不同保绿型玉米杂交种氮效率评价

doi:10.3864/j.issn.0578-1752.2026.06.006

摘要/Abstract

摘要：

【目的】保绿性是与玉米高产、优质和抗逆等方面密切相关的重要农艺性状。探讨不同保绿型玉米杂交种氮素吸收和转运的差异，为玉米氮高效生理机制提供理论依据。【方法】供试材料为陕单650和郑单958。于2023年设置6个氮处理，分别为N1（不施氮）、N2（60 kg·hm^-2）、N3（120 kg·hm^-2）、N4（180 kg·hm^-2）、N5（240 kg·hm^-2）、N6（300 kg·hm^-2）；于2024年设置氮肥施用与种植密度（氮密）互作试验，包含低氮（LN，不施氮）、中氮（MN，180 kg·hm^-2）、高氮（HN，240 kg·hm^-2）3种施氮量和低密（LD，60 000株/hm²）、高密（HD，75 000株/hm²）2种种植密度。测定玉米吐丝期后对各个处理的穗位叶叶绿素相对含量（SPAD）、整株绿叶数、干物质及营养体和籽粒氮素积累量等指标，并分析氮素吸收转运率与氮效率相关指标。【结果】两玉米杂交种产量随施氮量的增加呈先增加后趋于平稳的趋势，不同氮处理及氮密互作下，陕单650产量均高于郑单958；吐丝后，陕单650表现出比郑单958更高的叶绿素降解速率和绿叶数减少幅度，尤其在低氮条件下，其穗位叶SPAD值降幅（65.1%）显著高于郑单958（49.9%），且叶绿素流失更早、更快；在不同氮处理和氮密互作下，玉米杂交种陕单650表现出更强的氮素转运效率，尤其在低氮条件下，其成熟期叶片氮转运量显著高于郑单958，且转运优势随密度增加进一步放大，验证了陕单650作为功能保绿型品种的氮素高效再动员特性；整体上陕单650营养体氮素转运率、氮肥利用率、氮肥农学效率、氮素收获指数等均显著高于郑单958，且在高密度种植模式下，合理减氮能够进一步提升其氮效率表现。【结论】功能保绿型玉米品种陕单650具有保持绿色和光合作用的一致性，有直到作物生理成熟前某一时间段快速失绿、光合下降并实现氮素再分配的特点。较高的营养体氮素转运能力使其具备在合理的减氮增密下表现更高氮效率的潜力。

关键词: 玉米, 氮效率, 保绿性, 产量, 氮素

Abstract:

【Objective】Stay-green trait is an important agronomic characteristic closely related to high yield, good quality, and stress resistance of maize. This study explored the differences in nitrogen uptake and translocation of different stay-green maize hybrids, aiming to provide a theoretical basis for the physiological mechanism of high nitrogen efficiency in maize. 【Method】The tested materials were the stay-green hybrid Shandan 650 and the non-stay-green hybrid Zhengdan 958. In 2023, 6 N treatments were applied: N1 (0 kg·hm^-2), N2 (60 kg·hm^-2), N3 (120 kg·hm^-2), N4 (180 kg·hm^-2), N5 (240 kg·hm^-2), and N6 (300 kg·hm^-2). In 2024, a nitrogen×density interaction experiment was conducted with three N levels—low N (LN, 0 kg·hm^-2), medium N (MN, 180 kg·hm^-2), and high N (HN, 240 kg·hm^-2)—and two planting densities—low density (LD, 60 000 plants·hm^-2) and high density (HD, 75 000 plants·hm^-2). After the silking stage of maize, indicators were determined for each treatment, such as SPAD value of ear leaves, total number of green leaves per plant, dry matter, and nitrogen accumulation in vegetative organs and grains. Meanwhile, nitrogen absorption and translocation rates as well as nitrogen use efficiency-related indicators were analyzed. 【Result】 Grain yield of both hybrids initially increased and then stabilized with rising N rates, with Shandan 650 consistently outperforming Zhengdan 958 across all N and density treatments. Post-silking, Shandan 650 exhibited faster chlorophyll degradation (SPAD decline: 65.1% vs. 49.9%) and greater green leaf loss than Zhengdan 958, particularly under low N. Shandan 650 demonstrated superior N remobilization efficiency, especially under low N and high density, with significantly higher N translocation from leaves to grains. Overall, Shandan 650 achieved significantly higher N remobilization efficiency, nitrogen use efficiency, nitrogen agronomic efficiency, and nitrogen harvest index than Zhengdan 958. Furthermore, under high-density planting conditions, reasonable nitrogen reduction further enhanced its nitrogen efficiency performance. 【Conclusion】 The functional stay-green maize variety Shandan 650 maintains consistent greenness and photosynthetic capacity until a certain period before physiological maturity, at which point a rapid decline occurs along with nitrogen remobilization. Its strong nitrogen translocation capacity in vegetative organs enhances nitrogen translocation rate and nitrogen use efficiency, and higher nitrogen efficiency could be achieved under reasonable nitrogen reduction and density increase.

Key words: maize, nitrogen use efficiency, stay-green, yield, nitrogen

何继航, 张擎, 吕相月, 薛吉全, 徐淑兔, 刘建超. 不同保绿型玉米杂交种氮效率评价[J]. 中国农业科学, 2026, 59(6): 1217-1230.

