不同施氮水平对色素辣椒光合效率的影响

doi:10.6048/j.issn.1001-4330.2022.10.019

摘要/Abstract

摘要：

【目的】研究减氮对辣椒光合效率和产量的影响,分析不同施氮水平下氮素的含量与光合效率和产量的关系。【方法】研究利用盆栽在2个时期设置4个施氮水平:苗期N₁(47.52 Kg/hm²)、N_0.8(38.03 Kg/hm²)、N_0.6(28.50 Kg/hm²)、N₀(0 Kg/hm²);坐果期N₁(79.20 Kg/hm²)、N_0.8(63.36 Kg/hm²)、N_0.6(47.52 Kg/hm²)、N₀(0 Kg/hm²),分析不同处理下辣椒的光合、氮和产量等相关指标。【结果】苗期N_0.6处理下色素辣椒生长指标和光合参数均最大,净光合速率分别较N₁、N_0.8、N₀处理增加了8.6%、9.8%、13.5%;最大羧化速率(V_cmax)增加了7.6%、8.3%、9.3%;最大电子传递速率(J_max)增加了17.1%、18.4%、21.8%。坐果期N_0.8处理下色素辣椒生长指标及光合参数最大,净光合速率分别较N₁、N_0.6、N₀处理升高了10.0%、10.2%、15.4%;V_cmax升高了4.9%、6.3%、13.4%;J_max分别增加了0.6%、15.8%、21.9%。苗期N_0.8处理下色素辣椒产量较N₁、N_0.6、N₀分别增加了1.8%、2.5%、2.8%。坐果期N_0.8处理下色素辣椒产量较N₁、N_0.6、N₀分别增加了6.3%、11.6%、17.6%。随着施氮量的减少,辣椒比叶重(LMA)和光合氮利用效率(PNUE)增加,比叶氮(N_area)则下降;施氮水平对氮素在光合器官中的分配也有影响,氮素在光合系统分配比例随着施氮量的减少逐渐增加,在非光合系统中的分配比例随施氮量的减少而减少。氮素在辣椒叶片光合组分的分配比例与PNUE显著正相关,在非光合组分的分配比例则与PNUE显著负相关。【结论】内色素辣椒苗期营养生长最适宜施氮量为N_0.6处理,而生殖生长最适宜施氮量为N_0.8处理,坐果期则皆为N_0.8处理,即两个时期N_0.8处理皆更利于色素辣椒产量形成。

关键词: 色素辣椒; 光合器官; 氮分配; 光合氮利用效率

Abstract:

【Objective】 In order to clarify the effect of nitrogen reduction on photosynthetic efficiency of pepper, the relationship between nitrogen content and photosynthetic efficiency under different nitrogen reduction levels was analyzed.【Method】 Four nitrogen application levels were set in pots,Seedling period: N₁(47.52 kg/hm²)、N_0.8(38.03 kg/hm²)、N_0.6(28.50 kg/hm²)、N₀(0 kg/hm²);Fruit setting period: N₁(79.20 kg/hm²)、N_0.8(63.36 kg/hm²)、N_0.6(47.52 kg/hm²)、N₀(0 kg/hm²).【Results】 Under the N_0.6 treatment at the seedling stage, the growth index and photosynthetic parameters of pigment pepper were the largest, and the net photosynthetic rate increased by 8.6%, 9.8% and 13.5% compared with the N₁, N_0.8 and N₀ treatments, respectively.The maximum carboxylation rate (V_cmax) increased by 7.6%, 8.3%, and 9.3%.; The maximum electron transfer rate (J_max) increased by 17.1%, 18.4%, and 21.8%.Under the N_0.8 treatment of fruit setting, the growth index and photosynthetic parameters of pigmented pepper were the largest, and the net photosynthetic rate was increased by 10.0%, 10.2% and 15.4% compared with N₁, N_0.6 and N₀ treatments, respectively.V_cmax increased by 4.9%, 6.3%, and 13.4%; J_max increased by 0.6%, 15.8%, and 21.9%, respectively.Under the N_0.8 treatment at the seedling stage, the production of pigmented peppers increased by 1.8%, 2.5% and 2.8% compared with N₁, N_0.6 and N₀, respectively.Under the N_0.8 treatment of fruit setting, the production of pigmented peppers increased by 6.3%, 11.6% and 17.6% respectively compared with N₁, N_0.6 and N₀.Analysis over both periods showed that as nitrogen application decreased, peppers increased in specific leaf weight (LMA) and photosynthetic nitrogen use efficiency (PNUE) and decreased specific leaf nitrogen (Narea); Nitrogen application levels also have an effect on nitrogen distribution in photosynthetic organs, and the proportion of nitrogen in the photosynthetic system gradually increases with the decrease of nitrogen application, and the proportion of nitrogen in non-photosynthetic systems decreases with the decrease of nitrogen application.The proportion of nitrogen in the photosynthetic components of pepper leaves was significantly positively correlated with PNUE, and the proportion of non-photosynthetic components was significantly negatively correlated with PNUE.【Conclusion】 Within the scope of this test, the most suitable nitrogen application rate for the growth of pigmented pepper seedlings was N_0.6 treatment, while the most suitable nitrogen application amount for reproductive growth was N_0.8 treatment, and the fruit setting stage was N_0.8 treatment, that is, the N_0.8 treatment in both stages was more conducive to the formation of pigment pepper yield.

