不同施肥条件下冬小麦氮素吸收、转运及累积的研究

为给陕西关中地区冬小麦合理施用氮肥提供理论基础,以小偃22为材料,通过田间试验研究了不同施肥条件下冬小麦产量、氮素吸收、转运和累积特点.结果表明,氮磷钾和有机肥配合施用可明显提高小麦籽粒产量,其中在基施有机氮150 kg·hm-2的基础上,施氮量为150～225 kg·hm-2时小麦籽粒产量接近或达到9 000 kg·hm-2的超高产水平,显著高于农民习惯施肥处理(基施纯氮300 kg·hm-2和P2O5 75 kg·hm-2);在不施有机肥、施氮量为270～300 kg·hm-2时,小麦籽粒产量与农民习惯施肥处理差异不明显,说明有机肥具有明显的增产作用.施肥处理时小麦氮素累积有显著影响,氮磷钾配施可显著提高小麦氮素累积量,有机肥和化肥配合施用氮素累积量最高,达到249.3～283.0 kg·hm-2.与农民习惯施肥处理相比,氮磷钾配施条件下小麦生育中期和后期氮素累积量增加,开花后营养器官氮素转运量也随着增加,但施肥处理间氮素转运效率差异不明显.综合来看,陕西关中地区冬小麦在氮磷钾和有机肥配合施用的情况下,氮肥用量应控制在150～225 kg·hm-2.

Study on Nitrogen Uptake, Transformation and Accumulation in Winter Wheat under Different Fertilization

One year field experiment from 2008 to 2009 was conducted to study nitrogen uptake, transformation and accumulation in winter wheat (Xiaoyan 22) under different fertilization, which was aimed to provide a theory for N application of winter wheat in Guanzhong area of Shaanxi Province. The results showed that wheat grain yield increased significantly when nitrogen, phosphorous and potassium were applied with organic fertilizer. When organic N rate was 150 kg·hm^-2 and chemical N rate ranged from 150 to 225 kg·hm^-2, wheat grain yield reached 9000 kg·hm^-2, which was higher than that of conventional fertilization. When N rate was between 270 and 300 kg·hm^-2 without organic fertilizer, the difference of wheat grain yield was not significant compared with conventional fertilization, which indicated that organic fertilizer had great effect on the increase of yield. Fertilization had significant effects on N accumulation. N accumulation amount increased significantly when N, P and K were applied to wheat compared with conventional fertilization. N accumulation amount ranged from 249.3 to 283.0 kg·hm^-2 when N, P and K were incorporated with organic fertilizer. N accumulation amount in the middle and later growth stages and N transformation amount of nutritional organ after anthesis increased when N, P and K were applied to wheat compared with conventional fertilization. In conclusion, in order to get high wheat grain yield, the recommended N application rate in Guanzhong area of Shaanxi province was from 150 to 225 kg·hm^-2, which should be applied with P, K and organic fertilizer.