| In order to explore the response of the nitrogen source concentration of pineapple and the mechanism of nitrogen absorption and utilization,this paper takes"golden pineapple"as the material to analyze the dynamic changes of nitrogen and carbon-related products,nitro-nitrogen and ammonium nitrogen and phosphorus and potassium content under the treatment of different concentrations of NH4NO3.Three concentration gradients were used during the test:high nitrogen concentration（90 mmol.L-1）,medium nitrogen concentration(60 mmol L-1),low nitrogen concentration(30 mmol L-1),for ease of understanding,is represented by LN（Low nitrogen）、MN（Medium nitrogen）、HN（High nitrogen）.The main results obtained are as follows:1.Nitrogen fertilization application concentration has a significant effect on the value content of pineapple plant leaves SPAD（Soil and plant analyzer develotrnent）,and the SPAD value of pineapple leaves under MN treatment is 59.275,significantly larger than the other treatments.2.Nitrogen fertilization application concentration has a significant effect on the upper carbon metabolites of pineapple ground.The fructose content and soluble total sugar content of the above-ground part of the pineapple plant under LN and HN treatment were significantly reduced,and there was a significant positive correlation between the soluble total sugar and fructose,the content of sucrose and glucose on the ground of the pineapple plant under LN treatment was significantly increased,and the starch content of the above-ground part of the pineapple plant under The LN and HN treatment was significantly increased.There is a significant positive correlation between sucrose and glucose and starch.3.The application concentration of nitrogen fertilizer also had an effect on the accumulation of nitrogen metabolites on the ground of pineapple.After treatment of 7 d,the content of the above-ground soluble protein content of the HN treatment pineapple plant was significantly higher than that of the water group（CK1）and MS nutrient solution（CK2）,and there was no other nitrogen concentration treatment between the treatment of the water group（CK1）and the MS nutrient solution（CK2）treatment.Differences;nitrogen fertilization concentration has an effect on the nitrogen content of the above-ground part of the pineapple plant,and the nitrogen content of the above-ground nitrogen in the pineapple plant is significantly higher than that of the water group（CK1）and MS nutrient solution（CK2）after treatment of 7 d.After the application of nitrogen fertilizer in different concentrations,there was a difference in ammonium nitrogen content on the ground of pineapple plants,m N treatment,HN treatment of pineapple plant on the ground ammonium nitrogen content significantly higher than MS nutrient solution（CK2）treatment and clean water group（CK1）,LN treatment of the above-ground ammonium nitrogen content of pineapple plant plant and the MS nutrient solution（CK2）treatment and water group（CK1）.4.The concentration of nitrogen fertilizer application also had an effect on the total nitrogen content of pineapple plants.After treatment of 7d,there was no difference between the total nitrogen content of the above-ground part of the pineapple plant treated by HN treatment and MN,which was significantly lower than the total nitrogen content of the above-ground part of the pineapple plant treated with MS nutrients solution（CK2） treatment,and there was no difference between the total nitrogen content of the above-ground part of the pineapple plant treated by the MS nutrition solution（CK2）treatment,and there was no difference in the total nitrogen content of the above-ground part of the pineapple plant.Compared with the treatment of 1 d,the total nitrogen content of the underground part of the pineapple plant under the treatment of 7 d was significantly reduced,the total nitrogen content of the underground part of the pineapple plant under MN treatment was significantly increased,the total nitrogen content of the above-ground part of the pineapple plant under LN treatment and MN treatment was significantly increased,and the total nitrogen content of the above-ground part of the pineapple plant under LN treatment was significantly reduced.5.The concentration of nitrogen fertilizer had no significant effect on the phosphorus content of pineapple plants.After 7d treatment,MS Nutrition Liquid（CK2）treated the underground part of the pineapple plant,and the above-ground phosphorus content was significantly higher than other treatments.The underground and above-ground content of pineapple plants is no different from the above-ground treatment（CK1）of pineapple plants treated with clean water.6.The concentration of nitrogen fertilizer application had no significant effect on the potassium content of pineapple plants.There was no significant difference in potassium content in the above and underground parts of the treated pineapple plants,and the potassium content in the above-ground part of each treated pineapple plant was lower than that of underground potassium.In summary,Under the treatment of low nitrogen concentration,the nitrogen content,glucose content,sucrose content and starch content of the pineapp1le plant were increased,and the nitrogen content of nitination was significantly higher than that of other treatments.Under the treatment of medium nitrogen concentration,the above-ground nitrogen content and ammonium nitrogen content of the pineapple plant increased,the soluble protein content,the nitrogen content decreased,and the SPAD value and ammonium nitrogen content were significantly higher than that of other treatments.Under the treatment of high nitrogen concentration,the above-ground nitrogen content,nitrous nitrogen content and soluble protein content decreased,the starch content and ammonium nitrogen content were increased,the starch content and soluble protein content were significantly higher than other treatments.The nitrogen treatment of each concentration had no significant effect on the absorption of phosphorus and potassium elements in the pineapple plants... |
