不同生长时期收获对甜高粱农艺性状及营养品质的影响

doi:10.3864/j.issn.0578-1752.2020.14.005

摘要/Abstract

摘要：

【目的】甜高粱是重要的饲草作物之一,种植广泛。研究甜高粱不同生长时期的生物产量、营养品质以及饲用价值,可为确定甜高粱作为饲草的适宜收获期提供依据。【方法】以甜高粱杂交种济甜杂2号为研究材料,在济南市历城区和济阳区大田以及东营市盐碱地种植,分别在孕穗期、开花期、乳熟期、蜡熟期和完熟期收获取样,对相关农艺性状和营养品质指标进行比较分析,并对不同生长时期的相对饲用价值进行评价。【结果】济甜杂2号植株高大,历城区和东营市株高在蜡熟期达到最大,分别为440.0和390.0 cm,济阳区在完熟期达到最大为445.9 cm。茎秆是构成济甜杂2号总生物量的主要部分,在孕穗期、开花期、乳熟期、蜡熟期和完熟期茎秆鲜重分别占总鲜重的83.8%、83.3%、78.9%、78.4%和78.5%。随着生育期的推进,从孕穗期到蜡熟期,历城区和东营市总鲜重呈递增趋势,在蜡熟期达到最大,分别为1970.5和1977.5g/plant,在完熟期降低。济阳区从孕穗期到完熟期总鲜重呈递增趋势,最大值为2389.4g/plant;历城区和东营市总干重在蜡熟期达到最大,分别为487.2和469.0g/plant,济阳区总干重在完熟期达到最大为573.5g/plant。环境、生长时期以及环境和生长时期互作效应对株高、叶鲜重、秆鲜重、穗鲜重、总鲜重和总干重有显著影响。中性洗涤纤维含量随着生育期的推进逐渐增加,济阳区和东营市均在孕穗期最小,分别为45.27%和46.33%;酸性洗涤纤维含量也表现出相同的增长趋势,济阳区和东营市在孕穗期最小,分别为29.06%和32.07%。粗蛋白质含量在各个生长时期变化较大,没有明显的变化规律,济阳区在孕穗期最大为6.29%,东营市在开花期最大为6.83%。可溶性碳水化合物含量随着生育期的推进,均在完熟期达到最大,济阳区和东营市分别为14.09%和15.69%。灰分含量随着生育期的推进,济阳区在完熟期达到最大为8.53%,东营市在蜡熟期达到最大为5.36%。环境、生长时期以及环境和生长时期互作效应对中性洗涤纤维含量、酸性洗涤纤维含量、粗蛋白质含量、可溶性碳水化合物含量和灰分含量的影响达到显著性水平。干物质采食量在5个生长时期表现出逐渐降低的趋势,济阳区和东营市在孕穗期最大,分别为2.65%和2.59%,可消化干物质也在孕穗期最大,分别为66.26%和63.92%,相对饲用价值也是在孕穗期最大,在济阳区和东营市分别为136.17和128.35。环境、生长时期以及环境和生长时期互作效应对干物质采食量、可消化干物质和相对饲用价值有显著影响。【结论】甜高粱的生物量、营养品质和相对饲用价值受环境、生长时期以及环境和生长时期互作效应的显著影响。蜡熟期前后收获可获得最大生物量,孕穗期收获干物质采食量、可消化干物质和相对饲用价值最高。但综合考虑生物量、营养品质和青贮品质,乳熟期到蜡熟期是甜高粱的最佳收获时期。

关键词: 甜高粱, 不同生长时期, 农艺性状, 营养品质, 相对饲用价值

Abstract:

