氮素对山栏稻光合作用、产量性状和氮素利用的影响

The Effect of Nitrogen on Photosynthesis, Yield Traits and Nitrogen Utilization of Shanlan Upland Rice

为了提高山栏稻产量,确定山栏稻合理施氮量,改进旱作山栏稻施肥策略,从而探寻山栏稻高效高产生态栽培方式,减少稻田氮素污染。本试验设置了四种施氮量处理:N1 (施氮量90 kg/hm^(2))、N2 (施氮量180 kg/hm^(2))、N3 (施氮量270 kg/hm^(2))和CK (传统不施氮处理),研究两个典型山栏稻品种‘山川24’和‘满坡紫’的产量性状、叶绿素含量、光合速率、植株含氮量、吸氮量和氮素利用效率。结果表明,N2和N3处理相比于CK显著提高山栏稻产量、叶绿素含量和光合速率。其中N3处理产量最高,但N2与N3产量差异不显著,N2在成熟期时光合速率更高。叶、茎和穗的含氮量和吸氮量随施氮量增加而显著增加,N2处理在生育后期具有更高的叶含氮量。N3和N2处理的总吸氮量显著高于N1和CK。相较于N3处理,在成熟期时N2处理茎吸氮量较低,能更好地转运茎中的氮到籽粒中去。N2处理的氮素利用效率各指标基本高于N3处理。从产量和氮素利用两个方面考虑,施氮量180~270 kg/hm;是最适合旱作山栏稻的氮素水平。

The aim of this stud y is to increase the yield of Shanlan upland rice, choose reasonable amount of nitrogen application, improve nitrogen application strategy, explore the ecological, highly efficient and high-yield cultivation method of Shanlan upland rice and reduce nitrogen pollution in paddy field. In this experiment, four kinds of nitrogen application treatments: N1(90 kg/hm^(2)), N2(180 kg/hm^(2)), N3(270 kg/hm^(2)) and CK(traditional cultivation method with no nitrogen treatment) were set up to study the yield characters, chlorophyll content,photosynthesis rate, plant nitrogen content, nitrogen uptake and nitrogen use efficiency of two typical Shanlan upland rice cultivars, ’Shanchuan24’ and ’Manpozi’. The results showed that N2 and N3 treatments significantly increased the yield, chlorophyll content and photosynthetic rate of Shanlan rice compared with CK. The yield of N3 treatment was the highest, but there was no significant difference between N2 and N3, and the photosynthetic rate of N2 was higher in mature stage. The nitrogen content of leaf, stem and panicle increased significantly with the increase of nitrogen application, and N2 treatment had higher leaf nitrogen content in the later growth stage.The total nitrogen uptake of N3 and N2 was significantly higher than that of N1 and CK. Compared with N3 treatment, N2 treatment had lower nitrogen uptake in stem at mature stage and could transport nitrogen from stem to grain more efficiently. The nitrogen use efficiency of N2 treatment was basically higher than that of N3 treatment.To sum up, the nitrogen application amount of 180~270 kg/hm;is the most suitable nitrogen level for Shanlan upland rice.