Abstract:

【Objective】Nitrogen uptake and utilization decide matter accumulation and yield formation of rice. With the shrinking rural labor force and rapid development of machine-transplanting, there were few studies yet on nitrogen uptake under the integration of rice seedling nursing for mechanical transplanting and transplanting machines. In this manuscript, focusing on seedling raising-mechanical transplanting, a key link that connects agricultural machines with agricultural practices, we explored the effects of seedling raising methods and transplanting machines on nitrogen absorption and utilization of mechanically transplanted rice.【Method】Hybrid indica rice F you 498 was used as test material and a three-factor random block experiment was designed(two seedling raising methods: nutrient soil and slime; three seeding amount: 65, 85 and 105 g/plate; two transplanting machines: 4- row walk-on transplanter and 6-row riding high-speed transplanter). 【Result】The seedling raising method, seed quantity and transplanting machine exerted significant or extremely significant effects on nitrogen absorption and translocation in vegetative organs, SPAD value of flag leaf and nitrogen harvest index, nitrogen production efficiency and grain yield of mechanically transplanted rice, and the interaction effect was significant or extremely significant. The nitrogen accumulation and nitrogen use efficiency of mechanically transplanted rice under nutrient soil treatment were higher than those under slime treatment, and the nitrogen translocation amount, translocation rate, contribution rate and nitrogen increase in panicle were higher than those under slurry treatment to a certain extent, with an average increase of 21.12%, 15.20%, 10.03% and 6.45%. With the increasing sowing quantity, the grain yield, nitrogen absorption and translocation amount, nitrogen dry matter production efficiency and nitrogen partial productivity of mechanically transplanted rice increased first and then decreased. Especially, the nitrogen accumulation in mature stage of mechanically transplanted rice with the sowing quantity of 85 g/plate increased by 16.19% and 28.14% on average as compared with the sowing amount of 65 g/plate and 105 g/plate. The yield and its component factors, dry matter weight at seeding stage, nitrogen uptake and translocation amount, nitrogen dry matter production efficiency and nitrogen partial productivity of mechanically transplanted rice with 6-row riding high-speed transplanter were significantly higher than those with 4-row walk-on transplanter.【Conclusion】Given nitrogen accumulation, nitrogen translocation amount, nitrogen accumulation in panicle, nitrogen yield and its components, nutrition soil , coupled with the sowing quantity of 85 g/plate and 6-row riding high-speed transplanter could effectively improve nitrogen uptake and utilization and promote the formation of grain yield.

Key words: seedling raising method, seeding amount, transplanting machine, N absorption and utilization, yield

摘要：

【目的】氮素的吸收利用决定着水稻物质积累和产量的形成。随着农村劳动力的减少,机插稻迅速发展, 但针对机插稻育秧环节与插秧机具融合对机插稻氮素吸收利用特征影响的研究较少。以机插稻农机农艺首要融合点“育秧-机插”关键环节为研究对象,探究育秧方式配合不同插秧机具对机插稻氮素吸收利用的影响。【方法】以杂交籼稻F优498为试验材料,采用三因素随机区组试验,设置2种育秧方式：营养土育秧和稀泥育秧;3个播种量：65 g/盘,85 g/盘,105 g/盘;2种插秧机具：4行手扶式插秧机,6行乘坐式高速插秧机。【结果】育秧方式、播种量以及插秧机具对机插稻结实期不同营养器官氮素吸收转运、剑叶SPAD值以及氮素收获指数、氮素稻谷生产效率与产量影响显著或极显著,且互作效应显著或极显著。营养土育秧处理下机插稻氮素积累以及氮素利用效率较稀泥育秧优势明显,植株各器官氮素转运量、转运率、贡献率以及穗部氮素增加量均一定程度高于稀泥育秧处理,平均提高了21.12%、15.20%、10.03%、6.45%;随着播种量的增加,机插稻稻谷产量、结实期氮素吸收转运量、氮素干物质生产效率以及氮肥偏生产力呈先上升后下降的趋势,尤其播种量为85 g/盘时机插稻成熟期植株中氮素的积累量相较于65 g/盘、105 g/盘播量平均增加了16.19%,28.14%;6行乘坐式高速插秧机处理下机插稻产量以及构成因素、结实期干物质量、植株氮素吸收量和转运量、氮干物质生产效率以及氮肥偏生产力显著高于4行手扶式插秧机。【结论】综合氮素积累量和氮素转运量、机插稻结实期穗部氮素积累量、产量及其构成因素考虑,运用营养土育秧,播量85 g/盘配合6行乘坐式高速插秧机能有效提高机插稻氮素吸收利用,促进产量的形成。

关键词: 育秧方式, 播种量, 插秧机具, 氮素吸收利用, 产量