模拟氮沉降对水稻生长、产量及光合特性的影响

Effects of Simulated Nitrogen Deposition on Growth,Yield and Photosynthesis of Rice(Oryza sativa L.)

田间试验研究4种水平的模拟氮沉降(即N0、N1、N2、N3、N4,施氮量分别为0、3、6、12、24 g/(m2.a)对早稻品种"岳优463"不同生长发育阶段的影响。结果表明,氮沉降对水稻的生长、产量及光合作用有一定的促进作用。经高氮沉降(N4)处理,水稻株高、光合速率在分蘖期分别比对照(N0)增加了45.6%和49.5%,在乳熟期比对照增加了6.4%和28.9%。氮沉降对水稻叶绿素a、叶绿素b和叶绿素(a+b)含量均表现为促进作用。乳熟期N1、N2、N3、N4的叶绿素(a+b)比N0增加了34.9%、51.5%、111.3%和143.6%。中高氮处理(N3,N4)对水稻产量的促进作用较为显著,N1、N2、N3、N4的产量分别比N0增加了1.3%、6.2%、13.0%和42.6%。随施氮水平的增加,秕谷率也增加,而产量指数和籽粒大小呈下降趋势。

To study the impact of nitrogen deposition on rice, early rice YUE - YOU 463 seedlings were transplanted in April, 2009 on field conditions （hydromorphic paddy soil）. The experiment started in April and lasted till July. Ammonium nitrate solutions were sprayed on the seedlings every 10 days at four doses during growing season. The simulated elevated N depositions were equivalent to NO （0）, N1 （3 g/（ m2·a）） , N2 （6g,/（m2·a））, N3 （12 g,/（m2·a）） and N4 （24 g/（m2·a）） with three replicates for each treat-ments. The results indicated that N treatments enhanced growth, yield and photosynthesis. The height and the highest photosynthetic rate of N4 increased by 8.9% and 49.5% at tillering stage, 6.4% and 28.9% at mil-king stage. N additions increased Chl a, Chl b and Chl （a ＋ b）. At milking stage, Chl （a ＋ b）in treatments N1, N2, N3, N4 increased by 34.9% ,51.5% ,111.3% and 143.6%, respectively. High N additions increased yield of rice. The yield of N1, N2, N3, N4 increased by 1.3% ,6.2%, 13.0% and 42.6%, respectively. N additions also increased the percentage of non-fully filled grains, decreased harvest index and grain sizes.