绿洲灌区密植对氮肥减量玉米产量的补偿潜力

doi:10.3864/j.issn.0578-1752.2024.09.007

摘要/Abstract

摘要：

【目的】针对绿洲灌区玉米生产氮肥用量过高的问题，探究通过密植补偿氮肥减量对玉米产量负效应的可行性。【方法】2019—2021年，以施氮水平为主区，设地方习惯施氮（N₂，360 kg·hm^-2）、减量25%施氮（N₁，270 kg·hm^-2）两个水平；以种植密度为副区，设传统（M₁，7.8万株/hm²）、中（M₂，10.4万株/hm²，增密33%）、高（M₃，12.9万株/hm²，增密66%）3个密度水平，进行裂区试验，重点研究氮肥减量条件下增密对玉米产量及其构成因素的影响。【结果】（1）氮肥减量导致玉米籽粒产量、生物产量分别降低4.0%、4.9%。减氮条件下，中密度可以产生籽粒产量补偿效应，N₁M₂较对照N₂M₁提高4.1%；高密度处理N₁M₃生物产量补偿效应最大，较对照提高14.2%。（2）通过回归分析模拟得到：减氮条件下，当种植密度提高至8.4万株/hm²可以与对照N₂M₁籽粒产量持平，并在10.6万株/hm²时获得最大产量13 537 kg·hm^-2，较对照提高4.9%。（3）氮肥减量引起穗数、穗粒数和千粒重分别降低5.0%、3.3%和3.4%；中、高密度分别较传统密度提高穗数27.9%、49.7%，降低穗粒数3.8%、8.4%，降低千粒重5.2%、8.9%。中密度较传统密度对收获指数无显著影响，而高密度使收获指数降低14.2%。N₁M₂较对照N₂M₁通过穗数增加补偿了减氮引起穗数、穗粒数及千粒重的下降，从而实现丰产。（4）氮肥减量降低拔节期至抽雄吐丝期的玉米生长率7.2%—8.4%；中、高密度较传统密度提高苗期至大喇叭口期玉米生长率27.3%、60.3%。（5）氮肥减量条件下，N₁M₂较对照提高叶、茎和鞘干物质转运量达9.6%、13.6%和3.7%，提高叶和茎对籽粒产量的贡献率5.3%和9.0%。【结论】通过合理密植可以补偿减氮引起的玉米产量下降，在施氮量270 kg·hm^-2的基础上增密至10.4万株/hm²，能够最大化产量补偿效应，是绿洲灌区玉米节氮稳产丰产的可行措施。

关键词: 玉米密植, 氮肥减量, 补偿潜力, 产量, 绿洲灌区

Abstract:

【Objective】To address the issue of excessive nitrogen fertilizer use for maize production in an oasis irrigation area, this study investigated the compensation effect for nitrogen fertilizer reduction through dense planting on maize yield.【Method】From 2019 to 2021, a two-factor split-plot experiment was carried out to explore the effect of different maize densities on yield and yield components under nitrogen reduction conditions. The main plot was two nitrogen application rate, including 25% reduction (N₁, 270 kg·hm^-2) and local habitual nitrogen application (N₂, 360 kg·hm^-2), and sub-plot was three planting densities of maize, including traditional (M₁, 78 000 plants/hm²), medium (M₂, 104 000 plants/hm², 33% increase), and high planting density (M₃, 129 000 plants/hm², 66% increase).【Result】(1) The grain yield and biomass of maize under N₁decreased by 4.0% and 4.9% than that under N₂respectively due to nitrogen reduction, which could be compensated by dense planting. The grain yield of N₁M₂ was increased by 4.1% compared with that of the control treatment (N₂M₁), while the biomass of treatment of high density and nitrogen reduction (N₁M₃) had the largest compensation effect, which was increased by 14.2% compared with that under the control. (2) According to the regression analysis, at the N₁ level, the density of 84 000 plants/hm² could get the equal grain yield of the control treatment, and reached the maximum grain yield of 13 537 kg·hm^-2 at 106 000 plants/hm², achieving a 4.9% increase in grain yield. (3) Compared with N₂, N₁ reduced maize ear number, kernel number per ear, and 1 000-kernel weight by 5.0%, 3.3%, and 3.4%, respectively, but had no significant effect on the harvest index. M₂ and M₃ increased the maize ear number by 27.9% and 49.7%, reduced kernel number per ear by 3.8% and 8.4%, respectively, and decreased 1 000-kernel weight by 5.2% and 8.9%, respectively. M₂ had no significant effect on the harvest index, while M₃ significantly reduced the harvest index by 14.2%. Therefore, compared with N₂M₁, N₁M₂ compensated for the decrease in ear number, kernel number per ear, and 1 000-kernel caused by nitrogen reduction through the increase of ear number. (4) N₁ decreased the maize growth rate from the jointing stage to the tasseling and silking stage by 7.2%-8.4%, while M₂ and M₃ significantly increased the maize growth rate by 27.3% and 60.3% compared with traditional density from the seedling stage to the trumpet stage. (5) Compared with N₂M₁, N₁M₂ increased maize leaf,stem, and sheath dry matter transportation amount (DTA) by 9.6%, 13.6%, and 3.7%, respectively, and the contribution rate of vegetative organs to grain (GCR) by 5.3% and 9.0%, respectively.【Conclusion】In the oasis irrigation area, the maize grain yield decrease caused by nitrogen reduction could be compensated by reasonably dense planting. Increasing the density to 104 000 plants/hm² based on 25% nitrogen reduction could maximize the yield compensation effect, which was a feasible measure to save nitrogen for a stable and high yield of maize.

Key words: maize dense planting, nitrogen fertilizer reduction, compensation potential, grain yield, oasis irrigation area

范虹, 殷文, 胡发龙, 樊志龙, 赵财, 于爱忠, 何蔚, 孙亚丽, 王凤, 柴强. 绿洲灌区密植对氮肥减量玉米产量的补偿潜力[J]. 中国农业科学, 2024, 57(9): 1709-1721.

FAN Hong, YIN Wen, HU FaLong, FAN ZhiLong, ZHAO Cai, YU AiZhong, HE Wei, SUN YaLi, WANG Feng, CHAI Qiang. Compensation Potential of Dense Planting on Nitrogen Reduction in Maize Yield in Oasis Irrigation Area[J]. Scientia Agricultura Sinica, 2024, 57(9): 1709-1721.

图/表 10

表1

表2

表3

图1

图2

表4

图3

图4

表5

不同处理玉米各器官干物质运转及对籽粒的贡献率"

