Effects of mixed seeding of alfalfa and perennial ryegrass on yield and nutritional quality under different nitrogen levels

doi:10.6048/j.issn.1001-4330.2024.07.028

Abstract

Abstract:

【Objective】The effects of mixed sowing of alfalfa and perennial ryegrass on yield and nutritional quality under different nitrogen levels were explored, and the proportion of mixed sowing under the best nitrogen level was screened.【Methods】Alfalfa (WL525HQ) and perennial ryegrass (Toya) were used as materials, and a two-factor split-plot design was used.The nitrogen application rate was the main area, N₀ : no nitrogen application ; N₁ : 20% of the total nitrogen application was base fertilizer, 20% of the top dressing at branching stage, and 60% of the top dressing at budding stage ; N₂ : 20% of the total nitrogen application rate was base fertilizer, 30% of the top dressing at branching stage, and 50% of the top dressing at budding stage ; the mixed sowing ratio of alfalfa (M) and perennial ryegrass (L) was 22.5 kg / hm² and 60.0 kg / hm², respectively.Alfalfa + perennial ryegrass 7∶3 (M₇ + L₃), alfalfa + perennial ryegrass 6∶4 (M₆ + L₄), alfalfa + perennial ryegrass 5∶5 (M₅ + L₅), alfalfa + perennial ryegrass 4∶6 (M₄ + L₆), alfalfa + perennial ryegrass 3∶7 (M₃ + L₇) ; the sowing amount of each plot was sowed according to the percentage of single sowing treatment, with 3 replicates.The yield and nutritional quality of each treatment were compared and analyzed.【Results】Under N₀, N₁ and N₂ nitrogen levels, the hay yield of alfalfa and perennial ryegrass mixed sowing in different stubbles was significantly higher than that of single sowing (P<0.05), and the hay yield of M₅ + L₅ treatment reached 1.06 t / hm².Under N₀, N₁ and N₂ nitrogen levels, CP, DM, RFV, TDN and CP yield content per unit area were significantly higher than those of single sowing (P<0.05), and NDF and ADF were significantly lower than those of single sowing (P<0.05).Under N1 nitrogen level, the CP content of M₇ + L₃ treatment was the highest (P < 0.05), and increased first and then decreased with the increase of the proportion of perennial ryegrass.The CP content of M₅ + L₅ treatment was the highest, and the DM content of M₆ + L₄ treatment was the highest (P< 0.05).The RFV and TDN of M₅ + L₅ treatment were the highest (P < 0.05).The contents of NDF and ADF in M₅ + L₅ treatment were the lowest (P < 0.05), and decreased first and then increased with the increase of the proportion of perennial ryegrass.【Conclusion】The yield, CP, DM, RFV, TDN and crude protein content per unit area of mixed sowing of alfalfa and perennial ryegrass at different nitrogen levels were higher than those of monoculture, and the contents of NDF and ADF were lower than those of monoculture.The optimum ratio of mixed sowing of alfalfa and perennial ryegrass was 5∶5.The annual hay yield reached 1.06 t / hm², the crude protein content was 26.05%, and the NDF and ADF were 26.03% and 26.03%, respectively; The forage yield and nutritional quality of nitrogen treatment were higher than that of the control group, and the nitrogen utilization rate of perennial ryegrass in mixed sowing increased with the increase of its proportion.Among them, 20% of the total nitrogen application rate (100kg / hm²) was the base fertilizer, 20% of the topdressing at the branching stage, and 60% of the topdressing at the budding stage was the best.

