模拟大气CO2浓度升高与氮添加对宁夏枸杞生长及光合特性的影响

doi:10.12302/j.issn.1000-2006.202210041

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南京林业大学学报（自然科学版） ›› 2024, Vol. 48 ›› Issue (4): 209-218.doi: 10.12302/j.issn.1000-2006.202210041

模拟大气CO₂浓度升高与氮添加对宁夏枸杞生长及光合特性的影响

马冲¹(), 陆晖¹, 李运毛¹, 曹兵¹^,^*(), 朱金忠², 亢彦东²

1.宁夏大学农学院,宁夏银川 750021
2.宁夏中宁县杞鑫枸杞苗木专业合作社,宁夏中宁 755100

收稿日期:2022-10-31 修回日期:2023-06-07 出版日期:2024-07-30 发布日期:2024-08-05
通讯作者: *曹兵(bingcao2006@126.com),教授。
作者简介:
马冲(machong318@126.com),硕士。
基金资助:
宁夏中宁县枸杞产业专项基金项目(20211201);国家自然科学基金项目(32160393);国家自然科学基金项目(31660199)

Effects of elevated CO₂ concentration and nitrogen addition in simulated atmosphere on growth and photosynthetic characteristics of Lycium barbarum

MA Chong¹(), LU Hui¹, LI Yunmao¹, CAO Bing¹^,^*(), ZHU Jinzhong², KANG Yandong²

1. School of Agriculture, Ningxia University, Yinchuan 750021, China
2. Qixin Professional Cooperative of Goji Seedling in Zhongning, Zhongning 755100, China

Received:2022-10-31 Revised:2023-06-07 Online:2024-07-30 Published:2024-08-05

摘要/Abstract

摘要：

【目的】探究大气CO₂浓度升高与氮添加对宁夏枸杞生长发育特性、光合特性及产量的影响,为更好发掘宁夏枸杞的生产潜力及适应性栽培提供理论参考。【方法】以1年生‘宁杞1号’扦插苗为试验材料,采用开顶气室控制系统设置自然环境CO₂浓度[T1,(380±20)μmol/mol)]和升高CO₂浓度[T2,(760±20)μmol/mol],设置3个氮添加水平(以每kg土壤施加高氮水溶肥量计)N0(0 g/kg)、N1(0.8 g/kg)和N2(1.6 g/kg),共计6个处理。分别于处理45、60、75、90 d测定‘宁杞1号’株型、光合指标、日均净光合速率及单株产量。【结果】随着CO₂与氮素复合处理时间的延长,‘宁杞1号’苗地径、新梢长度和粗度、叶片气孔导度呈增加趋势,气孔限制值呈降低趋势,叶绿素含量呈先升后降再升模式。T2N1处理各时期新梢长度、粗度及叶片胞间CO₂浓度较高。T2处理60、75、90 d‘宁杞1号’的净光合速率均显著高于T1处理,其中T2N1处理下‘宁杞1号’净光合速率同比增长87.72%、68.33%、67.56%(P<0.01);CO₂浓度升高条件下,N1处理45、60、75、90 d时‘宁杞1号’的蒸腾速率均显著上升(P<0.05),但N2处理45、60 d时‘宁杞1号’的蒸腾速率均显著降低(P<0.05),分别为2.84、2.41 mmol/(m²·s)(P<0.05),N0处理75、90 d时‘宁杞1号’气孔导度显著升高(P<0.05),N1处理75、90 d时‘宁杞1号’的水分利用率显著增加(P<0.05),分别为10.68、9.34 g/kg,但气孔限制值处于较低水平。CO₂浓度升高条件下氮素添加降低了气孔限制值与新梢长度、粗度、叶绿素含量及枸杞单株产量的相关性,提高了蒸腾速率、净光合速率、水分利用效率与新梢长度、粗度等株型指标及枸杞单株产量的相关性;根据日均净光合速率模型,CO₂浓度升高条件下,‘宁杞1号’理论最佳施氮量为0.875 g/kg(土壤),此时‘宁杞1号’单株产量略高于T1N1处理。【结论】CO₂浓度升高条件下,N1处理增加了‘宁杞1号’的地径、新梢粗度,提高了‘宁杞1号’叶绿素含量、净光合速率、气孔导度和水分利用率,降低了其气孔限制值,且N1处理可以保持‘宁杞1号’较高的产量,降低CO₂浓度升高带来的负面影响,更适合CO₂浓度升高条件下枸杞的种植。

关键词: 宁夏枸杞‘宁杞1号’, 夏果期, 氮添加, CO₂浓度升高, 光合特性

Abstract:

【Objective】This study aims to investigate the effects of various nitrogen treatments on the growth, photosynthesis, and yield of Lycium barbarum under elevated atmospheric CO₂ concentrations. The objective is to optimize the production and adaptive cultivation of L. barbarum. 【Method】One-year-old cuttings of L. barbarum ‘Ningqi-1’ were used as experimental material. Two CO₂ concentrations were tested: ambient (T1, (380±20) μmol/mol) and elevated (T2, (760±20) μmol/mol), using an open-top chamber control system. Additionally, three nitrogen levels were applied per kilogram of soil: 0 g/kg (N0), 0.8 g/kg (N1) and 1.6 g/kg (N2). Measurements of plant morphology, photosynthetic indices, daily net photosynthetic rates, and yield were taken at 45, 60, 75 and 90 days.【Result】Over time, the combination of elevated CO₂ and nitrogen treatments enhanced the stem diameter, shoot length, thickness, and stomatal conductance of ‘Ningqi-1’, while inhibited the stomatal limit. The chlorophyll content initially increased, then decreased, and later increased again. The T2N1 treatment performs the best during each assessment period. The net photosynthetic rate of “Ningqi-1” treated with T2 for 60, 75 and 90 days was significantly higher than that of T1, with increases of 87.72%, 68.33% and 67.56%, respectively, reaching rates of 25.24, 28.33, and 28.25 μmol/(m²·s),respectively (P<0.01). With elevated CO₂ levels, the transpiration rate of “Ningqi-1” significantly increased during the N1 treatment across 45, 60, 75, 90 days but significantly decreased during the N2 treatment at 45 and 60 days, recording 2.84 and 2.41 mmol/(m²·s), respectively. Additionally, stomatal conductance of “Ningqi-1” significantly increased from 75 to 90 days (P<0.05). Water use efficiency significantly increased from 75 to 90 days post-N1 treatment, reaching 10.68 and 9.34 g/kg, while the stomatal limit remained low. Increasing CO₂ concentrations reduced the correlation among stomatal limitation and variables such as shoot length, thickness, chlorophyll content, and yield per plant. Conversely, it enhanced the correlation between transpiration rate, net photosynthetic rate, water use efficiency, and the aforementioned plant traits in “Ningqi-1.” Based on the CO₂ concentration model for daily net photosynthetic rate, the optimal theoretical nitrogen application rate for “Ningqi-1” was estimated at 0.875 g/kg (soil). The yield per plant under this regime was slightly higher than that of the T1N1 treatment.【Conclusion】The N1 nitrogen treatment under elevated CO₂ conditions effectively increased the stem diameter, shoot thickness, chlorophyll content, net photosynthetic rate, stomatal conductance, and water use efficiency of “Ningqi-1,” while reduced the stomatal limit. This treatment also sustained higher yields and mitigated the adverse effects of increased CO₂ levels, making it a more suitable option for cultivation in environments with higher CO₂ concentrations.

Key words: Lycium barbarum‘Ningqi-1’, summer fruit period, nitrogen addition, increase of CO₂ concentration, photosynthetic characteristic

中图分类号:

S718

马冲,陆晖,李运毛,等. 模拟大气CO₂浓度升高与氮添加对宁夏枸杞生长及光合特性的影响[J]. 南京林业大学学报（自然科学版）, 2024, 48(4): 209-218.

MA Chong, LU Hui, LI Yunmao, CAO Bing, ZHU Jinzhong, KANG Yandong. Effects of elevated CO₂ concentration and nitrogen addition in simulated atmosphere on growth and photosynthetic characteristics of Lycium barbarum[J].Journal of Nanjing Forestry University (Natural Science Edition), 2024, 48(4): 209-218.DOI: 10.12302/j.issn.1000-2006.202210041.

图/表 7

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指标 index	处理时间/d time	T1			T2			P
指标 index	处理时间/d time	N0	N1	N2	N0	N1	N2	P_T	P_N	P_T×N
地径/mm ground diameter	45	8.29±0.26 b	8.03±0.15 b	7.09±0.20 c	8.97±0.16 a	7.26±0.04 c	7.99±0.18 b	0.023	0.000	0.000
	60	9.17±0.15 b	8.63±0.05 d	7.56±0.06 f	8.89±0.03 c	9.60±0.21 a	7.87±0.10 e	0.000	0.000	0.000
	75	9.91±0.21 a	8.71±0.10 b	7.80±0.22 c	9.12±0.09 b	9.94±0.41 a	8.07±0.02 c	0.083	0.000	0.000
	90	10.46±0.17 b	9.25±0.28 c	8.31±0.24 c	12.37±0.94 a	11.49±0.47 a	8.81±0.06 c	0.000	0.000	0.048
新梢长/mm shoot length	45	67.33±1.25 cd	84.00±0.82 a	70.67±4.64 c	67.33±1.25 cd	76.00±1.41 b	65.00±2.45 d	0.006	0.000	0.085
	60	74.00±0.82 cd	95.33±1.25 a	83.67±1.70 b	70.33±2.87 d	83.00±1.63 c	75.67±1.70 b	0.000	0.000	0.016
	75	92.33±1.70 c	104.33±1.25 a	97.33±0.94 b	81.00±2.94 e	85.67±2.49 d	76.33±1.25 f	0.000	0.000	0.010
	90	111.33±2.49 b	122.67±2.05 a	84.00±2.45 c	85.67±1.25 c	87.67±1.25 c	84.67±2.87 c	0.000	0.000	0.000
新梢粗/mm shoot thickness	45	3.96±0.09 b	3.75±0.06 b	4.33±0.06 a	3.38±0.12 c	4.56±0.27 a	3.12±0.08 c	0.001	0.000	0.000
	60	4.67±0.09 b	4.46±0.02 c	5.19±0.05 a	4.00±0.12 d	4.81±0.05 b	4.35±0.10 c	0.000	0.000	0.000
	75	5.14±0.08 b	5.25±0.09 b	5.49±0.09 a	4.14±0.08 d	4.85±0.04 c	4.63±0.21 c	0.000	0.000	0.006
	90	4.79±0.02 c	5.31±0.12 b	5.88±0.01 a	4.62±0.27 c	5.42±0.07 b	4.76±0.15 c	0.000	0.000	0.000

