Effects of Interaction Between Nitrogen Application Rate and Direct-sowing Density on Yield Formation Characteristics of Rice

doi:10.16819/j.1001-7216.2019.8112

Abstract

Abstract:

【Objective】To reveal the effects of interaction between nitrogen application rate and direct-sowing density on yield formation characteristics of rice, 【Method】 Nanjing 9108, a japonica cultivar with good taste, was used as the experimental material. We designed four nitrogen application rates, namely N₁(0 kg/hm²), N₂(150 kg/hm²), N₃(225 kg/hm²), N₄(300 kg/hm²), and five direct-sowing densities, namely D₁(90×10⁴/hm²), D₂(180×10⁴/hm²), D₃(270×10⁴/hm²), D₄(360×10⁴/hm²), D₅(450×10⁴/hm²). 【Result】The rice yield increased with the increase of nitrogen rate. Under the nitrogen application rate of N₁, N₂, N₃, the grain yield of rice was first increased and then decreased with the increase of direct-sowing density. Under these nitrogen application rates, the highest yield was 6.74 t/hm², 7.78 t/hm², 8.93 t/hm², respectively, which was obtained at the direct-sowing densities of D₄, D₃, D₂. Under the nitrogen rate of N₄, the yield decreased with the increase of direct-sowing density, and the highest yield was 9.55 t/hm², which was obtained at the direct-sowing density of D₁. Appropriate direct-sowing densities under different nitrogen application rates can improve rice yield, among which the yield of N₄D₁ was the highest, due to its moderate number of stems and tillers, large panicle type and LAI in the mid- and late-growth stages, high photosynthetic potential and crop growth rate, superior net assimilation rate and dry matter weight in the later growth. 【Conclusion】Under the high nitrogen rate of 300 kg/hm², mechanical direct-sowing rice can easily achieve high yield, and appropriate direct-sowing density can further improve rice yield. However, given green production and cost saving and efficiency increasing, to reduce the nitrogen rate to 225 kg/hm², and the direct-sowing density to 180×10⁴/hm² can still obtain yield around 9 t/hm², which is also worthy of promotion.

Key words: rice, mechanical direct-sowing, nitrogen application rate, direct-sowing density, yield, photosynthesis and matter production

摘要：

【目的】旨在阐明施氮量和直播密度互作对水稻产量形成特征的影响。【方法】以优质食味粳稻南粳9108为试验材料,设置4个施氮量处理,即N₁(0 kg/hm²)、N₂(150 kg/hm²)、N₃(225 kg/hm²)、N₄(300 kg/hm²),5个直播密度处理,即D₁(90×10⁴/hm²)、D₂(180×10⁴/hm²)、D₃(270×10⁴/hm²)、D₄(360×10⁴/hm²)、D₅(450×10⁴/hm²)。【结果】随施氮量增加,机直播稻产量增加。在N₁、N₂和N₃施氮量下,机直播稻产量随直播密度增加先增后降,分别在D₄、D₃和D₂密度下获得最高产量,其最高产量分别为6.74、7.78和8.93 t/hm²;在N₄施氮量下,水稻产量随直播密度增加而降低,在D₁密度下获得最高产量,为9.55 t/hm²。不同施氮量下采用适宜直播密度可以提高水稻产量,其中N₄施氮量配套D₁直播密度机直播稻产量最高,其有效穗数适宜,穗型较大,生育中后期LAI较大、光合势高,生育后期群体生长率、净同化率和干物质积累量等指标均较优。【结论】机直播稻在300 kg/hm²的高氮水平下易取得高产,配套适宜直播密度可进一步提高水稻产量,但从稻田绿色生产和节本增效角度考虑,机直播稻适当降低施氮量至225 kg/hm²,配套180×10⁴/hm²直播密度仍可获得9 t/hm²左右的产量,也值得推广。

关键词: 水稻, 机械直播, 施氮量, 直播密度, 产量, 光合物质生产

CLC Number:

Pei WU, Tianye CHEN, Jiaqi YUAN, Heng HUANG, Zhipeng XING, Yajie HU, Ming ZHU, Dejian LI, Guolin LIU, Hongcheng ZHANG. Effects of Interaction Between Nitrogen Application Rate and Direct-sowing Density on Yield Formation Characteristics of Rice[J]. Chinese Journal OF Rice Science, 2019, 33(3): 269-281.

吴培, 陈天晔, 袁嘉琦, 黄恒, 邢志鹏, 胡雅杰, 朱明, 李德剑, 刘国林, 张洪程. 施氮量和直播密度互作对水稻产量形成特征的影响[J]. 中国水稻科学, 2019, 33(3): 269-281.