Key words: alfalfa; perennial ryegrass; mixed sowing; nutritional quality; yield

摘要：

【目的】研究不同氮素水平下紫花苜蓿与多年生黑麦草混播对其产量和营养品质的影响,筛选出最佳氮素水平下的混播比例。【方法】以紫花苜蓿(WL525HQ)和多年生黑麦草(托亚)为材料,采用两因素裂区设计,以施氮量为主区,N₀:不施氮;N₁:总施氮量20%为基肥、分枝期追肥20%、现蕾期追肥60%;N₂:总施氮量20%为基肥、分枝期追肥30%、现蕾期追肥50%;混播比例为副区单播紫花苜蓿(M)、多年生黑麦草(L),播种量分别为22.5、60.0 kg/hm²;紫花苜蓿+多年生黑麦草7∶3(M₇+L₃)、紫花苜蓿+多年生黑麦草6∶4(M₆+L₄)、紫花苜蓿+多年生黑麦草5∶5(M₅+L₅)、紫花苜蓿+多年生黑麦草4∶6(M₄+L₆)、紫花苜蓿+多年生黑麦草3∶7(M₃+L₇);共计21个处理,每个小区播种量按照单播处理的百分比分别播种,3个重复。比较分析各处理的产量和营养品质。【结果】在氮素水平N₀、N₁、N₂处理下,不同茬次紫花苜蓿与多年生黑麦草混播干草产量均显著高于单播(P<0.05),M₅+L₅处理干草产量达到1.06 t/hm²。在氮素水平N₀、N₁、N₂处理下,粗蛋白CP、干物质DM、饲料相对值RFV、总可滴化养分TDN和单位面积CP产量含量均显著高于单播(P<0.05),中性洗涤纤维NDF、酸性洗涤纤维ADF均显著低于单播(P<0.05);N₁氮素水平下,除M₇+L₃处理CP含量显著最高(P<0.05),且随多年生黑麦草的比例增加呈先增高后降低的趋势,M₅+L₅处理CP含量最高,M₆+L₄处理DM含量显著最高(P<0.05),M₅+L₅处理RFV、TDN最高(P<0.05)。而M₅+L₅处理NDF、ADF含量显著最低(P<0.05),且随多年生黑麦草的比例增加呈先降低后增高的趋势。【结论】不同氮素水平紫花苜蓿与多年生黑麦草混播产量、CP、DM、RFV、TDN、单位面积粗蛋白CP含量均高于单播,NDF、ADF含量低于单播,并在紫花苜蓿与多年生黑麦草混播比例5∶5最优,年干草产量达到1.06 t/hm²,粗蛋白含量为26.05%,NDF、ADF分别为26.03%、26.03%;氮素处理的牧草产量和营养品质要高于对照组,且混播中多年生黑麦草的氮素利用率随着其比例的增高而增高,其中以总施氮量(100 kg/hm²)的20%为基肥、分枝期追肥20%,现蕾期追肥60%最优。

关键词: 紫花苜蓿, 多年生黑麦草, 混播, 营养品质, 产量

CLC Number:

S542+.3

MA Yong, LIU Hui, GAO Hhongmei, KANG Xue, MA Chunhui. Effects of mixed seeding of alfalfa and perennial ryegrass on yield and nutritional quality under different nitrogen levels[J]. Xinjiang Agricultural Sciences, 2024, 61(7): 1793-1804.

马勇, 刘慧, 高红梅, 康雪, 马春晖. 不同氮素水平下紫花苜蓿与多年生黑麦草混播对其产量和营养品质的影响[J]. 新疆农业科学, 2024, 61(7): 1793-1804.

