Abstract:

【Objective】 This experiment was conducted to clarify the effects of application methods of mixed controlled-release nitrogen fertilizer on the yield and nitrogen utilization of good-eating quality japonica rice under different mechanical transplanting methods in Huaibei region, aiming to screen the optimal mixed controlled-release nitrogen fertilizer treatment that matches the nutrient absorption of good-eating quality japonica rice, and to provide a scientific basis for its high-yield, high-quality and simplified cultivation.【Method】 In this experiment, two good-eating quality japonica rice varieties, Xudao 9 and Nanjing 5718, were used as materials to study the effects on yield, population quality indices and characteristics of nitrogen absorption and utilization under different treatments. Controlled-release fertilizer and quick-acting nitrogen fertilizer were mixed at a ratio of 5:5. The controlled-release fertilizer was blended from fertilizers with four different release periods (40, 60, 80, and 100 d) at a ratio of 1:4 to form three mixing modes, designated as N1 (40+60), N2 (40+80), and N3 (40+100). Conventional urea split application (CK) was used as a control. 【Result】 (1) Under different mechanical transplanting methods, the N2 treatment achieved the highest yield. The increase in yield was mainly attributed to the significant increase in effective panicle number and total spikelet number. Under the wide-narrow row pot seedling mechanical transplanting method, the average yields of the N2 treatment over two years reached 11.29 t hm⁻² and 11.79 t hm⁻², showing significant increases of 6.01% and 6.89% compared with CK, respectively. Under the equal-row spacing blanket seedling mechanical transplanting method, the average yields of the N2 treatment over two years reached 10.71 t hm⁻² and 11.12 t hm⁻², showing significant increases of 5.05% and 5.30% compared with CK, respectively. (2) Under different mechanical transplanting methods, the average tiller number at maturity in the N2 treatment was significantly increased by 7.30%−10.44% compared with CK, which effectively promoted the formation of high-yield populations. Meanwhile, under the N2 treatment, the leaf area index and leaf photosynthetic potential during the heading-maturity stage were significantly increased by 3.47%−13.25% and 6.53%−7.77% compared with CK, respectively, effectively promoting the formation of high-photosynthetic-efficiency populations. (3) Under different transplanting methods, the partial factor productivity of applied nitrogen and the agronomic nitrogen use efficiency showed the order of N2 > N3 > CK > N1, while the nitrogen uptake efficiency and the nitrogen uptake per 100 kilograms of grain showed the order of N3 > N2 > CK > N1. In the N2 treatment, the partial factor productivity of applied nitrogen, agronomic nitrogen use efficiency, nitrogen uptake efficiency and nitrogen uptake per 100 kilograms of grain were 5.13%−6.44%, 12.74%-16.14%, 15.14%-16.62% and 2.35%-2.87% higher than those in CK, respectively. The higher nitrogen utilization rate led to greater dry matter accumulation in the population under the N2 treatment. Under the wide-narrow row pot seedling mechanical transplanting method, the average dry matter accumulation during the jointing-heading stage and the heading-maturity stage in the N2 treatment was higher than that in CK by 3.11% and 3.23%, and 6.85% and 11.62%, respectively, over the two years; under the equal-row spacing blanket seedling mechanical transplanting method, the average dry matter accumulation during the jointing-heading stage and the heading-maturity stage in the N2 treatment was higher than that in CK by 2.80% and 2.45%, and 5.61% and 9.23%, respectively, over the two years. 【Conclusion】 Under both wide-narrow row pot seedling mechanical transplanting and equal-row spacing blanket seedling mechanical transplanting methods, the one-time basal application of the N2 mixed controlled-release fertilizer best matched the nutrient absorption of good-eating quality japonica rice in the Huaibei region. It promoted the formation of high-yield and high-efficiency populations, and thus can be regarded as an effective measure for achieving increased yield and efficiency through simplified cultivation of good-eating quality japonica rice in the Huaibei region.

Key words: good taste quality japonica rice, mechanical transplanting, controlled-release fertilizer, yield, nitrogen utilization

摘要：

【目的】明确不同机插方式下，控混肥施用方式对淮北地区优质食味粳稻产量及氮素利用影响。以期筛选与优质食味粳稻养分吸收相匹配的最优控混肥处理，为优质食味粳稻丰产优质轻简化栽培提供依据。【方法】以优质食味粳稻品种徐稻9号、南粳5718为材料，设置宽窄行钵苗机插和等行距毯苗机插2种机插方式，配套3种控混肥配比，研究了不同处理下产量、群体质量指标及氮素吸收利用等方面差异。控混肥以缓控释氮肥与速效氮肥按5:5的比例混合，其中缓控释肥由4种不同释放期(40、60、80、和100 d)肥料按照1∶4的比例混合形成3种配比方式，分别为40 d+60 d、40 d+80 d、40 d +100 d，同时设置常规分次施肥(CK)为对照。【结果】1）不同机插方式下均为N2处理产量最高，N2处理产量的提升主要得益于有效穗数和群体颖花量的显著增加。宽窄行钵苗机插方式下，N2处理两年平均产量分别达11.29 t hm⁻²、11.79 t hm⁻²，较CK分别显著增产6.01%、6.89%；等行距毯苗机插方式下，N2处理两年平均产量分别达10.71 t hm⁻²、11.12 t hm⁻²，较CK分别显著增产5.05%、5.30%。（2）不同机插方式下，N2处理成熟期平均茎蘖数较CK显著增加7.30%~10.44%，有效促进高产群体形成；同时，N2处理下抽穗-成熟期叶面积指数、叶片光合势均较CK显著提升，分别达3.47%~13.25%、6.53%~7.77%，有效促进了高光效群体构建。（3）不同机插方式下，氮肥偏生产力和氮肥农学利用率表现为N2>N3>CK>N1，而氮素吸收利用率和百千克籽粒吸氮量则表现为N3>N2>CK>N1。N2处理下氮肥偏生产力、氮肥农学利用率、氮肥吸收利用率和百千克籽粒吸氮量分别较CK高5.13%~6.44%、12.74%~16.14%、15.14%~16.62%和2.35%~2.87%。较高的氮素利用率使得N2处理下群体获得更多的干物质积累量。宽窄行钵苗机插方式下，N2处理两年平均拔节至抽穗和抽穗至成熟阶段干物质积累量较CK分别高3.11%、3.23%和6.85%、11.62%；等行距毯苗机插方式下，N2处理两年平均拔节至抽穗和抽穗至成熟阶段干物质积累量较CK分别高2.80%、2.45%和5.61%、9.23%。【结论】宽窄行钵苗机插和等行距毯苗机插方式下40 d+80 d(N2)处理控混肥一次性基施配方与淮北地区优质食味粳稻养分吸收最为匹配，促进了高产高效群体的形成，可以作为淮北地区优质食味粳稻实现增产增效轻简化栽培的有效措施。

关键词: 优质食味粳稻, 机插, 控释肥, 产量, 氮素利用