Effects of Nitrogen Application on Rice Photosynthetic Characteristics, Nitrogen Uptake and Grain Yield Formation Under Rainfall-adapted Water Management

doi:10.16819/j.1001-7216.2019.8140

Abstract

Abstract:

【Objective】The research aims to make rational use of rainfall during rice growth, improve paddy nitrogen fertilizer management practice in the Jianghan Plain.【Method】The field plot experiment with two irrigation regimes (conventional flooding irrigation, FI; rainfall-adapted irrigation, RAI) and three nitrogen fertilizer managements (farmers’ fertilization practice, FFP; 30% urea+70% controlled release compound fertilizer, 30%N+70%CRF; optimized and reduced nitrogen fertilizer application, OPT-N) were carried out to study the effects of water and fertilizer managements on rainfall utilization rate, rice yield, photosynthetic characteristics, dry matter accumulation and nitrogen uptake and utilization.【Result】1) Compared with FI, RAI reduced the irrigation quantity by 41.7%, economized water resources while improved the ability of paddy to saving and utilizing rainfall, net photosynthetic rate (P_n), stomatal conductance (G_s), intercellular CO₂ concentration (C_i) and transpiration rate (T_r), dry matter accumulation, nitrogen absorption and grain yield in varying degrees during rice growth. 2) Compared with FFP treatment under two water management modes, OPT-N significantly decreased P_n, G_s, C_i, T_r, dry matter accumulation and nitrogen uptake of rice at tillering stage, but increased the above-mentioned indexes from booting to filling stages, but had little effect on final yield formation. 3) RAI combined with 30% N + 70% CRF treatment helped increase P_n, G_s, C_i and T_r in the early growth stage, and promoted the accumulation of dry matter significantly in the middle and late growth stages. The nitrogen uptake was significantly higher than in OPT-N and FFP during the tillering stage, and was significantly higher than FFP at the full heading stage and mature stage. Effective panicle number, panicle length, 1000-grain quality and seed setting rate were the highest among treatments, and the actual yield was 10.4% higher than that in conventional water and fertilizer management.【Conclusion】Under the rainfall-adapted irrigation, OPT-N had no significant effect on rice growth and yield, 30% N+70% CRF was helpful to increase photosynthesis, nitrogen uptake and yield of rice.

Key words: rainfall-adapted water management, nitrogen application, yield, photosynthetic characteristics, nitrogen uptake

摘要：

【目的】为合理利用水稻生长期间的降雨,改善江汉平原地区稻田氮肥管理。【方法】采用田间小区试验,研究了常规淹灌(FI)和适雨灌溉(RAI)条件下,农民习惯施肥(FFP)、30%尿素+70%控释掺混肥(30%N+70%CRF)和优化减氮施肥(OPT-N)对降雨利用率、水稻产量、光合特性、干物质积累及氮吸收利用的影响。【结果】1)RAI能在节省水资源同时提升稻田对雨水的储蓄和利用能力,与FI相比可减少田间灌溉水量41.7%,各生育阶段水稻叶片净光合速率(P_n)、气孔导度(G_s)、胞间CO₂浓度(C_i)和蒸腾速率(T_r)、干物质积累、氮素吸收以及产量均有不同程度的增加;2)两种水管理方式下,与FFP处理相比,OPT-N处理水稻在分蘖期的P_n、G_s、C_i、T_r、干物质积累和氮素吸收显著降低,但在孕穗期-灌浆期有所增加,对最终产量形成影响不大;RAI结合30%N+70%CRF处理有利于水稻生育前期P_n、G_s、C_i、T_r的增加,提升生育中后期干物质积累量,氮素吸收量在分蘖期显著高于OPT-N和FFP,在齐穗期和成熟期显著高于FFP,有效穗数、穗长、千粒质量和结实率在各处理间表现最高,实际产量相较常规水肥管理可增产10.4%。【结论】适雨灌溉条件下,OPT-N不会显著影响水稻的生长及产量,30%N+70%CRF有助于水稻光合作用、氮素吸收及产量的增加。

关键词: 适雨灌溉, 氮肥运筹, 产量, 光合特性, 氮素吸收

CLC Number:

Jun YAN, Qixia WU, Jianqiang ZHU, Luping ZHANG. Effects of Nitrogen Application on Rice Photosynthetic Characteristics, Nitrogen Uptake and Grain Yield Formation Under Rainfall-adapted Water Management[J]. Chinese Journal OF Rice Science, 2019, 33(4): 347-356.