Figures/Tables 6

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处理 Treatments		粗蛋白 CP(%)	干物质 DM(%)	中性洗涤纤维 NDF(%)	酸性洗涤纤维 ADF(%)	饲料相对价值 RFV	总可消化养分 TND	单位面积 CP产量 (unit area)CP (%)
N₀	M	20.27±0.01^Cc	23.35±0.01^Bc	35.31±0.01^Ab	22.79±0.01^Aab	144.54±7.0^Ab	71.12±0.37^Bc	68.97±4.72^Bb
	L	17.65±0.02^Bd	28.90±0.02^Ba	47.31±0.01^Aa	25.48±0.01^Aa	132.59±4.41^Ac	71.19±0.94^Bc	25.80±4.61^Cc
	M₇+L₃	24.21±0.12^Ba	27.59±0.01^Bb	31.92±0.02^Ac	20.27±0.12^Ac	151.13±5.31^Aa	74.49±1.50^Bb	115.71±9.25^Ba
	M₆+L₄	22.32±0.01^Bb	24.98±0.01^Bbc	33.78±0.01^Ab	23.71±0.02^Aab	150.57±5.98^Aa	71.16±1.14^Bc	82.01±2.23^Cb
	M₅+L₅	23.32±0.01^Bab	25.17±0.01^Bbc	28.09±0.01^Bd	17.95±0.01^Bd	154.40±6.00^Aa	75.95±0.75^Bb	81.53±8.09^Bb
	M₄+L₆	23.65±0.01^Aab	26.43±0.03^Babc	24.51±0.07^Ce	15.38±0.03^Ce	153.08±4.2^Aa	78.05±0.54^Aa	74.81±14.25^Bb
	M₃+L₇	22.33±0.02^Ab	23.79±0.01^Bce	27.45±0.01^Cd	15.47±0.01^Ce	153.65±3.91^Aa	78.22±0.95^Aa	87.52±7.31^Bb
N₁	M	25.05±0.01^Ab	27.63±0.01^Ac	30.47±0.03^Bb	19.43±0.02^Ba	145.24±9.73^Ab	75.43±0.76^Ab	119.52±1.49^Ab
	L	17.43±0.03^Ad	33.76±0.01^Aa	48.98±0.02^Ba	19.62±0.05^Ba	130.76±0.30^Ab	72.54±1.40^Ac	48.73±4.78^Ac
	M₇+L₃	26.39±0.05^Aa	27.39±0.03^Bc	30.61±0.02^Bb	18.96±0.02^Bab	151.02±3.11^Aa	75.94±0.91^Ab	164.49±7.12^Aa
	M₆+L₄	24.86±0.02^Ac	30.02±0.02^Aa	30.43±0.01^Bb	20.02±0.03^Ba	150.82±1.31^Aa	74.91±0.48^Ab	175.01±5.47^Aa
	M₅+L₅	26.05±0.01^Aa	25.31±0.02^Bc	26.03±0.03^Cc	15.34±0.04^Cb	154.00±1.78^Aa	78.07±0.70^Aa	168.03±12.21^Aa
	M₄+L₆	22.44±0.03^Ac	19.29±0.03^Cd	29.33±0.02^Bb	18.08±0.02^Bb	152.90±7.36^Aa	74.99±0.66^Bb	112.92±9.31^Ab
	M₃+L₇	22.74±0.01^Bc	27.05±0.02^Ac	31.07±0.02^Bb	20.28±0.02^Ba	150.61±4.00^Aa	74.10±0.30^Bbc	116.01±8.62^Ab
N₂	M	23.06±0.01^Bc	27.86±0.01^Abc	27.65±0.02^Bd	18.64±0.01^Bbc	142.56±3.24^Ab	75.33±0.25^Aab	82.07±9.12^Be
	L	19.00±0.02^Bf	34.23±0.04^Aa	40.64±0.03^Ba	18.04±0.02^Bbc	136.49±3.29^Ac	74.32±0.19^Ab	48.19±8.06^Bf
	M₇+L₃	25.43±0.01^Ba	29.59±0.01^Abc	30.14±0.01^Bc	16.50±0.05^Bc	148.72±4.25^Aab	74.55±047^Bb	183.65±7.01^Aa
	M₆+L₄	22.00±0.03^Bd	28.95±0.02^Abc	29.33±0.01^Bc	19.19±0.01^Babc	150.18±3.91^Aa	74.52±1.04^Ab	121.01±4.43^Bc
	M₅+L₅	23.87±0.01^Ab	28.75±0.01^Abc	30.24±0.01^Ac	20.02±0.01^Aabc	148.12±3.14^Aab	77.83±4.38^ABa	141.85±9.98^ABb
	M₄+L₆	20.24±0.05^Be	31.69±0.01^Aab	35.10±0.01^Ab	23.55±0.03^Aa	152.02±4.77^Aa	70.53±0.90^Cc	106.19±9.99^Ad
	M₃+L₇	24.20±0.01^Ab	26.23±0.01^Ac	35.76±0.02^Ab	21.53±0.01^Aab	152.08±1.31^Aa	73.51±0.37^Bbc	101.03±1.25^ABd