Figures/Tables 9

References 35

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施氮量 Nitrogen application rate	直播密度 Direct-sowing density	播种期 Sowing (Month-Day)	拔节期 Jointing (Month-Day)	抽穗期 Heading (Month-Day)	成熟期 Maturity (Month-Day)	播种-拔节 Sowing- Jointing/d	拔节-抽穗 Jointing- Heading/d	抽穗-成熟 Heading- Maturity/d	总生育期 Total period of duration/d)
N₁	D₁	06-12	08-10	09-01	10-25	59	22	54	135
	D₂	06-12	08-10	09-01	10-25	59	22	54	135
	D₃	06-12	08-10	09-01	10-25	59	22	54	135
	D₄	06-12	08-10	09-01	10-25	59	22	54	135
	D₅	06-12	08-10	09-01	10-25	59	22	54	135
N₂	D₁	06-12	08-10	09-02	10-27	59	23	55	137
	D₂	06-12	08-10	09-02	10-27	59	23	55	137
	D₃	06-12	08-10	09-02	10-27	59	23	55	137
	D₄	06-12	08-10	09-02	10-27	59	23	55	137
	D₅	06-12	08-10	09-02	10-27	59	23	55	137
N₃	D₁	06-12	08-10	09-04	10-30	59	25	56	140
	D₂	06-12	08-10	09-04	10-30	59	25	56	140
	D₃	06-12	08-10	09-04	10-30	59	25	56	140
	D₄	06-12	08-10	09-04	10-30	59	25	56	140
	D₅	06-12	08-10	09-04	10-30	59	25	56	140
N₄	D₁	06-12	08-10	09-05	11-03	59	26	59	144
	D₂	06-12	08-10	09-05	11-03	59	26	59	144
	D₃	06-12	08-10	09-05	11-03	59	26	59	144
	D₄	06-12	08-10	09-05	11-03	59	26	59	144
	D₅	06-12	08-10	09-05	11-03	59	26	59	144

施氮量 Nitrogen application rate	直播密度 Direct-sowing density	播种期 Sowing (Month-Day)	拔节期 Jointing (Month-Day)	抽穗期 Heading (Month-Day)	成熟期 Maturity (Month-Day)	播种-拔节 Sowing- Jointing/d	拔节-抽穗 Jointing- Heading/d	抽穗-成熟 Heading- Maturity/d	总生育期 Total period of duration/d)
N₁	D₁	06-12	08-10	09-01	10-25	59	22	54	135
	D₂	06-12	08-10	09-01	10-25	59	22	54	135
	D₃	06-12	08-10	09-01	10-25	59	22	54	135
	D₄	06-12	08-10	09-01	10-25	59	22	54	135
	D₅	06-12	08-10	09-01	10-25	59	22	54	135
N₂	D₁	06-12	08-10	09-02	10-27	59	23	55	137
	D₂	06-12	08-10	09-02	10-27	59	23	55	137
	D₃	06-12	08-10	09-02	10-27	59	23	55	137
	D₄	06-12	08-10	09-02	10-27	59	23	55	137
	D₅	06-12	08-10	09-02	10-27	59	23	55	137
N₃	D₁	06-12	08-10	09-04	10-30	59	25	56	140
	D₂	06-12	08-10	09-04	10-30	59	25	56	140
	D₃	06-12	08-10	09-04	10-30	59	25	56	140
	D₄	06-12	08-10	09-04	10-30	59	25	56	140
	D₅	06-12	08-10	09-04	10-30	59	25	56	140
N₄	D₁	06-12	08-10	09-05	11-03	59	26	59	144
	D₂	06-12	08-10	09-05	11-03	59	26	59	144
	D₃	06-12	08-10	09-05	11-03	59	26	59	144
	D₄	06-12	08-10	09-05	11-03	59	26	59	144
	D₅	06-12	08-10	09-05	11-03	59	26	59	144

