Effect of different applied nitrogen amount on the yield of no - tillage and seedling - throwing culture 不同施氮量对免耕抛秧稻产量的影响
2.
Nitrogen protection : apply nitrogen to detect the oxygen amount contained in the machine online ensuring the safe operation 氮气保护系统：采用氮气保护以保证机器在安全的环境下运行。
3.
4 . the results indicated that the applied nitrogen amount had a quadratic curve relation with grain yield . yield and profit increased with the amount of nitrogen applied under a certain amount of nitrogen 田间试验结果表明，施氮量与产量呈二次曲线关系，在一定的施氮量范围内，产量和经济效益都随施氮量增加而提高，超过施氮量阈值，增加施氮量，产量和经济效益下降。