指标 index	处理时间/d time	P_T	P_N	P_T×N
叶绿素含量 chlorophyll content	45	0.000	0.031	0.000
	60	0.000	0.000	0.000
	75	0.000	0.000	0.001
	90	0.000	0.000	0.000
净光合速率 net photosynthetic rate	45	0.000	0.031	0.000
	60	0.000	0.615	0.000
	75	0.000	0.000	0.615
	90	0.007	0.028	0.007
蒸腾速率 transpiration rate	45	0.061	0.000	0.000
	60	0.018	0.000	0.010
	75	0.000	0.000	0.003
	90	0.995	0.000	0.001
胞间CO₂浓度 intercellular CO₂ concentration	45	0.000	0.000	0.000
	60	0.000	0.000	0.000
	75	0.000	0.000	0.000
	90	0.000	0.000	0.000
气孔导度 stomatal conductance	45	0.000	0.000	0.000
	60	0.000	0.000	0.000
	75	0.000	0.000	0.000
	90	0.000	0.000	0.055
水分利用效率 water use efficiency	45	0.000	0.000	0.000
	60	0.000	0.000	0.000
	75	0.000	0.000	0.001
	90	0.000	0.000	0.055
气孔限制值 stomatal limit ation value	45	0.000	0.000	0.000
	60	0.000	0.000	0.000
	75	0.842	0.079	0.012
	90	0.000	0.000	0.000

处理 treatment		时刻 o’clock
处理 treatment		9:00	11:00	13:00	15:00	17:00
	N0	10.07±0.62 e	15.33±0.17 c	40.24±0.48 a	17.32±1.64 c	8.6±0.37 b
T1	N1	21.52±2.54 b	21.04±0.76 ab	24.29±2.04 cd	19.63±1.09 cd	10.84±0.56 a
	N2	16.87±0.62 cd	10.85±1.49 d	14.99±1.06 e	24.45±1.47 b	9.47±0.12 b
	N0	16.37±0.69 d	22.43±0.90 a	38.01±1.13 ab	4.25±0.36 d	1.66±0.87 c
T2	N1	28.25±0.81 a	18.84±1.90 b	36.9±1.47 b	24.23±0.09 b	1.22±0.16 c
	N2	19.35±0.69 bc	19.42±2.16 ab	21.08±1.35 d	29.46±0.91 a	1.48±0.50 c
	P_T	0.000	0.000	0.000	0.090	0.000
P	P_N	0.000	0.001	0.000	0.000	0.071
	P_T×N	0.055	0.000	0.000	0.000	0.008

处理 treatment	指标 index	蒸腾速率 transpiration rate	气孔导度 stomatal conductance	净光合速率 net photosynthetic rate	胞间CO₂浓度 intercellular CO₂ concentration	水分利用效率 water use efficiency	气孔限制值 stomatal limit value
正常 normal	地径ground diameter	-0.300	0.101	-0.141	0.743^**	-0.020	-0.559^**
	新梢长度shoot length	0.031	0.618^**	0.423^*	0.544^**	0.081	-0.340^*
	新梢粗度shoot coarseness	0.318	0.755^**	0.191	0.300	-0.406^*	-0.194
	叶绿素含量chlorophyll content	0.292	0.084	-0.156	0.369^*	-0.344^*	-0.348^*
	单株产量yield per plant	0.017	0.493^**	0.379^*	0.367^*	0.03	-0.182
CO₂浓度升高及氮添加 increase of CO₂ concentration and nitrogen addition	地径ground diameter	0.311	0.633^**	0.492^**	0.130	0.383^*	-0.126
	新梢长度shoot length	0.427^**	0.702^**	0.685^**	0.410^*	0.566^**	-0.407^*
	新梢粗度shoot coarseness	0.424^**	0.577^**	0.706^**	0.442^**	0.556^**	-0.442^**
	叶绿素含量chlorophyll content	0.494^**	0.270	0.373^*	0.485^**	0.127	-0.484^**
	单株产量yield per plant	0.376^*	0.492^**	0.397^*	0.443^**	0.251	-0.438^**