Effects Of Drip Irrigation Fertigation Frequencies On Yield,Quality,Water And Nitrogen Utilization Of The Facility Radish

In recent years, with the increase of agricultural production intensification level fertigation integration technology in the domestic application of facilities agricultural cultivation also get rapid development, but there are less research of fertigation management mode. This paper mainly studies under the condition of drop irrigation integration of water and fertilizer in different fertilization frequency the influence of radish growth and water and fertilizer use efficiency. Under the condition of same irrigation quota and fertilizer, after the radish seedling by setting different fertigation frequencies, the topdressing urea points 1, 2, 4, 8 times into the test area. After off-test analyzing the fertilizing frequency treatment on the effects of radish yield, quality and water and fertilizer use efficiency, and using HYDRUS-3D software to simplify simulate the spatial distribution of soil nitrate nitrogen, the conclusions are as follows.(1) In the growth period the growth situation of Radish have close relation to fertilization frequency. The fertilization time of high fertilization frequency treatment relatively early, and each time the fertilizing amount in the whole growth period distribute uniform. So it can be in time provide moderate nutrients for radish in each growth period to keep the radish growth faster. Low fertilization frequency treatment radish get nutrient supply time a little late, and fertilization time is relatively concentrated, single fertilizing amount is large. Over a period of time after fertilization radish grow faster, but due to the late fertilizer run off with water the radish growth rate slow down.(2) Fertilization frequency have less effect on the quality of radish. With the increase of fertilization frequency, the content of radish fleshy root vitamin C have a tendency to increase, but amplification is little. Fertilization frequency has great influence on the nitrate accumulation of fleshy root. High frequency treatment have significant differences between low frequency treatment, but the nitrate accumulation within the scope of the permission, which won’t impact the radish quality.(3) Appropriate increase fertilization frequency will have auxo-action for radish yield. Fertilization frequency increased from 2 to 4 times of radish has great auxoaction for increase production, increased from four to eight times radish yield is increased, but the difference was not significant, which show that under the higher fertilization frequency continue to increase fertilization frequency has less effect on radish yield increasing.(4) Increase fertilization frequency contribute to improve facilities radish water and fertilizer use efficiency. Increased fertilizer frequency can make fertilizer frequent small amounts into the radish root active layer to make the soil moisture, nutrient content keep at a suitable level during whole growth period of radish. So the radish can fully absorb and make use of irrigation water and fertilizer to realize high efficient water-saving and increase production, accordingly to improve the utilization efficiency of irrigation water and fertilizer.(5) Using HYDRUS-3D model can better simulate spacial distribution of soil nitrate nitrogen under different fertilization frequency.