本试验探讨了7种不同类型缓控释肥一次性施用对水稻产量及群体特征的影响。在研究肥料氮素（N）释放特征的基础上，于2018和2019年进行盆栽试验，以常规分次施肥（CK，基穗比为1:1）为对照，对水稻叶片SPAD值、产量及其构成、茎蘖动态和干物质积累进行研究。结果表明：不同类型缓控释肥的氮素释放特征差异显著。树脂包衣尿素（PCU）表现为控释模式，整个生育期持续释放氮素；硫包衣尿素（SCU）表现为缓释模式，中后期氮素释放不足；脲酶抑制剂尿素（AHA）和脲甲醛（UF）表现为速释模式，前期爆发性释放，中后期无释放，但其供肥能力可持续到抽穗期。PCU延缓了高峰苗期，与CK相比，干物质积累、叶片SPAD值无显著差异，同时由于整个生育阶段氮素的持续释放，每穗粒数、结实率和千粒重增加，从而提高水稻产量；SCU由于后期氮供应不足，总颖花量低，水稻产量降低，但差异不显著；AHA和UF易受环境因素的影响，对产量的影响不一致。本试验结果表明，在盆栽等量施氮条件下，供肥能力强、有效持续时间长的肥料类型更有利于水稻后期干物质积累，提高产量。

To optimize both grain yield and quality of low-glutelin rice cultivars under N-fertilizer strategies, two-year field experiments involving three low-glutelin rice cultivars (W1240, W1721, W025) and an ordinary rice cultivar (H9405) with five N treatments were carried out to determine the effects of N application rate and genotype on protein fractions contents and Glutelin/Prolamin ratio (Glu/Pro). The difference of protein fraction concentrations affected by N application rate existed in genotypes. Ordinary rice cultivar had a larger increase in glutlein concentration affected by N application rate than low-glutelin rice cultivars did. Glutelin in H9405 had a increase of 30.6 and 41.0% under the N4 treatment (360 kg N ha–1) when compared with N0 treatment (no fertilizer N) in 2010 and 2011 respectively, while all the low-glutelin rice cultivars showed relatively smaller increases for two years. Variance analysis showed no significant effect of N application rate on glutelin in W1240 and W025 while the effects on albumin, globulin and prolamin were significant in low-glutelin rice. What’s more, N treatment had no significant influence on Glu/Pro ratios in low-glutelin rice cultivars while a significant increase in Glu/Pro ratio was observed in ordinary rice cultivar. So low-gultelin rice cultivars showed a different pattern from ordinary rice cultivars when influenced by N application rate.

The objective of this study was to determine the morphology mechanism of nitrogen (N) fertilizer rates and ratio on lodging resistance through analying its effects among lodging index (LI), lodging-related morphological traits and physical strength in basal internodes by comparing japonica and indica super rice cultivars. Field experiments, with three nitrogen levels (0, 150 and 300 kg ha-1) and two ratios of basal to topdressing (8:2 and 5:5) with two super rice cultivars (Yliangyou 2 and Wuyunjing 23), were conducted in the Baolin Farm, Danyang Country, Jiangsu Province, China, in 2011 and 2012. Effects of N fertilizer rates and ratios on morphology of whole plant, morphology traits in basal internodes and culm’s physical strength parameters were investigated at 20 d after full heading stage. LI of Yliangyou 2 was significant greater than that of Wuyunjing 23 due to larger bending moment by whole plant (WP) with higher plant height and gravity center height. With higher volume of N fertilizer, LI of two super rice cultivars was increased conspicuously. However, no significant effect was detected with increase of panicle fertilizer ratio. The size of breaking strength (M) in basal internodes was the key factor determining LI among N fertilizer treatments. Correlation analysis revealed that M value was positively related bending stress (BS) of Wuyunjing 23 and section modulus (Z) of Yliangyou 2, respectively. The higher N fertilizer levels induced reduction of BS of Wuyunjing 23 due to weak culm and leaf sheath plumpness status and reduced Z of Yliangyou 2 owning to small diameter and culm wall thickness, consequently, influencing their M indirectly. These results suggested that breaking strength was the key factor influencing LI with increase of N fertilizer levels. However, the lodging-related morphology mechanism was different with genotypes. Culm wall thickness and diameter in basal internodes of indica super rice and culm and leaf sheath plumpness status of japonica super rice influenced breaking strength, as well as lodging index, respectively.