Abstract: In order to explore the high-yield cultivation techniques of oat in saline alkali land of coastal areas in Jiangsu Province, Baiyan3 was as material. The effects of nitrogen application rate (N1=180 kg·hm^-2, N2=270 kg·hm^-2 and N3=360 kg·hm^-2) and planting density (D1=120 kg·hm^-2, D2=180 kg·hm^-2 and D3=240 kg·hm^-2) on growth, physiological characteristics and yield of oat were studied. The results showed that the plant heights were increased first and then decreased with the increase of nitrogen rate during the whole growth period of oat, and the plant heights were increased significantly with the increase of planting density except maturity stage. Compared with low density (D1) and low nitrogen rate (N1), the increases of nitrogen rate and planting density were beneficial to increase biomass. The contents of chlorophyll a and chlorophyll b, and the activities of CAT, POD and SOD were decreased with the increase of density. Under same density, medium nitrogen (N2) and high nitrogen rate (D3) were most conducive to the accumulation of chlorophyll and the activities of CAT, POD and SOD. The effects of nitrogen rate and density on panicle length, panicle number and grain number per panicle were extremely significant, but not significant on 1 000-grain weight. In this study, the grain yield of oat in D3N3 treatment was highest with 4.90×103 kg·hm^-2. In conclusion, the cultivation measures, such as reasonable dense planting and increasing nitrogen fertilizer, could promote synthesis of chlorophyll, enhance photosynthetic efficiency, improve the activities of antioxidant enzymes and resistance, increase biomass and yield of oat in salt-alkali land of coastal shoal, which was great significance to alleviate the shortage of forage grass in the coastal saline-alkali land of Jiangsu Province and improvement of saline-alkali land.

Key words: oat, saline soil, high yield, nitrogen rate, planting density, physiological basis

摘要： 为探究盐碱地燕麦高产栽培技术，在江苏沿海滩涂盐碱地，以白燕3号为试验材料，研究施氮量（N1=180 kg·hm^-2、N2=270 kg·hm^-2、N3=360 kg·hm^-2）和种植密度（D1=120 kg·hm^-2、D2=180 kg·hm^-2、D3=240 kg·hm^-2）对燕麦生长、生理特性及产量的影响。结果表明，全生育期燕麦的株高随施氮量的增加呈先增加后降低的趋势；除成熟期外，加大种植密度显著增加了燕麦株高。与低密度（D1）和低施氮量（N1）处理相比，增加氮肥施用量和种植密度有利于燕麦生物量的积累。然而，叶片中叶绿素a和叶绿素b含量及过氧化氢酶（CAT）、过氧化物酶（POD）和超氧化物歧化酶（SOD）活性均随种植密度的增加而降低。相同种植密度条件下，中、高氮水平（N2和D3）有利于叶片叶绿素的合成及CAT、POD和SOD活性的提高。此外，施氮量和种植密度对穗长、穗数和穗粒数有极显著影响，但对千粒重无显著影响。不同处理的产量表明，高密高氮处理（D3N3）的籽粒产量最高，达4.90×103 kg·hm^-2。由此可见，在沿海滩涂盐碱地采用合理密植、增施氮肥等栽培措施，可促进叶绿素合成、增强叶片光合效率、提高保护酶活性、增加生物产量，最终改良燕麦的抗逆性，提高产量,对缓解江苏沿海滩涂盐碱地畜牧业饲草短缺、改良和开发利用盐碱地具有重要意义。

关键词: 燕麦, 盐碱地, 高产, 氮肥梯度, 栽培密度, 生理基础