| In the recent years, accompany with ecological environment deterioration in the plateau in the northwest of hebei province, it begins to actively carry out returning farmland and restoring forest and grass under supporting of national policy; Because cultivated areas decreased significantly, peasants, economic incomes reduced. In the recent more than ten years, unseasonal conditions vegetables rapidly develop in meadow chestnut soil, which accounting for 10%~15% of total cultivated areas, and increasing peasants, economic incomes. But the areas of sand chestnut soil, which accounting for 60%~70% of total cultivated areas, donot perform highly exploitating and efficiently utilizing. To better utilize efficiently these resources, it has been become the most important task for local government and technology tackling patients to positively exploit the areas of sand chestnut soil. Pumpkin can be used as both vegetable and food crop. Its economic value is 7~8 times more than naked oats. As it has the characteristics of drought tolerance and suitability for larger spacing planting, it is usually taken as the first candidate crop for increasing economic benefit in arid areas.The thesis adopted the research methods of field experiment combining laboratory experiment, qualitative analysis combining quantitative analysis. In this paper, photosynthetic characteristics of pumpkin was studied, and whether stereo planting pattern of pumpkin and oil sunflower can utilize efficiently light and water resources was studied and analyzed. Reasonable integrated cultural practices of pumpkin were put forward, too. This paper put forward theoretical basis for reasonable integrated cultural practices of pumpkin and utilizing efficiently light and water resources, at the same time, theory and technology was put forward for adjusting production structure of regional crop and utilizing efficiently farmland water and soil resources.The results showed as follow: pumpkin is positive vegetable, its optimum light intensity in seedling stage, vine-expending stage, fruit expansion stage was 887.82~2274.32μmol/m2.s , 1402.74~2523.15μmol/m2.s , 1402.74~2523.15μmol/m2.s, respectively; and it is suitable for ecological characteristics of intense light irradiation in the plateau in the northwest of hebei province, its light compensation point in seedling, vine-expending stage, fruit expansion stage was 257.91～330.8μ8mol/m2.s,181.25～229.2μmol/m2.s,67.96～72.81μmol/m2.s, respectively; its light saturation point in seedling, vine-expending stage, fruit expansion stage was 1828.57～1978.57μmol/m2.s,2110.00～2146.86μmol/m2.s,2128.57～2182.50μmol/m2.s. Pn of single leaf of pumpkin show the tendency of rising firstly and declining finally. The daily change trendency of Pn of leaves in pumpkin showed a double peak curve, and there was a significant"midday depression"at noon; the extent and duration of"midday depression"of pumpkin were stomatal factor more than that of non stomatal factor; whether growth periods, varieties, and leaf positions were or not the same. The daily change trendency of solar energy use efficiency of leaves in pumpkin showed declining firstly, rising, and declining finally.The study on the effect of pumpkin and oil sunflower intercropping system indicated that by analyzing roots and ratio of root to shoot, oil sunflower was dominant in this intercropping system.The root and the above-ground biomass of intercropped pumpkin with oil sunflower were lower than those in sole pumpkin cropping, while those of oil sunflower were just on the contrary; Oil sunflower competed for soil water with pumpkin during later growth stage of pumpkin about cropping two rows oil sunflower between pumpkin rows(J2), but there was no water competition with pumpkin about cropping one rows oil sunflower between pumpkin rows(J1).On condition that precipitation was 201.6mm during whole growth and development period, there was obvious difference between every gradient of water balance in different treatment. The ratio of water percolation was little; and all variations of soil water storage were negative, so almost all water was evapotranspirated by gaseous water, but the evapotranspiration of different treatment were different, the evapotranspiration of J1 was less than ND,YD and J2 for 36.33%,19.00% and 34.87%, respectively. Economic yield of pumpkin decreased from 30.00% to71.42%, but yield per plant of intercropping oil sunflower increased from 190.71% to 241.26% as compared with sole oil sun-flower, because of oil sunflower had laterality effect. The Land Equivalent Ratio (LER) of pumpkin-oil sunflower were 1.08~1.22, and the Water Equivalent Ratio (WER) of pumpkin-oil sunflower were 1.07~1.26, but economic benefit of compound population was similar to sole pumpkin or decreased 20.69%.The results from pumpkin and oil sunflower intercropping system showed that oil sunflower was dominant in this intercropping system.The influenced degree to PAR and temperature of canopy in fruit expansion stage of pumpkin was decreased company with the propulsion of growth period in pumpkin and oil sunflower; The shorter the distance from pumpkin to oil sunflower, the greater the influenced degree to PAR and temperature of canopy in pumpkin, and there was no obvious differences between J1 and J2. Pumpkin and oil sunflower intercropping system decreased the contents of Chl in functional leaves, absorption and transformation efficiency of light energy, which led to Fv/Fm, Fv/Fo and Pn of intercropping pumpkin lower than sole pumpkin. On the background of rain-fed and dry farming, slope pumpkin of sparse planting and efficient could realize regional light and heating resource using efficiently in the plateau of northern Hebei province.The study on the cultural practices for pumpkin showed that the photosynthetic rates of three leaves had very strong compensation effects when source-reduced in fruit early stage. The photosynthetic rates of three leaves had great differences in fruit later stage because of different source-reduced quantities; premature senility phenomenon advanced for the photosynthetic rates of three leaves when 75% source-reduced; photosynthetic characteristics could be maintained well in fruit later stage when 25% source-reduced. The quantities of accumulated dry matters varied as defferent source-sink proportions, The quantities of accumulated dry matters were more than those of CK when 25% source-reduced, less than those of CK when 75% source-reduced. Loading amounts of leaf areas were higher than the treatments of source-reduced, which led to more fluency when photosynthates were transported from source to sink.As pumpkin has the characteristics of drought tolerance, planting density is 14250~16500 plantlets per hm2, which increasing the mulching degree to the ground, decreasing soil water evaporation between rows, improving WUE and the photosynthetic rate and yield. Study on the potassium fertilizer applying rate for pumpkin showed the potassium fertilizer improved the photosynthetic rate, decreased the transpiration rate in leaves, and maintained water contents in leaves; this study also showed the potassium fertilizer promoted stem overstriking and dry matter in per leaf area accumulating, which providing more nutrients and improving obviously yield for pumpkin.On the background of rain-fed and dry farming in the plateau in the northwest of Hebei province, light and heat use efficiency in pumpkin could be increased by improving cultural control methods such as farming soil, adjusting the planting density, collocating optimal source-sink,et al. In addition, supplying nutrients for growth and development of pumpkin by fertility betterment, which could be a real and feasible way to realize regional light and water resource using efficiently for sole cropping pumpkin in the plateau of northern Hebei province.
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