% compared with control. In comparison with control, Vc and starch content increased by 31.25% and 10.48% significantly, protein content increased by 29.26%, pectin content increased by 21.85% with the treatment of W278. In the treatment of W178 and W278, the water use efficiency (WUE) reached 89.57kg·mm-1·hm-2 and 64.76kg·mm-1·hm-2 respectively, which increased by 91.55% and 38.49%.The WUE of W358 treatment was lower than control. Characteristic parameters for the whole roots of W258, W358 and W278 treatments showed increasing trend compared with control. In W278 treatment, the total root length, root length less than 1mm, the total surface area and the total volume were the largest, which were 2.96times, 2.96times, 3.70times and 3.31times than that of control, respectively. The root dry weight increased by 50.05% compared with control. The change of nutrient content of plant for post-harvest showed that: total nitrogen>total potassium >total phosphorus, the content of total nitrogen was the highest in leaves and the content of total potassium was the highest in petiole.The content of available N, P, K and organic matter for post-harvest were lower than d control.2.Comparing with non-bagged (R0), soil culture was conducted with the pumpkin planted in bottom sealing nylon bags of different specifications to confine the space of root growth but allow the pass-through of water and nutrients, the confinement of root growth space decreased the yield, dry matter quantity, fruit quality and water use efficiency. After root restriction culturing, the yield was largest which attained 11 902.9kg·hm-2; dry matter quantity reached 3 182.24kg·hm-2; flesh thickness was 2.80cm, average fruit weight reached 1.42kg; water use efficiency was the highest which reached 56.56kg·mm-1·hm-2 with the treatment of R2 (the port area of root-bag is 0.4m×0.4m, depth is 0.3m). The content of total sugar reached 2.10%, the content of starch reached 47.56%, the content of pectin reached 9.14%, with the treatment of R3 (port area of root-bag is 0.5m×0.5m, depth is 0.3m) which flesh quality was the best effect. The total root length and surface area were higher than control, which increased by 19.60%~97.73%, and 26.41%~96.33%; the total root volume and root length less than 1 mm were lower than control, which increased by 38.12%~54.34% and 81.21%~86.29% in upper soil layer; the total root length, root length less than 1mm, the total surface area and the total volume increased than the control; which were9.04times~23.48times,5.96times~7.83times,11.07times~24.53times,9.76times~15.67 times compared with control, respectively, in lower soil layer after the confinement of root growth space. Root dry weight increased than the control, which increased by 17.01%~77.13%; above-ground dry weight decreased by 37.04%~64.77%; root-shoot ratio decreased by 37.04%~64.77% except treatment R1. The change of nutrient content of plant for post-harvest showed that: total nitrogen>total potassium >total phosphorus, the content of total nitrogen was the highest in leaves and the content of total potassium was the highest in petiole.
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