晏军, 吴启侠, 朱建强, 张露萍. 适雨灌溉下氮肥运筹对水稻光合特性、氮素吸收及产量形成的影响[J]. 中国水稻科学, 2019, 33(4): 347-356.

Figures/Tables 7

References 31

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施肥处理 Fertilization treatment	施肥量 Fertilizer rate（N-P₂O₅-K₂O）	基肥 Base-manure amounts					分蘖初期 TS	幼穗分化期 PDS
施肥处理 Fertilization treatment	施肥量 Fertilizer rate（N-P₂O₅-K₂O）	控释掺混肥 CRF	普通复合肥 CF	尿素 Urea	过磷酸钙 S	氯化钾 MP	尿素 Urea	尿素 Urea
农民习惯施肥FFP	180-75-105	0.0	700.0	0.0	158.3	0.0	117.4	0.0
30%N+70%CRF	180-75-105	450.0	0.0	117.4	437.5	107.5	0.0	0.0
优化减氮施肥OPT-N	150-75-105	0.0	416.7	0.0	347.2	70.8	114.1	48.9

施肥处理 Fertilization treatment	施肥量 Fertilizer rate（N-P₂O₅-K₂O）	基肥 Base-manure amounts					分蘖初期 TS	幼穗分化期 PDS
施肥处理 Fertilization treatment	施肥量 Fertilizer rate（N-P₂O₅-K₂O）	控释掺混肥 CRF	普通复合肥 CF	尿素 Urea	过磷酸钙 S	氯化钾 MP	尿素 Urea	尿素 Urea
农民习惯施肥FFP	180-75-105	0.0	700.0	0.0	158.3	0.0	117.4	0.0
30%N+70%CRF	180-75-105	450.0	0.0	117.4	437.5	107.5	0.0	0.0
优化减氮施肥OPT-N	150-75-105	0.0	416.7	0.0	347.2	70.8	114.1	48.9

