Abstract:

In order to explore the optimum nitrogen applying level of precise and quantitative fertilizer application of ratoon rice in south Henan province, a field experiment was conducted to compare and analyze the growth of rice, occurrence of disease and insect pests, lodging and yield of rice under different nitrogen fertilization conditions, with Liangyou 6326 as material, and obtain the optimum nitrogen content by fitting the economic benefit curve. The results showed that, the yield of two seasons was the highest when the nitrogen fertilizer amount of main rice and ratoon rice was 14 kg/667 m2 and 8 kg/667 m2, respectively. Under this condition, the main rice has appropriate group, photosynthetic rate is normal in later stage of growth, occurrence of lodging and sheath blight are less, has more dry matter accumulation of stem-sheath in mature period, and is good for the germination of high level regeneration bud. Through the economic benefit curve fitting, the result showed that, the suitable N application amount of Liangyou 6326 as ratoon rice is 27.54 kg/667 m2, and the yield could reach 847.11 kg/667 m2.

Key words: the south Henan province, ratoon rice, precise and quantitative cultivation techniques, nitrogen fertilizer

摘要：

为探讨豫南稻区再生稻精确定量施肥技术的最佳用氮量，以杂交籼稻两优6326为材料，比较分析了5个不同施氮水平条件下的水稻生长、病虫害发生、倒伏等情况及产量表现，并通过经济效益曲线拟合，得出最佳用氮量。结果表明，以头季稻施氮14.8 kg/667 m2、再生季施氮9.0 kg/667 m2时再生稻两季产量均较高。在此施肥水平，头季稻群体适宜，后期光合速率正常，纹枯病危害和倒伏相对较轻，成熟期茎鞘干物质积累较多，有利于高节位再生芽的萌发。经济效益曲线拟合结果显示，杂交籼稻两优6326作再生稻种植全生育期适宜施N量为27.5 kg/667 m2，产量可达847.11 kg/667 m2。

关键词: 豫南稻区, 再生稻, 精确定量栽培技术, 氮肥用量