Key words: pigment pepper; photosynthetic organs; nitrogen distribution; photosynthetic nitrogen use efficiency

中图分类号:

S641.3

谢雪果, 袁雷, 王世宁, 沈凌峰, 夏亚辉, 吉雪花. 不同施氮水平对色素辣椒光合效率的影响[J]. 新疆农业科学, 2022, 59(10): 2502-2513.

XIE Xueguo, YUAN Lei, WANG Shining, SHENG Lingfeng, XIA Yahui, JI Xuehua. Effects of Different Nitrogen Application Levels on Photosynthetic Efficiency of Pigmented Peppers[J]. Xinjiang Agricultural Sciences, 2022, 59(10): 2502-2513.

图/表 8

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尿素处理 Nitrogen treatments	氮肥用量N(kg/hm²)
尿素处理 Nitrogen treatments	苗期 seedling period	坐果期 Fruit setting period
N₁(CK)	47.52	79.20
N_0.8(施氮80%)	38.03	63.36
N_0.6(施氮60%)	28.50	47.52
N₀(施氮0)	0	0

尿素处理 Nitrogen treatments	氮肥用量N(kg/hm²)
尿素处理 Nitrogen treatments	苗期 seedling period	坐果期 Fruit setting period
N₁(CK)	47.52	79.20
N_0.8(施氮80%)	38.03	63.36
N_0.6(施氮60%)	28.50	47.52
N₀(施氮0)	0	0

指标 Param eters	氮素处理 Nitrogen treat ments	发育时期 Development stages
指标 Param eters	氮素处理 Nitrogen treat ments	苗期 Seedling stage	坐果期 Fruit setting period
株高 Plant height (cm/plant)	N₁ N_0.8 N_0.6 N₀	29.00±3.0^a 29.40±0.8^a 30.60±2.3^a 20.40±3.2^a	31.74±1.0^ab 32.96±0.5^a 30.58±2.2^bc 29.46±0.2^c
茎粗 stem diameter (mm/plant)	N₁ N_0.8 N_0.6 N₀	5.22±0.07^a 5.57±0.001^a 6.21±0.11^b 5.33±0.05^a	6.70±0.03^a 6.80±0.01^a 5.79±0.01^b 5.48±0.03^c
叶片数 Leaf number (No./plant)	N₁ N_0.8 N_0.6 N₀	38.7±2.3^b 42.0±9.0^b 47.7±12.3^a 23.0±1.0^c	131.2±14.7^b 156.0±1.0^a 150.0±28.50^a 104.4±31.30^c
单叶面积 Leaf area (cm²/plant)	N₁ N_0.8 N_0.6 N₀	14.63±1.35^c 16.75±1.29^b 20.34±0.49^a 13.32±0.35^c	16.76±0.21^b 22.02±0.11^a 21.02±0.25^a 14.62±1.02^c
单叶干重 Single leaf dry weight (g/plant)	N₁ N_0.8 N_0.6 N₀	0.22±0.001^c 0.25±0.001^c 0.31±0.001^b 0.37±0.001^a	0.300±0.001^d 0.426±0.001^c 0.474±0.001^b 0.566±0.001^a
比叶重 LMA (g/m² )	N₁ N_0.8 N_0.6 N₀	150.26±2.69^b 151.11±5.14^b 154.04±1.7^b 280.31±56.15^a	178.96±6.36^d 193.50±9.61^c 225.60±4.88^b 387.09±4.59^a
总叶绿素含量 Chlorophyll (mg/g)	N₁ N_0.8 N_0.6 N₀	1.61±0.001^c 1.82±0.001^b 1.94±0.001^a 1.41±0.001^d	2.36±0.001^b 2.56±0.001^a 2.34±0.001^b 2.09±0.001^c
类胡萝卜素含量 Carotenoids (mg/g)	N₁ N_0.8 N_0.6 N₀	0.14±0.001^c 0.17±0.001^b 0.24±0.001^a 0.18±0.001^b	0.27±0.001^a 0.29±0.001^a 0.28±0.001^a 0.29±0.001^a

