油菜氮肥的轻简施用技术

摘要

Simplified N fertilizer application technique was studied to investigate the effects on rapeseed yield under direct sowing system and transplanting system. The technique included suitable application method, nitrogen rate and slow release proportion. Results indicated that slow release N fertilizer led to higher yield than common N in one -time application, especially under transplanting system. The N rates for the highest yield reached 245.9 kg/hm2 of common N and 242. 2kg/hm2 of slow release N for rapeseed sown directly, while it only reached 225. 0 kg/hm2 and 239. 6kg/hm2 respectively for transplanting ones. High proportion of slow release N improved more growth and N use efficiency under direct sowing, and the suitable proportion was 78.85% to 80. 83% , while it was 25.00% for transplanting ones. Results also showed that the yield for strip direct sowing rapeseed and spot transplanting rapeseed were the highest with one -time application, then followed by broadcast and flip rapeseed. The lowest yield were from rapeseed with broadcasted fertilizers. Under the same fertilizer rates, the number of N applications increased the yield for direct sowing rapeseed. It showed the same trend in transplanting system. In summary , suitable N application method could be selected according to labor condition, mechanization degree, economic level and planting customs in different product areas. In one - time application, more N rates with common N or less slow release N were needed for high yield. For direct sowing rapeseed, higher proportions of slow release N could improve both yield and N efficiency.%研究了油菜氮肥的轻简施用技术,包括适宜的施用方式、用量和缓释比例(即缓释氮肥用量占总氮肥用量的比例),及其在直播和移栽油菜间的差异.结果表明,试验条件下,一次性施用缓释氮肥产量高于常规氮肥,且移栽油菜产量高于直播油菜；常规氮肥和缓释氮肥的最佳产量的施氮量,直播油菜分别是245.9和242.2kg/hm2,而移栽油菜分别只需225.0和239.6kg/hm2；高比例缓释氮肥更有利于直播油菜生长和氮肥利用效率提高,直播油菜氮肥最佳缓释比例为78.8％～ 80.8％,移栽油菜氮肥最佳缓释比例为25.0％.试验还表明,一次性施氮条件下,条施处理或穴施处理的油菜产量最高,撒施翻盖处理次之,撒施处理效果最差；在同等施肥水平下,增加氮肥的施用次数可以提高直播油菜的产量,对移栽油菜也表现相似的结果.分析认为,不同油菜产区可以根据劳动力状况、机械化水平、经济条件和习惯种植模式等选择适宜的氮肥轻简施用技术；一次性施氮条件下,选用普通氮肥可以适度增加用量以获得传统多次施肥的产量,选用缓释氮肥用量可以适当降低；对直播油菜而言,可以施用更高比例缓释氮肥以达到增加产量和氮肥利用效率的目的.