【Objective】 Sweet sorghum (Sorghum bicolor (L.) Moench) is one of the most important forage crops and is widely cultivated. Studies on biological yield, nutritional quality and forage value of sweet sorghum at different growth stages could provide theoretical guidance for determining the suitable harvesting time of sweet sorghum as forage. 【Method】 Sweet sorghum hybrid, Jitianza No.2, was used as an experiment material, planted in Licheng and Jiyang District in Jinan, and Dongying Cities, and mowed at booting, flowering, milky, dough and physiologic maturity stages. Agronomic and nutritional quality related traits were analyzed, and relative feed values (RFV) at five growth stages were evaluated. 【Result】 The largest value of plant height of Jitianza No.2 were 440.0 cm and 390.0 cm at dough stage in Licheng District and Dongying City, and 445.9 cm at physiologic maturity stage in Jiyang District. Stem is the main component of total fresh weight (TFW) and occupied 83.8%, 83.3%, 78.9%, 78.4% and 78.5% of TFW at five growth stages, respectively. With development of plant, TFW was gradually increased from boot stage to dough stage and decreased at physiologic maturity stage in Licheng District and Dongying City. The maximum TFW were 1 970.5 g/plant and 1 977.5 g/plant. TFW was increased from boot stage to physiologic maturity stage with the maximum TFW of 2 389.4 g/plant in Jiyang District. Total dry weight (TDW) showed the same change trend as TFW, and the maximum TDW of 487.2 g/plant and 469.0 g/plant were reached at dough stage in Licheng District and Dongying City, and 573.5 g/plant at physiologic maturity stage in Jiyang District. Significant effects by environment, growth stage and interaction between environment and growth stage were identified in plant height, leaf fresh weight, stem fresh weight, panicle fresh weight, TFW and TDW. The content of neutral detergent fiber (NDF) was gradually increased with development of plant and the minimum were 45.27% and 46.33% at booting stage, respectively, in Jiyang District and Dongying City. Acid detergent fiber (ADF) content had a similar trend with NDF and the minimum of 29.06% and 32.07% were found at booting stage in Jiyang District and Dongying City. Crude protein (CP) content varied largely in each growth period, with the highest values of 6.29% at booting stage in Jiyang District and 6.83% at flowering stage in Dongying City. Soluble carbohydrate (SC) content was increased significantly at each growth period and reached the maximum of 14.09% and 15.69% at physiologic maturity stage, respectively, in Jiyang District and Dongying City. Ash content was gradually increased with development of plant and the maximum of 8.53% and 5.36% were reached at physiologic maturity stage in Jiyang District and dough stage in Dongying City. Effects by environment, growth stage and interaction between environment and growth stage were significant in NDF, ADF, CP, SC and ash content. With growth of plant, dry matter intake (DMI) at five growth stages was gradually decreased, and the maximum were 2.65% and 2.59% at booting stage in two environments, respectively. Digestible dry matter (DDM) had the same change trend as DMI and the maximum were 66.26% and 63.92% in Jiyang District and Dongying City. Similarly, the maximum RFV of 136.17 and 128.35 were found at booting stage. Significant effects by the environment, growth stage and interaction between environment and growth stage were found in DMI, DDM and RFV.【Conclusion】Biomass, nutritional quality and RFV of sweet sorghum were significantly affected by environment, harvesting stage and environment-harvesting stage interaction. The largest biomass could be obtained at about dough stage, and the highest DMI, DDM and RFV could be reached at booting stage. However, considering the optimal combination of biomass, nutrient quality and silage quality, the optimum harvesting stage was between milk and dough stage.

Key words: sweet sorghum, different growth stage, agronomic traits, nutritional quality, relative feed value

王海莲,王润丰,刘宾,张华文. 不同生长时期收获对甜高粱农艺性状及营养品质的影响[J]. 中国农业科学, 2020, 53(14): 2804-2813.

WANG HaiLian,WANG RunFeng,LIU Bin,ZHANG HuaWen. Effects of Harvesting at Different Growth Stage on Agronomic and Nutritional Quality Related Traits of Sweet Sorghum[J]. Scientia Agricultura Sinica, 2020, 53(14): 2804-2813.

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环境 Environment	时期 Stage	株高 PH (cm)	叶鲜重 LFW (g/plant)	秆鲜重 SFW (g/plant)	穗鲜重 PFW (g/plant)	总鲜重 TFW (g/plant)	总干重 TDW (g/plant)
E1	S1	415.9±6.5a	260.5±15.8ab	1373.7±31.0ab	—	1664.2±35.3a	371.9±3.8a
	S2	418.1±4.8a	267.9±10.7ab	1421.4±11.6ad	—	1689.3±20.8a	392.9±3.5b
	S3	427.3±6.4abc	275.6±14.7bc	1468.3±31.3cd	122.2±2.5a	1866.1±22.7b	441.6±3.6c
	S4	440.0±2.0b	299.1±20.8c	1521.4±37.3c	150.0±1.2b	1970.5±28.8c	487.2±2.7d
	S5	432.4±3.3c	217.3±13.1a	1363.0±23.0b	169.7±1.8c	1750.0±32.0d	432.3±1.5e
E2	S1	380.9±2.9a	240.4±14.6a	1716.2±19.6 a	—	1956.6±29.6a	430.2±1.4a
	S2	415.6±3.0b	248.1±10.7a	1648.5±27.0b	—	1896.6±30.2a	425.5±1.7b
	S3	433.9±4.2c	304.8±12.0bc	1834.9±20.6c	80.5±1.6a	2220.3±19.6b	525.1±1.5c
	S4	443.6±7.7d	316.9±18.0c	1887.2±28.5d	122.7±3.5b	2326.7±44.9c	551.8±1.9d
	S5	445.9±4.2d	288.2±11.8b	1900.4±33.5d	200.7±1.4c	2389.4±33.0d	573.5±2.2d
E3	S1	360.2±1.6a	319.4±12.7a	1376.3±18.2a	—	1695.8±23.5a	373.0±0.6a
	S2	369.9±1.6b	364.2±12.6b	1373.4±16.2a	—	1737.6±25.4a	386.2±3.2b
	S3	378.8±3.5c	366.4±11.3b	1472.0±30.7b	111.8±1.8a	1950.2±26.8b	458.4±1.7b
	S4	390.0±2.3d	296.2±5.0c	1520.4±18.8b	160.9±2.9b	1977.5±14.7b	469.0±2.4c
	S5	380.3±3.0c	265.0±5.1d	1475.6±17.9c	151.2±2.6c	1891.8±19.8c	456.00±3.5d
E	F值F value	716.58**	110.66**	1683.48**	145.23**	1240.61**	4325.24**
S	F值F value	128.07**	43.17**	113.52**	3581.47**	419.63**	3696.88**
E×S	F值F value	19.09**	37.21**	24.19**	400.55**	47.48**	220.76**

