CAJ | 학술논문

秧龄是决定机插稻产量的重要因素，适宜的秧龄是其获取高产的基础。麦（油）稻两熟区，由于茬口安排紧、插秧机械作业繁重、不利天气等因素的影响，常导致机插秧苗未在适宜秧龄期移栽，超秧龄现象普遍存在，对机插稻产量构成威胁。该文旨在阐明长秧龄机插稻对氮素的需求规律和利用效率。试验设置手栽稻为对照，系统研究了长秧龄机插稻生育期、植株氮素需求、吸收、转运的变化规律及其与环境温度间的相关性。结果表明，长秧龄机插稻生育期比手栽稻推迟4～13 d；孕穗至成熟期，中早熟品种氮素需求量小于手栽稻，中晚熟品种则大于手栽稻；孕穗至抽穗期，长秧龄机插稻叶片与茎鞘的氮素输出量、输出率呈下降趋势；抽穗至成熟期，长秧龄机插稻叶片氮素输出量、输出率、转换率升高；成熟期，穗部氮素吸收量降低。典型相关分析表明，稻株氮素需求量、孕穗至抽穗期茎鞘氮素输出量、输出率与有效积温的相关性最密切；叶片氮转换率与平均气温的关联性最紧密。长秧龄机插稻对氮素的吸收利用特性不仅与品种有关，而且与环境温度变化相关，生产中，可依据品种特性，在常规施肥基础上，适当减少中早熟品种长秧龄机插稻穗肥的施用比例，在保证安全齐穗的前提下，适当增大中晚熟品种穗肥的施用比例，采取有效的农艺调控，提高稻株对氮素的吸收利用率，尽量弥补超秧龄所造成的产量损失。该研究可为长秧龄机插水稻的大田氮肥管理提供参考。
앙령시결정궤삽도산량적중요인소，괄의적앙령시기획취고산적기출。맥（유）도량숙구，유우치구안배긴、삽앙궤계작업번중、불리천기등인소적영향，상도치궤삽앙묘미재괄의앙령기이재，초앙령현상보편존재，대궤삽도산량구성위협。해문지재천명장앙령궤삽도대담소적수구규률화이용효솔。시험설치수재도위대조，계통연구료장앙령궤삽도생육기、식주담소수구、흡수、전운적변화규률급기여배경온도간적상관성。결과표명，장앙령궤삽도생육기비수재도추지4～13 d；잉수지성숙기，중조숙품충담소수구량소우수재도，중만숙품충칙대우수재도；잉수지추수기，장앙령궤삽도협편여경초적담소수출량、수출솔정하강추세；추수지성숙기，장앙령궤삽도협편담소수출량、수출솔、전환솔승고；성숙기，수부담소흡수량강저。전형상관분석표명，도주담소수구량、잉수지추수기경초담소수출량、수출솔여유효적온적상관성최밀절；협편담전환솔여평균기온적관련성최긴밀。장앙령궤삽도대담소적흡수이용특성불부여품충유관，이차여배경온도변화상관，생산중，가의거품충특성，재상규시비기출상，괄당감소중조숙품충장앙령궤삽도수비적시용비례，재보증안전제수적전제하，괄당증대중만숙품충수비적시용비례，채취유효적농예조공，제고도주대담소적흡수이용솔，진량미보초앙령소조성적산량손실。해연구가위장앙령궤삽수도적대전담비관리제공삼고。
As an important element determining grain yield, optimum seedling age plays a pivotal role in achieving high grain yield for mechanically transplanted rice. Rice seedlings which grow for a longer time are not suitable for transplanting by machine, and are called “long age seedlings.” However, in wheat-rice rotation regions, rice seedlings are transplanted by machine at long seedling age due to the occurrence of unfavorable factors, such as a late harvest for the previous crop, the limitation of the number of transplanting machines, and the adverse weather, which has severely threatened the machine-transplanting rice yield. The objectives of this paper were to clarify the law of nitrogen demanding and allocation in mechanical transplanted rice with a long seedling age, providing references for rice cultivation under a mechanical transplanting pattern. With conventional artificial transplanting rice as a control, the field experiment was designed to investigate the changeable law for nitrogen requirement, transportation, and allocation in mechanical transplanted rice with a long seedling age. The growth duration of mechanical transplanting rice with a long seedling age was postponed by 4-13 d as compared with artificial transplanted rice. In the case of mid-early maturing cultivars, the amount of nitrogen requirement in mechanical transplanting rice with a long seedling age was less than that in artificial transplanting rice. However, mid-late maturing cultivars had the converse performance. When compared with artificial transplanted rice plants, the nitrogen export amount and rate of leaves and stems tended to dwindle from the booting to the heading stage as well as the nitrogen absorption amount of panicles at the maturity stage, whereas it was the contrary for the nitrogen export amount and rate and conversion rate of leaves from the heading to the maturity stage in mechanically transplanted rice. Canonical correlation analysis indicated that the nitrogen requirement amount of rice plants and nitrogen exportation amount and rate of stems and sheaths were closely related with effective accumulative air temperature, and the nitrogen conversion rate of leaves was intimately correlated with the daily mean air temperature. The characteristics of nitrogen requirement and utilization in mechanically transplanted rice plants with a long seedling age were dominated not only by genotypes but also by environmental temperature. Based on a conventional nitrogen fertilizer application for mechanically transplanted rice, the application ratio of earing fertilizer should be decreased appropriately for mid-early rice cultivars with a long seedling age while it should be enhanced for mid-late cultivars with a long seedling age on the premise of normal maturity. In addition, effective agronomic practices should be adopted to enhance nitrogen usage efficiency of mechanically transplanted rice with a long seedling age, which may gain compensation for the yield loss which resulted from mechanical transplanting at an over-optimum seedling age.