不同双季晚稻丰产栽培模式下的氮肥运筹技术研究

Study On Nitrogen Management Technique under Different High Yield Cultivation Models for Double-Season Late Rice

在等氮量条件下,研究抛秧和移栽等栽培方式的氮肥运筹对晚稻生长发育和氮素利用率的影响。研究结果表明:不同栽培方式的氮肥运筹对晚稻茎蘖动态、干物质积累、产量、氮肥农学利用率、氮肥利用率与氮肥运筹方式间存在着一定相关关系,且相关的趋势基本一致。产量、氮肥利用率与氮肥基施比例呈抛物线关系,抛栽当氮肥基施比例为47.61%(南陵)和38.70%(池州),移栽为53.38%时,产量达到最高,氮肥利用率以抛栽当基肥施氮比例为42.97%,移栽为40.88%时,氮肥利用率最高。以目标产量相适宜的施总氮量条件下,抛秧为35～45%、分蘖肥为30%、穗肥为25%-35%,移栽晚稻基肥为45%～55%、分蘖肥为30%、穗肥为15%～25%,利于晚稻干物质积累,可保持较高的分蘖成穗率,使群体发展比较合理,增加抽穗后的物质积累与运转,以及适宜的每穗实粒数和千粒重,从而形成高产以及氮肥利用率的提高。

The effect s of different nitrogen managements and cultivation such as rice seedlings broadcasted and transplanting on the growth of late rice and nitrogen-utilization efficiency under the same nitrogen application condition were conducted. The results showed that nitrogen management were correlated to tiller dynamic, dry matter accumulation, yield, nitrogen agronomic efficiency and nitrogen-utilization efficiency. The relationship between rice yield and nitrogen-utilization efficiency showed a parabolic curve . The highest grain yield was achieved when basal fertilizer accounted for 47.61%（Nanling）and 38.70%（Chizhou） under rice seedlings condition, and that was 53.38% under transplant condition. Meanwhile, the highest nitrogen-utilization efficiency was obtained when basal fertilizer accounted for 42.97% under rice seedlings condition, and that was 40.88% under transplanting condition. In addition, the results also indicated that for an appropriate yield goal, the best nitrogen application ratio is： that the basal fertilizer, tiller fertilizer and panicle fertilizer accounted for 35-45%, 30% and 25-35% under rice seedlings condition respectively,and that was 45-55%, 30% and 15-25% under transplanting condition respectively. This nitrogen management could promote dry matter accumulation, maintain the rate of effective tillers, enhance matter accumulation and translocation after heading, have reasonable population development, and increase the grain number of panicle and one thousand grain weight.