环境 Environment	时期 Stage	叶占比例 Proportion of leaves (%)	秆占比例 Proportion of stem (%)	穗占比例 Proportion of panicle (%)
E1	S1	17.5	82.5	0.0
E2	S1	12.3	87.7	0.0
E3	S1	18.8	81.2	0.0
平均Average		16.2	83.8	0.0
E1	S2	15.9	84.1	0.0
E2	S2	13.1	86.9	0.0
E3	S2	21.0	79.0	0.0
平均Average		16.7	83.3	0.0
E1	S3	14.8	78.7	6.5
E2	S3	13.7	82.6	3.6
E3	S3	18.8	75.5	5.7
平均Average		15.8	78.9	5.3
E1	S4	15.2	77.2	7.6
E2	S4	13.6	81.1	5.3
E3	S4	15.0	76.9	8.1
平均Average		14.6	78.4	7.0
E1	S5	12.4	77.9	9.7
E2	S5	12.1	79.5	8.4
E3	S5	14.0	78.0	8.0
平均Average		12.8	78.5	8.7

环境 Environment	时期 Stage	中性洗涤纤维 NDF (%）	酸性洗涤纤维 ADF (%)	粗蛋白 CP (%)	可溶性碳水化合物 SC (%)	灰分 Ash (%)
E2	S1	45.27±0.21a	29.06±0.05a	6.29±0.065a	9.73±0.044a	5.93±0.56a
	S2	51.53±0.25b	32.72±0.021b	6.18±0.04b	9.30±0.036b	5.53±0.031ba
	S3	56.17±0.091c	35.34±0.046c	5.42±0.085c	12.50±0.02c	5.75±0.021b
	S4	60.53±0.55d	39.44±0.051d	5.57±0.043d	13.79±0.04d	8.33±0.035c
	S5	62.04±0.051e	38.48±0.036e	5.92±0.039e	14.09±0.025e	8.53±0.025c
E3	S1	46.33±0.11a	32.07±0.067a	6.51±0.044a	12.28±0.062a	4.68±0.015a
	S2	51.58±0.45b	32.33±0.091b	6.83±0.043b	12.93±0.065b	5.04±0.025ab
	S3	52.37±0.06c	33.56±0.055c	6.47±0.062a	12.96±0.049b	5.16±0.015b
	S4	55.00±0.2d	34.31±0.076d	6.54±0.074a	13.70±0.026c	5.36±0.021b
	S5	56.63±0.38e	35.43±0.031e	6.32±0.035c	15.69±0.027d	5.34±0.032b
E	F值F value	679.29**	5145.78**	1762.85**	3571.5**	405.16**
S	F值F value	2092.54**	14680.76**	213.2**	1735.34**	134.57**
E×S	F值F value	197.47**	4430.13**	72.75**	238.69**	76.49**

环境 Environment	时期 Stage	干物质采食 DMI (%)	可消化干物质 DDM (%)	相对饲用价值 RFV
E2	S1	2.65±0.012a	66.26±0.04a	136.17±0.56a
	S2	2.33±0.011b	63.41±0.02b	114.46±0.59b
	S3	2.14±0.003c	61.37±0.04c	101.64±0.22c
	S4	1.98±0.018d	58.17±0.04d	89.40±0.75d
	S5	1.93±0.002d	58.92±0.03e	88.35±0.040d
E3	S1	2.59±0.006a	63.92±0.05a	128.35±0.40a
	S2	2.33±0.020b	63.71±0.07b	114.90±1.08b
	S3	2.29±0.003c	62.75±0.04c	111.47±0.20c
	S4	2.18±0.008d	62.17±0.06d	105.15±0.28d
	S5	2.12±0.014e	61.30±0.02e	100.70±0.69e
E	F值F value	511.29**	5145.78**	875.16**
S	F值F value	2493.6**	14680.76**	4342.28**
E×S	F值F value	175.6**	4430.13**	435.6**