光合特征指标 Indicators of photosynthetic characteristics	处理 Treatment		生育期 Growth stage
光合特征指标 Indicators of photosynthetic characteristics	处理 Treatment		分蘖期 Tillering	拔节期 Jointing	孕穗期 Booting	齐穗期 Full-heading	灌浆期 Filling	乳熟期 Maturity
P_n/(μmol·m^-2s^-1)	FI	FFP	23.6±3.0 b	24.9±1.4 ab	21.2±5.4 b	26.0±0.8 a	15.9±3.4 a	7.3±1.4 b
		30%N+70%CRF	25.2±4.0 a	25.5±1.7 a	21.7±3.6 b	25.5±1.3 a	16.4±2.0 a	9.9±2.5 a
		OPT-N	21.7±3.2 b	23.6±1.5 b	26.8±5.1 a	26.6±2.3 a	16.7±2.0 a	11.0±3.2 a
	RAI	FFP	24.5±3.6 b	26.0±2.3 a	21.8±3.1 b	26.5±2.4 a	16.0±3.3 a	8.1±2.8 b
		30%N+70%CRF	27.7±1.8 a	25.4±2.1 a	24.6±3.0 ab	26.4±1.9 a	17.4±2.2 a	7.4±2.3 b
		OPT-N	22.0±2.3 b	24.8±1.3 a	25.9±2.9 a	26.2±2.9 a	16.7±2.2 a	11.2±2.9 a
G_s/(mol·m^-2s^-1)	FI	FFP	0.5±0.1 b	0.4±0.1 a	0.4±0.1 ab	0.5±0.1 ab	0.8±0.2 a	0.2±0.03 a
		30%N+70%CRF	0.6±0.1 a	0.4±0.1 a	0.3±0.1 b	0.5±0.1 b	0.5±0.1 b	0.2±0.04 a
		OPT-N	0.6±0.1 a	0.5±0.1 a	0.5±0.1 a	0.6±0.1 a	0.7±0.1 a	0.3±0.03 a
	RAI	FFP	0.4±0.2 b	0.4±0.2 b	0.4±0.1 b	0.6±0.1 ab	0.7±0.2 a	0.2±0.05 b
		30%N+70%CRF	0.6±0.1 a	0.4±0.1 b	0.4±0.1 ab	0.5±0.1 b	0.6±0.1 a	0.3±0.1 ab
		OPT-N	0.7±0.1 a	0.6±0.1 a	0.5±0.1 a	0.6±0.1 a	0.7±0.1 a	0.3±0.04 a
C_i/(μmol·mol^-1)	FI	FFP	285.2±33.4 b	241.0±38.5 a	289.0±18.8 a	294.0±5.7 a	323.9±15.4 a	355.3±8.7 a
		30%N+70%CRF	325.3±10.3 a	249.7±26.6 a	271.2±27.5 a	287.1±12.4 a	318.3±5.4 a	323.2±16.1 b
		OPT-N	301.8±13.7 b	261.9±15.0 a	273.1±18.6 a	293.4±7.7 a	318.5±8.2 a	346.8±23.8 ab
	RAI	FFP	305.5±16.4 b	253.2±21.9 b	300.2±8.8 a	292.9±7.5 a	319.9±11.5 a	354.0±18.1 b
		30%N+70%CRF	326.2±14.9 a	288.3±10.2 a	285.8±10.6 b	294.9±11.0 a	327.9±6.1 a	320.6±17.9 a
		OPT-N	330.1±8.0 a	254.4±22.6 b	280.6±7.2 b	295.4±9.2 a	327.0±9.1 a	335.1±19.6 a
T_r/(mmol·m^-2s^-1)	FI	FFP	4.4±0.9 b	3.0±0.8 a	4.2±0.7 b	5.9±0.5 b	4.3±0.4 b	5.5±0.4 a
		30%N+70%CRF	6.1±0.6 a	3.4±0.6 a	4.3±0.8 b	6.0±0.6 ab	4.7±0.3 ab	5.9±0.8 ab
		OPT-N	6.4±0.6 a	3.5±0.6 a	5.6±0.9 a	6.4±0.3 a	5.2±0.4 a	6.3±0.5 b
	RAI	FFP	4.5±1.2 b	3.0±1.0 b	4.6±0.4 b	6.0±0.7 b	4.9±0.5 a	5.0±1.0 b
		30%N+70%CRF	6.9±0.6 a	4.9±0.9 a	5.4±0.6 a	6.1±0.4 ab	4.9±0.4 a	5.8±0.7 a
		OPT-N	7.1±0.5 a	3.4±0.7 b	5.8±0.6 a	6.6±0.6 a	5.0±0.5 a	6.4±0.5 a