处理 Treatments		粗蛋白 CP(%)	干物质 DM(%)	中性洗涤纤维 NDF(%)	酸性洗涤纤维 ADF(%)	饲料相对价值 RFV	总可消化养分 TND	单位面积 CP产量 (unit area)CP (%)
N₀	M	20.27±0.01^Cc	23.35±0.01^Bc	35.31±0.01^Ab	22.79±0.01^Aab	144.54±7.0^Ab	71.12±0.37^Bc	68.97±4.72^Bb
	L	17.65±0.02^Bd	28.90±0.02^Ba	47.31±0.01^Aa	25.48±0.01^Aa	132.59±4.41^Ac	71.19±0.94^Bc	25.80±4.61^Cc
	M₇+L₃	24.21±0.12^Ba	27.59±0.01^Bb	31.92±0.02^Ac	20.27±0.12^Ac	151.13±5.31^Aa	74.49±1.50^Bb	115.71±9.25^Ba
	M₆+L₄	22.32±0.01^Bb	24.98±0.01^Bbc	33.78±0.01^Ab	23.71±0.02^Aab	150.57±5.98^Aa	71.16±1.14^Bc	82.01±2.23^Cb
	M₅+L₅	23.32±0.01^Bab	25.17±0.01^Bbc	28.09±0.01^Bd	17.95±0.01^Bd	154.40±6.00^Aa	75.95±0.75^Bb	81.53±8.09^Bb
	M₄+L₆	23.65±0.01^Aab	26.43±0.03^Babc	24.51±0.07^Ce	15.38±0.03^Ce	153.08±4.2^Aa	78.05±0.54^Aa	74.81±14.25^Bb
	M₃+L₇	22.33±0.02^Ab	23.79±0.01^Bce	27.45±0.01^Cd	15.47±0.01^Ce	153.65±3.91^Aa	78.22±0.95^Aa	87.52±7.31^Bb
N₁	M	25.05±0.01^Ab	27.63±0.01^Ac	30.47±0.03^Bb	19.43±0.02^Ba	145.24±9.73^Ab	75.43±0.76^Ab	119.52±1.49^Ab
	L	17.43±0.03^Ad	33.76±0.01^Aa	48.98±0.02^Ba	19.62±0.05^Ba	130.76±0.30^Ab	72.54±1.40^Ac	48.73±4.78^Ac
	M₇+L₃	26.39±0.05^Aa	27.39±0.03^Bc	30.61±0.02^Bb	18.96±0.02^Bab	151.02±3.11^Aa	75.94±0.91^Ab	164.49±7.12^Aa
	M₆+L₄	24.86±0.02^Ac	30.02±0.02^Aa	30.43±0.01^Bb	20.02±0.03^Ba	150.82±1.31^Aa	74.91±0.48^Ab	175.01±5.47^Aa
	M₅+L₅	26.05±0.01^Aa	25.31±0.02^Bc	26.03±0.03^Cc	15.34±0.04^Cb	154.00±1.78^Aa	78.07±0.70^Aa	168.03±12.21^Aa
	M₄+L₆	22.44±0.03^Ac	19.29±0.03^Cd	29.33±0.02^Bb	18.08±0.02^Bb	152.90±7.36^Aa	74.99±0.66^Bb	112.92±9.31^Ab
	M₃+L₇	22.74±0.01^Bc	27.05±0.02^Ac	31.07±0.02^Bb	20.28±0.02^Ba	150.61±4.00^Aa	74.10±0.30^Bbc	116.01±8.62^Ab
N₂	M	23.06±0.01^Bc	27.86±0.01^Abc	27.65±0.02^Bd	18.64±0.01^Bbc	142.56±3.24^Ab	75.33±0.25^Aab	82.07±9.12^Be
	L	19.00±0.02^Bf	34.23±0.04^Aa	40.64±0.03^Ba	18.04±0.02^Bbc	136.49±3.29^Ac	74.32±0.19^Ab	48.19±8.06^Bf
	M₇+L₃	25.43±0.01^Ba	29.59±0.01^Abc	30.14±0.01^Bc	16.50±0.05^Bc	148.72±4.25^Aab	74.55±047^Bb	183.65±7.01^Aa
	M₆+L₄	22.00±0.03^Bd	28.95±0.02^Abc	29.33±0.01^Bc	19.19±0.01^Babc	150.18±3.91^Aa	74.52±1.04^Ab	121.01±4.43^Bc
	M₅+L₅	23.87±0.01^Ab	28.75±0.01^Abc	30.24±0.01^Ac	20.02±0.01^Aabc	148.12±3.14^Aab	77.83±4.38^ABa	141.85±9.98^ABb
	M₄+L₆	20.24±0.05^Be	31.69±0.01^Aab	35.10±0.01^Ab	23.55±0.03^Aa	152.02±4.77^Aa	70.53±0.90^Cc	106.19±9.99^Ad
	M₃+L₇	24.20±0.01^Ab	26.23±0.01^Ac	35.76±0.02^Ab	21.53±0.01^Aab	152.08±1.31^Aa	73.51±0.37^Bbc	101.03±1.25^ABd