年份 Year	施氮 Nitrogen	密度 Density	转运量 DTA (kg)			转运率 DTR (%)			贡献率 GCR (%)
年份 Year	施氮 Nitrogen	密度 Density	叶 Leaf	茎 Stem	鞘 Sheath	叶 Leaf	茎 Stem	鞘 Sheath	叶 Leaf	茎 Stem	鞘 Sheath
2019	N₁	M₁	1166±29c	1708±27c	621±33a	24.6±1ab	17.1±0.9ab	17.6±1.2a	9.3±0.5a	13.6±0.7a	5.0±0.3a
		M₂	1374±14a	2034±51a	604±21a	26.7±0.3a	17.8±0.4a	15.5±0.7ab	10.1±0.1a	14.9±0.4a	4.4±0.2a
		M₃	1289±16b	1830±29b	515±18b	22.9±0.3b	15.1±0.2b	12.9±0.9b	10.1±0.1a	14.3±0.8a	4.0±0.3a
	N₂	M₁	1287±42b	1862±53b	586±21a	25.7±2.1a	17.4±0.7a	15.7±2.6ab	9.5±0.8a	13.7±0.9a	4.3±0.8a
		M₂	1363±10a	1873±34b	587±19a	24.1±0.4ab	15.9±1.5ab	14.7±0.3ab	9.8±0.1a	13.4±1.5a	4.2±0.1a
		M₃	1369±13a	1962±12a	591±17a	22.9±0.2b	15.7±0.7ab	14.3±1b	10.3±0.1a	14.8±0.5a	4.5±0.3a
2020	N₁	M₁	1099±22b	1469±41bc	451±21b	25.0±0.6a	17.6±0.4a	14.1±0.3a	8.9±0.2a	11.9±0.3a	3.7±0.2a
		M₂	1270±27a	1580±43ab	471±16b	25.1±0.6a	16.2±0.5ab	13.1±0.3bc	9.1±0.2a	11.3±0.3abc	3.4±0.3a
		M₃	1239±31a	1383±50cd	442±20b	22.2±1.3c	12.4±0.9e	10.9±0.4d	9.1±0.5a	10.2±0.8bc	3.3±0.3a
	N₂	M₁	1139±26b	1296±53d	458±16b	24.2±1.2ab	14.3±0.6cd	14.0±0.4a	8.8±0.5a	10.1±0.4c	3.6±0.2a
		M₂	1232±17a	1603±75a	507±24a	23.6±0.3abc	15.4±0.8bc	13.3±0.6ab	8.6±0.4a	11.2±0.7abc	3.5±0.2a
		M₃	1285±38a	1617±51a	508±18a	22.9±0.5bc	13.7±0.5de	12.4±0.3c	9.1±0.3a	11.4±0.4ab	3.6±0.4a
2021	N₁	M₁	1188±61c	1528±78b	500±26ab	26.5±1.4ab	17.4±0.9a	15.8±0.8a	9.5±0.5b	12.2±0.6b	4.0±0.2a
		M₂	1371±70ab	1819±93a	549±28a	27.8±1.4ab	17.8±0.9a	15.7±0.3a	10.6±0.5ab	14.0±0.7a	4.2±0.3a
		M₃	1219±62bc	1537±78b	503±26ab	21.2±1.1d	13.2±0.7b	12.6±0.6b	10.0±0.5ab	12.7±0.6ab	4.1±0.3a
	N₂	M₁	1241±63abc	1661±85ab	522±27a	24.7±1.3bc	16.6±0.8a	15.0±0.8a	9.9±0.5ab	13.2±0.7ab	4.2±0.2a
		M₂	1292±66abc	1808±92a	448±23b	23.2±1.2cd	16.4±0.8a	12±0.6b	9.4±0.4b	13.1±0.7ab	3.2±0.2b
		M₃	1380±70a	1738±89a	520±26a	21.8±1.1d	13.8±0.7b	12.2±0.6b	10.8±0.6a	13.6±0.7ab	4.1±0.4a
方差分析Analysis of variance
年 Year (Y)			NS	NS	NS	NS	NS	NS	NS	NS	NS
氮肥 Nitrogen (N)			*	*	NS	NS	NS	NS	NS	NS	NS
密度 Density (D)			**	**	NS	NS	*	**	**	NS	*
年×氮肥 Y×N			NS	NS	*	*	NS	*	*	NS	NS
年×密度 Y×D			*	NS	NS	NS	NS	NS	**	NS	NS
密度×氮肥 D×N			*	NS	NS	*	NS	NS	NS	NS	NS
年×密度×氮肥 Y×D×N			NS	NS	NS	NS	NS	NS	NS	NS	NS

表5

图5

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年份 Year	项目 Item	四月 April	五月 May	六月 June	七月 July	八月 August	九月 September	全生育期 Entire growth period
2019	降雨量 Precipitation (mm)	7.5	26.4	61.3	30.0	25.2	19.9	170.3
2019	气温 Temperature (℃)	13.2	15.2	20.2	21.5	21.1	16.1	17.9
2020	降雨量 Precipitation (mm)	0	11.4	10.3	28.4	31.5	64.3	145.9
2020	气温 Temperature (℃)	10.7	16.4	21.4	22.6	20.9	15.8	18.0
2021	降雨量 Precipitation (mm)	26.8	12.9	31.0	6.0	16.3	69.5	162.5
2021	气温 Temperature (℃)	10.4	17.3	20.2	25.7	21.6	18.9	19.0