指标 Param eters	氮素处理 Nitrogen treat ments	发育时期 Development stages
指标 Param eters	氮素处理 Nitrogen treat ments	苗期 Seedling stage	坐果期 Fruit setting period
株高 Plant height (cm/plant)	N₁ N_0.8 N_0.6 N₀	29.00±3.0^a 29.40±0.8^a 30.60±2.3^a 20.40±3.2^a	31.74±1.0^ab 32.96±0.5^a 30.58±2.2^bc 29.46±0.2^c
茎粗 stem diameter (mm/plant)	N₁ N_0.8 N_0.6 N₀	5.22±0.07^a 5.57±0.001^a 6.21±0.11^b 5.33±0.05^a	6.70±0.03^a 6.80±0.01^a 5.79±0.01^b 5.48±0.03^c
叶片数 Leaf number (No./plant)	N₁ N_0.8 N_0.6 N₀	38.7±2.3^b 42.0±9.0^b 47.7±12.3^a 23.0±1.0^c	131.2±14.7^b 156.0±1.0^a 150.0±28.50^a 104.4±31.30^c
单叶面积 Leaf area (cm²/plant)	N₁ N_0.8 N_0.6 N₀	14.63±1.35^c 16.75±1.29^b 20.34±0.49^a 13.32±0.35^c	16.76±0.21^b 22.02±0.11^a 21.02±0.25^a 14.62±1.02^c
单叶干重 Single leaf dry weight (g/plant)	N₁ N_0.8 N_0.6 N₀	0.22±0.001^c 0.25±0.001^c 0.31±0.001^b 0.37±0.001^a	0.300±0.001^d 0.426±0.001^c 0.474±0.001^b 0.566±0.001^a
比叶重 LMA (g/m² )	N₁ N_0.8 N_0.6 N₀	150.26±2.69^b 151.11±5.14^b 154.04±1.7^b 280.31±56.15^a	178.96±6.36^d 193.50±9.61^c 225.60±4.88^b 387.09±4.59^a
总叶绿素含量 Chlorophyll (mg/g)	N₁ N_0.8 N_0.6 N₀	1.61±0.001^c 1.82±0.001^b 1.94±0.001^a 1.41±0.001^d	2.36±0.001^b 2.56±0.001^a 2.34±0.001^b 2.09±0.001^c
类胡萝卜素含量 Carotenoids (mg/g)	N₁ N_0.8 N_0.6 N₀	0.14±0.001^c 0.17±0.001^b 0.24±0.001^a 0.18±0.001^b	0.27±0.001^a 0.29±0.001^a 0.28±0.001^a 0.29±0.001^a

指标 Parameters	氮素处理 Nitrogen treatments	发育时期Development stages
指标 Parameters	氮素处理 Nitrogen treatments	苗期Seedling stage	坐果期Fruit setting period
叶片全氮含量 Nc(%)	N₁ N_0.8 N_0.6 N₀	4.54±0.28^a 4.24±0.001^b 3.98±0.01^c 1.49±0.001^d	4.48±0.01^a 4.00±0.01^b 2.79±0.01^c 1.33±0.01^d
比叶氮 N_area (g /m² )	N₁ N_0.8 N_0.6 N₀	6.83±0.01^a 6.40±0.01^b 6.13±0.01^c 4.18±0.01^d	8.02±0.01^a 7.77±0.01^b 6.29±0.001^c 5.15±0.001^d
净光合速率 Pn [CO₂μmol/( m²·s)]	N₁ N_0.8 N_0.6 N₀	16.78±0.02^b 16.61±0.01^bc 18.23±0.39^a 16.06±0.001^c	17.42±0.23^b 19.16±0.01^a 17.38±0.19^bc 16.61±0.21^c
光合氮利用效率PNUE [CO₂μmol/(g·s),N]	N₁ N_0.8 N_0.6 N₀	2.46±0.001^c 2.59±0.001^c 2.98±0.02^b 3.85±0.001^a	2.17±0.001^d 2.47±0.001^c 2.76±0.001^b 3.22±0.001^a