不同缓控释肥搭配脲铵对水稻产量、氮素利用效率和土壤养分的影响

为了明确不同类型缓控释肥搭配脲铵在水稻减氮和节本增效方面的应用效果,特开展田间试验,以嘉兴地区常规施肥(N 225 kg·hm-2)为对照(CK),研究了分别基于木质素类缓控释肥好乐耕(HL)、脲甲醛类缓控释肥永笑(YX)、硝化抑制剂类缓控释肥开擂喽(KL)与脲铵搭配的一基一追模式,在较CK减氮0、20％、35％和50...

Effect of different controlled-release fertilizers with urea ammonium on yield,nitrogen use efficiency and soil nutrients of rice

In the present study, a field experiment was conducted to study the effect of different controlled-release fertilizers (CRFs) with urea ammonium (AU) on the yield, nitrogen use efficiency (NUE) and soil nutrients. The conventional fertilization method (N 225 kg·hm^-2) was introduced as CK, and three CRFs, namely, lignin-based CRF Haolegeng (HL), urea formaldehyde-based CRF Yongxiao (YX), and nitrification inhibitor-based CRF Kaileilou (KL), were selected to form three CRF+AU modes (HL+AU, YX+AU, and KL+AU), and the N input in these modes was reduced by 0, 20%, 35% and 50% as compared with CK, respectively. It was shown that there was no significant difference in yield within the treatments of CRF+AU modes with 20% N reduction and CK. However, when N reduction rate was 35% and 50%, the yields of rice under CRF+AU modes decreased significantly (P<0.05), which could be attributed to greater ratio of decreases in panicles per unit area and grains per panicle compared to seed-setting rate and 1 000-grain weight. The NUE increased with the reduction of N input under CRF+AU modes. When N reduction rate was 50%, NUE was the highest (20.1 kg·kg^-1) under KL+AU modes, and its grain physiological N-use efficiency (PE-grain) was significantly (P<0.05) increased by 14.7% than CK. When N reduction rate was 20% under YX+AU modes, the nitrogen uptake efficiency (NupE) and apparent N recovery efficiency (ANR) were significantly (P<0.05) increased by 12.4% and 22.3%, respectively, as compared with CK. Under CRF+AU modes, with the higher N reduction rate, the contents of soil alkali hydrolyzable N showed decreasing trends. However, the content of soil alkali hydrolyzable N was significantly (P<0.05) increased by 7.44%-9.57% than CK under CRR+AU modes without N reduction. Compared with CK, the soil pH under KL+AU was significantly (P<0.05) reduced by 0.17-0.31 pH unit. Based on the results of grain yield, NUE, ANR and soil nutrients, it was more reasonable to reduce N by 20% than CK under CRF+AU modes, and YX+AU had the best effect among them.