中国生态农业学报2016，Vol.24Issue(5)：572-581,10.DOI:10.13930/j.cnki.cjea.150995
不同施氮水平对返青期水分胁迫下冬油菜补偿效应的影响
Compensative impact of winter oilseed rape (Brassica napus L.) affected by water stress at re-greening stage under different nitrogen rates
摘要
Abstract
Oilseed rape is one of the most important oil crops cultivated on over 6.5 million hectares of land in China. Although mainly cultivated in the Yangtze River Basin, rising winter temperatures in northern China in recent years have made possible to expand the cultivation area of oilseed rape northward and westward. The planting area of winter oilseed rape in Northwest China has increased year by year. Irrigation and nitrogen supply at re-greening stage is important for flower bud differentiation and branch number increase of oilseed rape. However, drought stress is usually frequent at re-greening stage in most regions of Northwest China. Local farmers apply irrigation and nitrogen to oilseed rape fields for high seed yields, but such effect has not been obvious, resulting in various environmental problems. Therefore determining an appropriate nitrogen dose under drought at re-greening stage is important for the production of oilseed rape in Northwest China. Barrel experiments, including 5 nitrogen application rates [0 g (N0), 0.2 g (N1), 0.4 g (N2), 0.6 g (N3) and 0.8 g (N4)] and two water treatments [full water (W, 70%–80%of field water capacity) and deficit water (D, 50%–55%of field water capacity)] at re-greening stage were conducted to measure growth and physiological index, yield components, water use efficiency (WUE) and quality traits of oilseed rape. The study used principal component analysis (PCA) to analyze and evaluate the parameters under different treatments. Results showed that aboveground dry matter, chlorophyll content, photosynthetic rate, seed yield and WUE first increased and then decreased with increasing nitrogen application rate. Then aboveground dry matter, chlorophyll content, photosynthetic rate, seed yield and WUE all reached the maximal level under N3 treatment with the same water conditions. After drought stress and re-watering, shoot dry matter weight, chlorophyll content, photosynthetic rate, yield and yield components of all nitrogen treatments showed certain degree of compensative effect. The compensative effect intensified first and weakened then with N application rate, which was best under N3 treatment. No significant differences were noted in growth indexes, chlorophyll content and seed yield between W and D treatments. Photosynthetic rate under D treatment was significantly higher than that under W treatment with N3. Seed yield reduced by 2.2%and WUE increased by 3.8%in D treatment compared to that of W treatment with N3 nitrogen application. Nitrogen partial factor productivity and seed oil content decreased with increasing nitrogen amount, while seed protein content showed the reverse trend. Compared with N0, average partial factor productivity and seed oil content in N3 treatment decreased by 6.2% and 13.0%, but yield and WUE increased by 87.6%and 32.9%, respectively. Based on PCA for each indicators, we found that the highest PCA score occurred in N3D treatment. Therefore, the N3D treatment was optimized measure for increasing WUE, yield and quality of oilseed rape in northwest China.关键词
冬油菜/返青期/施氮量/水分胁迫/品质/水分利用效率/补偿效应Key words
Winter oilseed rape/Re-greening stage/Nitrogen application rate/Water stress/Seed quality/Water use efficiency/Compensative effect分类
农业科技引用本文复制引用
谷晓博,李援农,杜娅丹,吴国军,周昌明,任全茂,杨丹..不同施氮水平对返青期水分胁迫下冬油菜补偿效应的影响[J].中国生态农业学报,2016,24(5):572-581,10.基金项目
公益性行业(农业)科研专项经费项目(201503105,201503125)和国家高技术研究发展计划(863计划)项目(2011AA100504)资助 （农业）