施氮量 Nitrogen application rate	直播密度 Direct-sowing density	有效穗数 Productive panicle number/(×10⁴·hm^-2)	每穗颖花数 Spikelet number per panicle	群体颖花量 Population spikelet number/(×10⁴·hm^-2)	结实率 Seed-setting rate/%	千粒重 1000-grain weight/g	2017年实产 2017 yield /(t·hm^-2)	2016年实产 2016 yield /(t·hm^-2)
N₁	D₁	283.14 j	82.1 ghi	23 249.40 j	96.09 ab	27.32 abc	5.78 k	5.89 l
	D₂	307.45 i	80.3 hij	24 695.30 ij	96.60 ab	27.40 abc	6.17 j	6.27 kl
	D₃	325.82 gh	77.9 ij	25 373.73 ij	96.84 ab	27.65 ab	6.45 ij	6.50 jk
	D₄	342.88 f	76.9 j	26 358.36 i	96.97 a	27.77 a	6.74 i	6.90 ij
	D₅	352.54 ef	71.4 k	25 174.86 ij	96.53 ab	27.64 ab	6.39 ij	6.51 jk
	均值Mean	322.37	77.7	24 970.33	96.61	27.56	6.31	6.42
N₂	D₁	316.68 hi	93.4 de	29 588.39 h	93.53 abc	26.93 abc	7.18 h	7.24 hi
	D₂	346.20 f	89.2 ef	30 865.57 fgh	93.68 abc	26.96 abc	7.44 fgh	7.54 fgh
	D₃	364.92 de	87.8 f	32 024.54 fg	93.88 abc	27.04 abc	7.78 ef	7.80 ef
	D₄	378.09 cd	80.6 hij	30 454.85 gh	94.08 abc	27.38 abc	7.49 fgh	7.61 fgh
	D₅	388.05 bc	77.1 ij	29 915.10 gh	94.74 abc	27.17 abc	7.30 gh	7.33 gh
	均值Mean	358.79	85.6	30 569.69	93.98	27.10	7.44	7.50
N₃	D₁	338.37 fg	108.0 b	36 526.07 cd	92.09 abc	26.48 abc	8.53 c	8.61 cd
	D₂	368.43 de	101.9 c	37 559.49 bc	93.35 abc	26.57 abc	8.93 b	8.99 bc
	D₃	381.60 cd	93.3 de	35 594.16 cd	93.49 abc	26.84 abc	8.47 c	8.54 d
	D₄	391.59 abc	84.4 fgh	33 058.59 ef	93.52 abc	26.75 abc	8.05 de	8.20 de
	D₅	398.60 ab	79.0 ij	31 488.32 fgh	93.21 abc	26.90 abc	7.59 fg	7.72 fg
	均值Mean	375.72	93.3	34 845.33	93.13	26.71	8.32	8.41
N₄	D₁	354.90 ef	115.4 a	40 968.00 a	91.09 c	26.02 c	9.55 a	9.72 a
	D₂	380.64 cd	104.2 bc	39 652.43 ab	91.92 bc	26.08 c	9.33 a	9.40 ab
	D₃	394.53 abc	94.7 d	37 351.11 c	92.69 abc	26.29 bc	8.94 b	8.99 bc
	D₄	402.48 ab	86.7 fg	34 885.22 de	92.96 abc	26.44 abc	8.38 cd	8.44 d
	D₅	407.94 a	80.7 hij	32 913.54 ef	92.49 abc	26.14 c	7.70 ef	7.76 f
	均值Mean	388.10	96.3	37 154.06	92.23	26.20	8.78	8.86
方差分析 Variance analysis	N	**	**	**	ns	ns	**	**
	D	**	**	**	ns	ns	**	**
	N×D	ns	**	**	ns	ns	**	**