处理 Treatments	土地当量比(LER)
处理 Treatments	N₀	N₁	N₂
M₇+L₃	1.60±0.23^Ba	1.67±0.36^Ba	1.92±0.33^Aa
M₆+L₄	1.08±0.06^Cb	1.36±0.11^Bb	1.61±0.11^Aab
M₅+L₅	1.55±0.24^Aa	1.61±0.41^Aa	1.72±0.28^Aab
M₄+L₆	1.24±0.17^Aab	1.44±0.48^Aab	1.36±0.10^Ab
M₃+L₇	1.23±0.19^Aab	1.38±0.42^Aab	1.40±0.10^Ab

处理 Treatments	土地当量比(LER)
处理 Treatments	N₀	N₁	N₂
M₇+L₃	1.60±0.23^Ba	1.67±0.36^Ba	1.92±0.33^Aa
M₆+L₄	1.08±0.06^Cb	1.36±0.11^Bb	1.61±0.11^Aab
M₅+L₅	1.55±0.24^Aa	1.61±0.41^Aa	1.72±0.28^Aab
M₄+L₆	1.24±0.17^Aab	1.44±0.48^Aab	1.36±0.10^Ab
M₃+L₇	1.23±0.19^Aab	1.38±0.42^Aab	1.40±0.10^Ab