HE JiHang, ZHANG Qing, LÜ XiangYue, XUE JiQuan, XU ShuTu, LIU JianChao. Evaluation of Nitrogen Efficiency of Different Stay-Green Maize Hybrids[J]. Scientia Agricultura Sinica, 2026, 59(6): 1217-1230.

图/表 10

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表2

不同氮处理和氮密互作下玉米杂交种氮效率评价"

年份 Year	处理 Treatment	品种 Varieties	氮素利用效率 Nitrogen utilization efficiency	氮素吸收效率 Nitrogen uptake efficiency	氮肥利用率 Nitrogen use efficiency	氮肥农学效率 Nitrogen agronomic efficiency	氮素转运对籽粒贡献率 Nitrogen contribution proportion	氮素收获指数 Nitrogen harvest index
2023	N1	陕单650 Shandan650	61.63±1.54a	-	-	-	0.76±0.02a	0.75±0.03a
	N1	郑单958 Zhengdan985	57.84±1.11b	-	-	-	0.67±0.02b	0.62±0.03b
	N2	陕单650 Shandan650	58.92±0.79a	2.35±0.03a	0.71±0.01a	43.78±1.82a	0.74±0.03a	0.77±0.07a
	N2	郑单958 Zhengdan985	56.64±0.43b	2.23±0.18a	0.63±0.04b	39.25±1.05b	0.66±0.02b	0.60±0.04b
	N3	陕单650 Shandan650	56.82±0.98a	1.47±0.16a	0.65±0.01a	37.17±0.80a	0.71±0.02a	0.72±0.05a
	N3	郑单958 Zhengdan985	54.23±0.57b	1.42±0.03a	0.64±0.01a	31.33±1.30b	0.63±0.02b	0.58±0.01b
	N4	陕单650 Shandan650	53.74±0.82a	1.12±0.05a	0.59±0.01a	26.53±1.41a	0.68±0.03a	0.70±0.03a
	N4	郑单958 Zhengdan985	53.18±1.62a	1.05±0.05a	0.56±0.01b	24.48±1.35a	0.62±0.02b	0.59±0.03b
	N5	陕单650 Shandan650	53.05±1.65a	0.85±0.02a	0.47±0.01a	21.40±1.00a	0.64±0.03a	0.70±0.03a
	N5	郑单958 Zhengdan985	50.13±0.44b	0.81±0.02a	0.45±0.01b	18.91±1.17b	0.64±0.03a	0.55±0.05b
	N6	陕单650 Shandan650	52.01±2.26a	0.69±0.04a	0.40±0.01a	15.65±0.96a	0.63±0.04a	0.63±0.01a
	N6	郑单958 Zhengdan985	48.96±0.95a	0.67±0.03a	0.36±0.03b	16.17±0.66b	0.61±0.04a	0.54±0.05b
2024	LNHD	陕单650 Shandan650	65.71±2.33a	-	-	-	0.70±0.02a	0.76±0.01a
	LNHD	郑单958 Zhengdan985	55.88±3.14b	-	-	-	0.64±0.02b	0.67±0.01b
	LNLD	陕单650 Shandan650	64.04±2.35a	-	-	-	0.65±0.01a	0.74±0.01a
	LNLD	郑单958 Zhengdan985	57.61±1.23b	-	-	-	0.62±0.01b	0.65±0.03b
	MNHD	陕单650 Shandan650	59.46±0.41a	1.05±0.05a	0.59±0.01a	31.46±2.10a	0.64±0.02a	0.67±0.02a
	MNHD	郑单958 Zhengdan985	54.92±1.15b	0.97±0.01a	0.56±0.01b	22.14±3.92b	0.60±0.01b	0.63±0.01b
	MNLD	陕单650 Shandan650	56.37±1.67a	1.12±0.03a	0.56±0.03a	28.37±0.93a	0.62±0.02a	0.65±0.03a
	MNLD	郑单958 Zhengdan985	51.80±2.08b	1.09±0.02a	0.50±0.02b	23.37±2.26b	0.59±0.02a	0.62±0.01a
	HNHD	陕单650 Shandan650	53.41±0.55a	0.64±0.01a	0.38±0.01a	17.67±1.20a	0.59±0.01a	0.61±0.01a
	HNHD	郑单958 Zhengdan985	51.26±0.85b	0.64±0.02a	0.35±0.01b	13.90±2.28a	0.55±0.01b	0.58±0.01b
	HNLD	陕单650 Shandan650	53.63±0.52a	0.67±0.02a	0.35±0.01a	16.17±0.53a	0.57±0.01a	0.59±0.01a
	HNLD	郑单958 Zhengdan985	50.22±0.83b	0.66±0.01a	0.32±0.01b	14.46±0.56b	0.54±0.01b	0.56±0.02a

表2

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年份 Year	全氮 Total nitrogen (g·kg^-1)	碱解氮 Alkali-hydrolyze nitrogen (mg·kg^-1)	有机质 Organic matter (mg·kg^-1)	速效磷 Available phosphorus (mg·kg^-1)	速效钾 Available potassium (mg·kg^-1)	pH
2023	0.54	66.12	12.64	12.14	131.11	8.5
2024	0.46	51.24	13.45	15.71	133.37	8.8