College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518060, China.
Sci Rep. 2020 Mar 4;10(1):4047. doi: 10.1038/s41598-020-60695-y.
Haze and cloudy weather reduce photo-synthetically active radiation (PAR), which affects the formation of crop yield and nitrogen (N) fertilizer utilization.. We conducted field trails in normal year and severe winter haze year, aiming to compare the difference of photosynthesis and N uptake in winter rapeseed under different N levels. Daily sunshine hours and averaged radiation intensity in winter haze year decreased by 54.1% and 33.3% respectively as compared with the past 30 years. Diurnal variation of net photosynthetic rate in winter haze day was 16.2% lower than that of sunny day. Leaf area and photosynthetic capacity decreased significantly during winter haze year. The shoot biomass and N uptake at the rosette stage accounted for only 9.6% and 26.6% of the total growth period in winter haze year, while 24.4% and 70.5% in normal year, respectively. However, in winter haze year, as the top dressing of N application increasing after the rosette stage, shoot biomass increased gradually. In order to achieve the target yield of 2.5 t ha, after suffering winter haze, it is necessary to apply additional 73.1 kg N ha. In conclusion, the haze climate reduced the radiation intensity and stability, leading to a decline in photosynthetic productivity in winter oilseed rape. Applying higher N fertilizer after winter haze can compensate the negative influence and ensure rapeseed yield.
阴霾和多云天气会降低光合有效辐射 (PAR)，从而影响作物产量的形成和氮肥 (N) 的利用。...... 我们在正常年和严重冬季霾年进行了田间试验，旨在比较不同氮水平下冬油菜在不同氮水平下光合作用和氮吸收的差异。与过去 30 年相比，冬季霾年的日日照时间和平均辐射强度分别减少了 54.1%和 33.3%。冬季霾天的净光合速率日变化比晴天低 16.2%。冬季霾年叶片面积和光合能力明显下降。在冬季霾年，油菜的茎生物量和氮吸收量仅分别占整个生育期的 9.6%和 26.6%，而在正常年分别为 24.4%和 70.5%。然而，在冬季霾年，由于在莲座期后追施氮肥，茎生物量逐渐增加。为了达到 2.5 吨/公顷的目标产量，在遭受冬季霾后，需要额外施氮 73.1 千克/公顷。总之，霾气候降低了辐射强度和稳定性，导致冬油菜的光合生产力下降。在冬季霾后施用较高的氮肥可以补偿负面影响并确保油菜产量。
