Effects Of Different Irrigation Methods And Nitrogen Application Rate On Nutrient Uptake And Yield Of Rice

To explore application on rice nitrogen efficient irrigation combination mode, under the pot experiment conditions, the two factors of water and nitrogen, nitrogen and five levels of experimental design of water and nitrogen of different combinations of the No. 5 japonica cultivated rice dry matter accumulation and root dry matter accumulation, plant height, number of tillers, root volume, SPAD value, yield components factors and yield, crude protein content, nitrogen, phosphorus and potassium accumulation and soil alkali hydrolyzable nitrogen content. The main results are as follows:(1) The trend of dry matter accumulation of rice on the ground and under the ground is roughly the same, with the advancement of the growth period, the maximum value is reached in the harvest period. The effect of irrigation on dry matter accumulation was controlled by the simultaneous control of nitrogen fertilizer. Under the same irrigation treatments, the rice on the ground, underground dry matter accumulation with the applied amount of nitrogen increased and increased first and decreased after; under the same nitrogen level, control water treatment and root dry matter accumulation was higher than that of the irrigation treatments.(2) The effect of irrigation and nitrogen application level on plant height was significant. Under the same nitrogen application rate, the plant height of water control treatment was higher than that of conventional irrigation treatment. In the tillering stage, jointing stage and flowering stage, the height of the rice plant was increased.(3) The amount of nitrogen fertilizer could increase the tiller number, and the excessive application of N fertilizer could decrease the tiller number and increase the number of tiller.(4) At different growth stages of rice root volume trend roughly the same: the same application rate of nitrogen level, control water treatment of root volume was significantly higher than that of normal irrigation treatment, excessive application of nitrogen fertilizer will inhibit the growth of rice root volume, the best fertilization nitrogen N3.(5) Content of chlorophyll content(SPAD) with the advance of growth stage and increased at first and then decrease, milky stage began leaves became yellow and chlorophyll content decreased significantly. During the same period with one irrigation treatment of rice SPAD value increased with the increase of amount of nitrogen fertilizer; the same period in the same amount of nitrogen under, rice tillering stage and milky stage SPAD value had no significant difference, jointing and anthesis water control rice SPAD value is higher than that of the conventional irrigation treatments.(6) The results showed that the effect of irrigation and nitrogen application on Yield and yield components of rice reached a significant level. Under the same nitrogen fertilizer level, the indicators of controlling water treatment W0 were significantly higher than those of conventional irrigation W1. Under the same irrigation treatment, the indexes increased first and then decreased with the increase of N application rate. Conventional irrigation and water control treatment are 2.204 g-1(N3) of the nitrogen application rate. According to the yield and the amount of nitrogen applied to fit the yield effect equation: conventional irrigation conditions: y=-7.8783x2+24.354x+57.299, which R2=0.6712; under water control irrigation conditions: y=-6.3585x2+21.767x+65.079, which R2=0.8305. Can be obtained, the irrigation under the condition of optimum basal fertilizer is 1.546g- basin- 1, the yield as the bowl 76.120g/; control under the conditions of water yield the best basal fertilization amount for 1.712g- basin- 1, and the yield is 83.708g- basin- 1. Comprehensive analysis of rice yield components of the indicators, in the same conditions under the same amount of nitrogen control water effect is better than conventional irrigation.(7) In the milk stage, the crude protein of rice plants began to transfer to the grain, and the crude protein content of rice plants increased first and then decreased with the increase of the growth stage. In the five growth stages, the highest crude protein content of rice plants was the water and nitrogen combination of N3 under water control treatment.(8) There was a synergistic effect of nitrogen, phosphorus and potassium in the plant, and the change trend was basically the same. Under the same irrigation condition, the content of nitrogen, phosphorus and potassium increased first and then decreased with the increase of nitrogen application rate, and the content of nitrogen, phosphorus and potassium in Rice under the same nitrogen application rate was better than that of conventional irrigation. Therefore, the best treatment for water control treatment under the N3 nitrogen fertilizer level.(9) The nitrogen content(0~15cm) in the upper soil of the same treatment was more than that in the lower layer(15cm) in each period. Under the same irrigation treatment, the amount of alkali soluble nitrogen in paddy soil decreased first and then increased with the increase of N application rate. In the same period, the content of alkali solution nitrogen in the upper and lower layers of the upper layer and the lower layer was basically the same. Integrated water and nitrogen effect, nitrogen content in the lower soil was the lowest in the treatment of N3 in water control treatment.