处理 Treatments		CP(叶) CP (leaves)	CP(茎) CP (stems)	茎(DM) Stem (DM)	叶(DM) Leaf (DM)	吸氮量 Nitrogen uptake	氮素利用率 Nitrogen utilization rate	株高(豆) Plant height (Legumes)	株高(禾) Plant height (Grasses)
N₀	L	13.41±0.21^Bb	7.47±0.21^Be	33.31±0.31^Bb	28.89±0.31^Ca	26.10±1.91^Ba		49.5±0.30^Bc	31.6±1.96^Ab
	M₇+L₃	14.96±0.10^Ab	9.37±0.31^Bd	27.96±0.31^Ad	22.58±0.32^Ac	9.38±2.08^Cc		56.7±2.08^Aa	42.3±2.41^Aa
	M₆+L₄	14.54±0.12^Bb	10.58±0.21^Bc	35.41±0.25^Aa	27.22±0.36^Aab	12.01±1.26^Bbc		55.5±1.50^Aa	26.6±1.91^Ac
	M₅+L₅	14.10±0.13^Ab	10.24±0.51^Bc	32.60±0.23^Bb	27.97±0.88^Aab	9.81±1.06^Cc		54.4±1.21^Aab	26.8±0.20^Bc
	M₄+L₆	17.60±0.50^Aa	12.30±0.52^Ab	23.89±0.24^Ce	22.44±0.84^Cc	14.01±1.46^Bb		56.4±3.24^Aa	34.0±2.64^Ab
	M₃+L₇	16.71±0.51^Aa	13.62±0.41^Aa	33.52±0.65^Ab	26.21±0.56^Ab	14.89±2.35^Cb		51.7±1.61^Bbc	30.7±1.52^Ab
N₁	L	13.59±0.21^Bc	9.44±0.21^Bc	36.39±0.01^Aa	33.82±0.21^Aa	57.96±6.87^Aa		54.2±0.85^Ac	34.7±1.47^Ac
	M₇+L₃	15.03±0.05^Abc	7.76±0.24^Cd	23.08±0.56^Bd	20.26±0.11^Bf	23.23±2.14^Ae	13.89±0.21^Ac	57.7±3.86^Aabc	42.8±1.96^Aa
	M₆+L₄	18.39±0.13^Aa	12.36±0.10^Aa	23.65±0.85^Bd	21.76±0.23^Be	31.22±3.57^Ace	19.21±0.35^Abc	57.3±5.74^Aabc	28.8±1.36^Ad
	M₅+L₅	16.21±0.25^Ab	11.99±0.05^Aa	31.17±0.95^Bc	25.04±0.35^Bd	34.60±3.36^Ac	24.80±0.33^Ab	56.5±3.74^Abc	32.3±2.41^Ac
	M₄+L₆	15.35±0.63^Bbc	10.35±0.09^Bb	32.10±0.23^Abc	26.14±0.25^Bc	38.19±7.22^Abc	24.19±0.72^Ab	61.3±2.08^Aab	38.0±1.73^Ab
	M₃+L₇	15.16±0.23^Bbc	9.85±0.56^Bbc	32.55±0.87^Bb	27.31±0.25^Ab	44.62±1.24^Ab	29.62±0.12^Aa	63.2±0.72^Aa	33.2±1.05^Ac
N₂	L	14.91±0.25^Ace	9.95±0.58^Ab	33.10±0.25^Ba	29.61±0.35^Ba	53.42±7.38^Aa		50.1±0.90^Bc	33.7±1.13^Abc
	M₇+L₃	15.72±0.23^Ac	10.14±0.36^Ae	27.06±0.35^Aa	22.91±0.58^Ad	16.07±3.37^Be	6.73±0.35^Be	59.7±0.57^Aab	39.1±4.41^Aa
	M₆+L₄	18.65±0.35^Aa	12.03±0.58^Af	24.81±0.54^Ba	19.74±0.65^Be	29.30±3.87^Ac	17.29±0.38^Bbc	58.1±1.87^Ab	28.8±0.58^Ac
	M₅+L₅	15.27±0.23^Ac	9.06±0.56^Ba	35.92±0.56^Aa	26.99±0.98^Cb	21.79±2.01^Be	11.99±0.30^Bce	56.3±3.75^Ab	29.3±1.08^ABc
	M₄+L₆	16.98±0.35^Ab	12.14±0.65^Ac	31.39±0.58^Ba	29.18±0.58^Aa	32.20±2.56^bAc	18.20±0.25^Bb	59.5±1.80^Aab	34.7±3.40^Aab
	M₃+L₇	14.12±0.68^Ce	9.35±0.65^Bd	30.03±0.57^Ca	23.81±0.54^Bc	38.77±2.54^b	23.77±0.25^Ba	61.9±0.98^Aa	35.6±3.54^Aab