施氮量 Nitrogen application rate	直播密度 Direct-sowing density	有效穗数 Productive panicle number/(×10⁴·hm^-2)	每穗颖花数 Spikelet number per panicle	群体颖花量 Population spikelet number/(×10⁴·hm^-2)	结实率 Seed-setting rate/%	千粒重 1000-grain weight/g	2017年实产 2017 yield /(t·hm^-2)	2016年实产 2016 yield /(t·hm^-2)
N₁	D₁	283.14 j	82.1 ghi	23 249.40 j	96.09 ab	27.32 abc	5.78 k	5.89 l
	D₂	307.45 i	80.3 hij	24 695.30 ij	96.60 ab	27.40 abc	6.17 j	6.27 kl
	D₃	325.82 gh	77.9 ij	25 373.73 ij	96.84 ab	27.65 ab	6.45 ij	6.50 jk
	D₄	342.88 f	76.9 j	26 358.36 i	96.97 a	27.77 a	6.74 i	6.90 ij
	D₅	352.54 ef	71.4 k	25 174.86 ij	96.53 ab	27.64 ab	6.39 ij	6.51 jk
	均值Mean	322.37	77.7	24 970.33	96.61	27.56	6.31	6.42
N₂	D₁	316.68 hi	93.4 de	29 588.39 h	93.53 abc	26.93 abc	7.18 h	7.24 hi
	D₂	346.20 f	89.2 ef	30 865.57 fgh	93.68 abc	26.96 abc	7.44 fgh	7.54 fgh
	D₃	364.92 de	87.8 f	32 024.54 fg	93.88 abc	27.04 abc	7.78 ef	7.80 ef
	D₄	378.09 cd	80.6 hij	30 454.85 gh	94.08 abc	27.38 abc	7.49 fgh	7.61 fgh
	D₅	388.05 bc	77.1 ij	29 915.10 gh	94.74 abc	27.17 abc	7.30 gh	7.33 gh
	均值Mean	358.79	85.6	30 569.69	93.98	27.10	7.44	7.50
N₃	D₁	338.37 fg	108.0 b	36 526.07 cd	92.09 abc	26.48 abc	8.53 c	8.61 cd
	D₂	368.43 de	101.9 c	37 559.49 bc	93.35 abc	26.57 abc	8.93 b	8.99 bc
	D₃	381.60 cd	93.3 de	35 594.16 cd	93.49 abc	26.84 abc	8.47 c	8.54 d
	D₄	391.59 abc	84.4 fgh	33 058.59 ef	93.52 abc	26.75 abc	8.05 de	8.20 de
	D₅	398.60 ab	79.0 ij	31 488.32 fgh	93.21 abc	26.90 abc	7.59 fg	7.72 fg
	均值Mean	375.72	93.3	34 845.33	93.13	26.71	8.32	8.41
N₄	D₁	354.90 ef	115.4 a	40 968.00 a	91.09 c	26.02 c	9.55 a	9.72 a
	D₂	380.64 cd	104.2 bc	39 652.43 ab	91.92 bc	26.08 c	9.33 a	9.40 ab
	D₃	394.53 abc	94.7 d	37 351.11 c	92.69 abc	26.29 bc	8.94 b	8.99 bc
	D₄	402.48 ab	86.7 fg	34 885.22 de	92.96 abc	26.44 abc	8.38 cd	8.44 d
	D₅	407.94 a	80.7 hij	32 913.54 ef	92.49 abc	26.14 c	7.70 ef	7.76 f
	均值Mean	388.10	96.3	37 154.06	92.23	26.20	8.78	8.86
方差分析 Variance analysis	N	**	**	**	ns	ns	**	**
	D	**	**	**	ns	ns	**	**
	N×D	ns	**	**	ns	ns	**	**

施氮量 Nitrogen application rate	产量构成因素 Yield components	产量构成因素间相关系数 Correlation coefficient among yield components					对Y效应 Effect on Y (P_i-Y)	对X₃效应 Effect on X₃ (P_i-X₃)
施氮量 Nitrogen application rate	产量构成因素 Yield components	X₂	X₃	X₄	X₅	Y(Yield)	对Y效应 Effect on Y (P_i-Y)	对X₃效应 Effect on X₃ (P_i-X₃)
N₁	有效穗数Productive panicle number (X₁)	-0.920*	0.850	0.697	0.898*	0.866		2.081
	每穗颖花数Spikelet number per panicle (X₂)		-0.575	-0.375	-0.696	-0.602		1.339
	群体颖花量Population spikelet number (X₃)			0.957*	0.936*	0.997**	0.759
	结实率Seed-setting rate (X₄)				0.847	0.945*	0.027
	千粒重1000-grain weight (X₅)					0.960**	0.227
N₂	有效穗数 Productive panicle number (X₁)	-0.942*	0.234	0.867	0.770	0.391		2.951
	每穗颖花数Spikelet number per panicle (X₂)		0.105	-0.940*	-0.812	-0.064		2.885
	群体颖花量Population spikelet number (X₃)			-0.168	-0.057	0.971**	0.983
	结实率Seed-setting rate (X₄)				0.593	-0.038	-0.008
	千粒重1000-grain weight (X₅)					0.167	0.228
N₃	有效穗数Productive panicle number (X₁)	-0.948*	-0.769	0.837	0.906*	-0.663		1.146
	每穗颖花数Spikelet number per panicle (X₂)		0.932*	-0.630	-0.897*	0.864		2.019
	群体颖花量Population spikelet number (X₃)			-0.309	-0.770	0.984**	0.926
	结实率Seed-setting rate (X₄)				0.674	-0.154	0.251
	千粒重1000-grain weight (X₅)					-0.721	-0.176
N₄	有效穗数Productive panicle number (X₁)	-0.981**	-0.927*	0.932*	0.671	-0.880*		0.968
	每穗颖花数Spikelet number per panicle (X₂)		0.982**	-0.877	-0.626	0.953*		1.932
	群体颖花量Population spikelet number (X₃)			-0.791	-0.558	0.990**	1.135
	结实率Seed-setting rate (X₄)				0.876	-0.698	0.119
	千粒重1000-grain weight (X₅)					-0.437	0.092