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作物学报 ›› 2021, Vol. 47 ›› Issue (12): 2481-2489.doi: 10.3724/SP.J.1006.2021.01090

• 耕作栽培·生理生化 • 上一篇    下一篇

小麦玉米同步增密有利于优化种间关系而提高间作产量

张金丹(), 范虹, 杜进勇, 殷文, 樊志龙, 胡发龙, 柴强*()   

  1. 甘肃农业大学农学院 / 甘肃省干旱生境作物学重点实验室, 甘肃兰州 730070
  • 收稿日期:2020-11-30 接受日期:2021-04-14 出版日期:2021-12-12 网络出版日期:2021-06-15
  • 通讯作者: 柴强
  • 作者简介:E-mail: zhangjd9522@163.com
  • 基金资助:
    国家自然科学基金项目(31771738);甘肃省基础研究创新群体项目(20JR5RA037);甘肃省自然科学基金项目(20JR5RA008);中央引导地方科技发展专项(ZCYD-2020-1-4)

Synchronously higher planting density can increase yield via optimizing interspecific interaction of intercropped wheat and maize

ZHANG Jin-Dan(), FAN Hong, DU Jin-Yong, YIN Wen, FAN Zhi-Long, HU Fa-Long, CHAI Qiang*()   

  1. Gansu Provincial Key Laboratory of Arid Land Crop Science / College of Agronomy, Gansu Agricultural University, Lanzhou 730070, Gansu, China
  • Received:2020-11-30 Accepted:2021-04-14 Published:2021-12-12 Published online:2021-06-15
  • Contact: CHAI Qiang
  • Supported by:
    National Natural Science Foundation of China(31771738);Innovation Group of Basic Research in Gansu Province(20JR5RA037);Natural Science Foundation of Gansu Province(20JR5RA008);Central Government will Guide Local Science and Technology Development Projects(ZCYD-2020-1-4)

摘要:

增密是间作高产的主要措施, 研究间作组分密度变化对其种间关系、产量的影响, 对于夯实间作理论与技术意义重大。2018—2019年, 在河西绿洲灌区开展田间试验, 设单作玉米、单作小麦、小麦/玉米3种种植模式, 4.5万株 hm-2(传统)、6.0万株 hm-2(中)、7.5万株 hm-2(高) 3种玉米密度, 284万粒 hm-2(传统)、341万粒 hm-2(高)两种小麦密度, 研究了小麦玉米同步增密对间作种间关系及产量的影响。结果表明, 间作小麦、玉米密度同步增大强化了共生期小麦相对于玉米的竞争力(Awm), 小麦高密度间作与传统密度间作相比, Awm提高了10.9%~20.1%; 玉米高、中密度间作与传统玉米密度间作相比, 其Awm分别提高了25.3%~32.0%、15.8%~17.3%; 小麦、玉米高密度间作与传统密度间作相比, Awm提高了35.5%~56.5%。间作小麦、玉米密度同步提高可增大麦后间作玉米的恢复效应(Rm), 小麦高密度间作较传统密度间作的Rm提高了14.6%~17.1%; 玉米高、中密度间作与传统密度间作相比, Rm分别提高了27.4%~48.5%、10.3%~30.5%; 小麦高密/玉米高密度较小麦/玉米传统密度处理Rm提高了43.7%~65.5%。增密有利于提高间作优势, 小麦高密/玉米高密度较小麦/玉米传统密度处理土地当量比高8.3%~10.8%。两作物同步增密可进一步提高间作增产优势, 小麦高密度间作较传统密度间作增产3.6%~5.1%, 玉米高、中密度间作较传统密度间作增产14.1%~19.3%、7.3%~15.2%, 小麦高密/玉米高密度较小麦/玉米传统密度处理增产19.0%~24.0%。间作小麦对玉米的竞争力及麦后玉米的恢复效应与间作籽粒产量均呈正相关。小麦玉米同步增密可优化间作种间关系、提高产量, 小麦播种量341万粒 hm-2和玉米7.5万株 hm-2是绿洲灌区小麦间作玉米高产的适宜密度。

关键词: 小麦间作玉米, 种植密度, 种间竞争力, 恢复效应, 产量

Abstract:

Increasing planting density is the main measure for high yield in intercropping. It is of great significance for the theory and technology of enhancing intercropping system to investigate the effects of intercrop’s density changes on the interspecific interaction and yield. In 2018 and 2019, a field experiment was carried out in Hexi oasis irrigation area, with three cropping patterns of monocropping maize, monocropping wheat, wheat-maize intercropping, and three maize densities of 45,000 plants hm-2 (traditional), 60,000 plants hm-2 (medium), 75,000 plants hm-2 (high), and two wheat densities of 2.84 million grains hm-2 (traditional) and 3.41 million grains hm-2 (high). The effect of synchronously higher planting densities of wheat and maize on inter-specific relationship and yield of intercropping system was studied. The results showed that the densities of intercropped wheat and maize were increased simultaneously, which strengthened the competitiveness of wheat relative to maize (Awm) during the co-growth period. For the intercropped wheat, compared to traditional planting density, high density increased the Awm by 10.9%-20.1%. For the intercropping maize, compared to traditional planting density, high density and medium density improved the Awm by 25.3%-32.0% and 15.8%-17.3%, respectively. In addition, compared to intercropped wheat and maize with traditional density, synchronously higher planting density for intercropped wheat and maize increased the Awm by 35.5%-56.5%. The simultaneous increase of the density of intercropped wheat and maize could increase the recovery growth effect of intercropped maize (Rm) after the intercropped wheat harvested. For the intercropped wheat, compared to traditional planting density, high density increased the Rm by 14.6%-17.1%. For the intercropping maize, compared to traditional planting density, high density and medium density improved Rm by 27.4%-48.5% and 10.3%-30.5%, respectively. In addition, compared to intercropped wheat and maize with traditional density, synchronously higher planting density for intercropped wheat and maize increased Rm by 43.7%-65.5%. Increasing planting density was conducive to improve the advantage of intercropping. The land equivalent ratio of high-density for both intercropped wheat and maize was 8.3%-10.8% higher than that of intercropped wheat and maize with traditional density. The simultaneous increase in the density of intercropped wheat and maize could further improve the advantage of intercropping. For the intercropped wheat, compared to traditional planting density, high density increased the grain yield of intercropping system by 3.6%-5.1%. For the intercropping maize, compared to traditional planting density, high density and medium density improved grain yield of intercropping system by 14.1%-19.3% and 7.3%-15.2%, respectively. Synchronously higher planting density for intercropped wheat and maize had greater grain yield of intercropping system by 19.0%-24.0% than that of intercropped wheat and maize with traditional density. A positive relationship was observed between total grain yield of intercropping system and the competitiveness of wheat relative to maize and the recovery growth of intercropped maize after intercropped wheat harvest. In conclusion, synchronously higher planting density could increase grain yield via optimizing interspecific interaction of intercropped wheat and maize. Our results revealed that 4.5 million grains hm-2 of wheat and 75,000 plants hm-2 of maize were the suitable planting densities for high yield of wheat and maize in intercropping system in oasis irrigation area.

Key words: wheat/maize intercropping, planting density, interspecific competitiveness, recovery effect, yield

表1

试验处理及代码"

处理
Treatment
种植方式
Tillage method
种植密度Planting density (×104 plants hm-2)
玉米Maize 小麦Wheat
SM1 单作玉米
Sole maize
7.8
SM2 10.35
SM3 12.9
SW1 单作小麦
Sole wheat
675
SW2 810
IW1M1 玉米间作小麦
Maize/wheat intercropping
4.5 284
IW1M2 6.0 284
IW1M3 7.5 284
IW2M1 4.5 341
IW2M2 6.0 341
IW2M3 7.5 341

图1

间作作物田间结构示意图 处理同表1。"

表2

不同密度处理对小麦/玉米间作系统竞争力的主效应分析"

处理
Treatment
竞争力Competition
5/10 # 5/30 6/19 7/9 7/29
小麦密度Density of wheat 0.048* 0.001** 0.000** 0.024* 0.000**
玉米密度Density of maize 0.626 0.000** 0.000** 0.000** 0.428
小麦密度×玉米密度Density of wheat × Density of maize 0.251 0.102 0.044* 0.001** 0.409

图2

2018年和2019年不同密度处理下间作系统小麦相对于玉米的竞争力表现 处理同表1。"

图3

2018年和2019年不同密度处理下玉米生长率动态 处理同表1。"

表3

不同玉米和小麦密度处理下小麦收获后间作玉米的恢复效应"

年际
Year
处理
Treatment
恢复效应Recovery effect
7/29-8/17 8/17-9/6 9/6-9/25
2018 IW1M1 1.49±0.05 b 1.35±0.03 c 1.18±0.14 d
IW1M2 1.36±0.04 c 1.54±0.12 b 1.23±0.04 d
IW1M3 1.26±0.05 d 1.62±0.14 b 2.13±0.09 ab
IW2M1 1.62±0.04 a 1.37±0.03 c 1.43±0.08 c
IW2M2 1.49±0.03 b 1.64±0.09 b 2.07±0.05 b
IW2M3 1.48±0.06 b 2.03±0.05 a 2.28±0.19 a
2019 IW1M1 0.96±0.05 c 1.35±0.03 c 1.04±0.02 d
IW1M2 1.18±0.04 b 1.43±0.02 b 1.60±0.08 c
IW1M3 1.18±0.01 b 1.56±0.02 a 1.99±0.07 b
IW2M1 1.13±0.04 b 1.40±0.06 c 1.06±0.15 d
IW2M2 1.34±0.13 a 1.44±0.04 b 2.10±0.06 b
IW2M3 1.19±0.01 b 1.64±0.01 a 2.72±0.06 a
主效应分析Main effects analysis
小麦密度Density of wheat 0.041* 0.016* 0.002**
玉米密度Density of maize 0.709 0.000** 0.000**
小麦密度×玉米密度
Density of wheat × Density of maize
0.962 0.039* 0.017*

图4

2018-2019年小麦/玉米间作不同密度处理的土地当量比 不同小写字母表示同一年份各处理间差异达到显著水平(P < 0.05)。"

图5

2018年和2019年小麦/玉米间作不同密度处理的籽粒产量 不同小写字母表示同一年份各处理间差异达到显著水平(P < 0.05)。"

图6

小麦/玉米间作种间关系与籽粒产量间的相关性"

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