光合特征指标 Indicators of photosynthetic characteristics	处理 Treatment		生育期 Growth stage
光合特征指标 Indicators of photosynthetic characteristics	处理 Treatment		分蘖期 Tillering	拔节期 Jointing	孕穗期 Booting	齐穗期 Full-heading	灌浆期 Filling	乳熟期 Maturity
P_n/(μmol·m^-2s^-1)	FI	FFP	23.6±3.0 b	24.9±1.4 ab	21.2±5.4 b	26.0±0.8 a	15.9±3.4 a	7.3±1.4 b
		30%N+70%CRF	25.2±4.0 a	25.5±1.7 a	21.7±3.6 b	25.5±1.3 a	16.4±2.0 a	9.9±2.5 a
		OPT-N	21.7±3.2 b	23.6±1.5 b	26.8±5.1 a	26.6±2.3 a	16.7±2.0 a	11.0±3.2 a
	RAI	FFP	24.5±3.6 b	26.0±2.3 a	21.8±3.1 b	26.5±2.4 a	16.0±3.3 a	8.1±2.8 b
		30%N+70%CRF	27.7±1.8 a	25.4±2.1 a	24.6±3.0 ab	26.4±1.9 a	17.4±2.2 a	7.4±2.3 b
		OPT-N	22.0±2.3 b	24.8±1.3 a	25.9±2.9 a	26.2±2.9 a	16.7±2.2 a	11.2±2.9 a
G_s/(mol·m^-2s^-1)	FI	FFP	0.5±0.1 b	0.4±0.1 a	0.4±0.1 ab	0.5±0.1 ab	0.8±0.2 a	0.2±0.03 a
		30%N+70%CRF	0.6±0.1 a	0.4±0.1 a	0.3±0.1 b	0.5±0.1 b	0.5±0.1 b	0.2±0.04 a
		OPT-N	0.6±0.1 a	0.5±0.1 a	0.5±0.1 a	0.6±0.1 a	0.7±0.1 a	0.3±0.03 a
	RAI	FFP	0.4±0.2 b	0.4±0.2 b	0.4±0.1 b	0.6±0.1 ab	0.7±0.2 a	0.2±0.05 b
		30%N+70%CRF	0.6±0.1 a	0.4±0.1 b	0.4±0.1 ab	0.5±0.1 b	0.6±0.1 a	0.3±0.1 ab
		OPT-N	0.7±0.1 a	0.6±0.1 a	0.5±0.1 a	0.6±0.1 a	0.7±0.1 a	0.3±0.04 a
C_i/(μmol·mol^-1)	FI	FFP	285.2±33.4 b	241.0±38.5 a	289.0±18.8 a	294.0±5.7 a	323.9±15.4 a	355.3±8.7 a
		30%N+70%CRF	325.3±10.3 a	249.7±26.6 a	271.2±27.5 a	287.1±12.4 a	318.3±5.4 a	323.2±16.1 b
		OPT-N	301.8±13.7 b	261.9±15.0 a	273.1±18.6 a	293.4±7.7 a	318.5±8.2 a	346.8±23.8 ab
	RAI	FFP	305.5±16.4 b	253.2±21.9 b	300.2±8.8 a	292.9±7.5 a	319.9±11.5 a	354.0±18.1 b
		30%N+70%CRF	326.2±14.9 a	288.3±10.2 a	285.8±10.6 b	294.9±11.0 a	327.9±6.1 a	320.6±17.9 a
		OPT-N	330.1±8.0 a	254.4±22.6 b	280.6±7.2 b	295.4±9.2 a	327.0±9.1 a	335.1±19.6 a
T_r/(mmol·m^-2s^-1)	FI	FFP	4.4±0.9 b	3.0±0.8 a	4.2±0.7 b	5.9±0.5 b	4.3±0.4 b	5.5±0.4 a
		30%N+70%CRF	6.1±0.6 a	3.4±0.6 a	4.3±0.8 b	6.0±0.6 ab	4.7±0.3 ab	5.9±0.8 ab
		OPT-N	6.4±0.6 a	3.5±0.6 a	5.6±0.9 a	6.4±0.3 a	5.2±0.4 a	6.3±0.5 b
	RAI	FFP	4.5±1.2 b	3.0±1.0 b	4.6±0.4 b	6.0±0.7 b	4.9±0.5 a	5.0±1.0 b
		30%N+70%CRF	6.9±0.6 a	4.9±0.9 a	5.4±0.6 a	6.1±0.4 ab	4.9±0.4 a	5.8±0.7 a
		OPT-N	7.1±0.5 a	3.4±0.7 b	5.8±0.6 a	6.6±0.6 a	5.0±0.5 a	6.4±0.5 a

处理 Treatment		干物质积累量 Dry matter accumulation/(t·hm^-2)			各生育阶段干物质量所占比例 Proportion of dry matter accumulation in each growth stage/%
处理 Treatment		分蘖期 Tillering	齐穗期 Full-heading	成熟期 Maturity	移栽-分蘖期 Transplanting-Tillering	分蘖期-齐穗期 Tillering-Heading	齐穗期-成熟期 Heading-Maturity
FI	FFP	1.9±0.1 a	6.1±0.4 b	13.4±2.2 a	14.3 a	31.2 b	54.5 a
	30%N+70%CRF	2.3±0.3 a	8.8±0.9 a	15.0±1.9 a	15.4 a	42.8 a	41.8 b
	OPT-N	1.4±0.3 b	6.6±0.3 b	14.8±2.3 a	9.7 b	34.7 b	55.6 a
RAI	FFP	2.1±0.2 b	9.0±1.0 a	13.1±1.2 b	15.9 ab	52.6 a	31.5 b
	30%N+70%CRF	2.9±0.3 a	10.5±2.4 a	16.7±0.8 a	17.1 a	45.9 a	37.0 a
	OPT-N	1.7±0.2 c	9.4±1.5 a	15.2±1.3 ab	11.4 b	50.7 a	37.9 a