施氮水平 Nitrogen rate (kg·hm^-2)	玉米种植密度 Maize planting density (10⁴ plant/hm²)
施氮水平 Nitrogen rate (kg·hm^-2)	M₁(7.8)	M₂(10.4)	M₃(12.9)
N₁ (270)	N₁M₁	N₁M₂	N₁M₃
N₂ (360)	N₂M₁(对照 Control)	N₂M₂	N₂M₃

年份 Year	施氮 Nitrogen	密度 Density	籽粒产量 Grain yield (kg·hm^-2)	生物产量 Biomass (kg·hm^-2)	穗数 Ear number (10⁴·hm^-2)		穗粒数 Kernels per ear	千粒重 1000-grain weight (g)
2019	N₁	M₁	12530±131d	28480±341d	7.22±0.27c		535±17a	374±10abc
		M₂	13633±114ab	31055±453b	9.20±0.38b		519±11ab	357±18bc
		M₃	12794±325cd	32412±491a	10.64±0.22a		501±12b	350±12c
	N₂	M₁	13605±213ab	29736±640c	7.47±0.38c		542±17a	387±12a
		M₂	13974±300a	32228±645a	9.67±0.37b		536±15a	377±9ab
		M₃	13265±151bc	33037±390a	11.25±0.43a		510±13b	357±8bc
2020	N₁	M₁	12295±151d	25927±587f	8.05±0.33d		491±15b	338±10ab
		M₂	14032±142a	29182±512d	9.40±0.25c		477±17bc	311±11cd
		M₃	13559±83b	32514±307b	11.87±0.5a		462±14c	297±12d
	N₂	M₁	12890±299c	27314±417e	8.53±0.47d		530±18a	348±11a
		M₂	14307±286a	30941±666c	10.44±0.42b		507±21ab	328±18bc
		M₃	14198±290a	33320±448a	12.00±0.33a		485±16b	302±12d
2021	N₁	M₁	12496±189bc	25085±720e	7.17±0.3c		552±18ab	348±12a
		M₂	12954±208b	27790±769d	9.27±0.43b		529±20bc	326±13b
		M₃	12141±250c	31488±518b	10.99±0.35a		499±22c	325±14b
	N₂	M₁	12542±245bc	27347±798d	7.12±0.47c		576±19a	359±12a
		M₂	13788±194a	29705±784c	10.29±0.53a		534±13bc	342±9ab
		M₃	12741±367b	33763±638a	11.47±0.47a		499±26c	331±10b
方差分析Analysis of variance
年 Year (Y)			*	NS	NS	*			**
氮肥 Nitrogen (N)			**	**	**	*			*
密度 Density (D)			**	**	**	**			*
年×氮肥 Y×N			NS	NS	NS	NS			NS
年×密度 Y×D			NS	NS	NS	NS			NS
密度×氮肥 D×N			**	NS	NS	NS			NS
年×密度×氮肥 Y×D×N			**	NS	NS	NS			NS

产量构成因素 Yield component	与籽粒产量的相关系数 Correlation coefficient with yield	直接通径系数 Direct path coefficient	间接通径系数 Indirect path coefficient
产量构成因素 Yield component	与籽粒产量的相关系数 Correlation coefficient with yield	直接通径系数 Direct path coefficient	穗数 Ear number	穗粒数 Kernels per ear	千粒重 1000-grain weight
穗数 Ear number	0.687**	0.311	-	0.033	0.342
穗粒数 Kernels per ear	-0.635**	-0.040	-0.259	-	-0.336
千粒重1000-grain weight	-0.712**	-0.440	-0.242	-0.031	-