为研究优质青贮玉米种植的最佳氮肥施用量及最适宜种植密度,提高生产水平及饲草品质,为青贮玉米的实际生产提供数据支撑和技术指导,选择临夏地区主栽的2个青贮玉米品种(S1:铁研53;S2:屯玉168)为试验材料,通过裂区设计,研究3种不同施氮量(A1:0 kg N/hm2;A2:180 kg N/hm2;A3:360 kg N/hm2)和5种不同种植密度(B1:7.5万株/hm2;B2:8.25万株/hm2;B3:9万株/hm2;B4:9.75万株/hm2;B5:10.5万株/hm2)对青贮玉米产量及品质的影响.结果表明:在同一种植密度下,铁研53的株高、鲜草产量、粗淀粉、粗蛋白质含量与施氮量均呈正相关,中性洗涤纤维含量与施氮量差异不显著,酸性洗涤纤维含量呈负相关;其中铁研53在施氮量达到180 kg N/hm2以上时,株高和鲜草产量差异不显著.屯玉168的株高、鲜草产量、粗淀粉、粗蛋白质含量与施氮量均呈正相关,中性洗涤纤维及酸性洗涤纤维含量呈负相关;其中屯玉168在施氮量达到180 kg N/hm2以上时,粗蛋白质和中性洗涤纤维含量差异不显著.在同一施氮量下,铁研53的株高、鲜草产量与种植密度间均呈现先升后降的趋势,粗蛋白质含量与种植密度间呈正相关,中性洗涤纤维含量呈负相关,酸性洗涤纤维含量呈先降后升的趋势;其中铁研53在种植密度达到9.75万株/hm2时,株高、鲜草产量及粗蛋白质含量达到最显著值;在种植密度达到10.5万株/hm2时,粗淀粉和中性洗涤纤维含量达到最显著值;在种植密度达到8.25万株/hm2时,酸性洗涤纤维含量达到最显著值;屯玉168的株高与种植密度间呈正相关,鲜草产量、粗淀粉、粗蛋白质含量与种植密度之间呈现先升后降的趋势,中性洗涤纤维和酸性洗涤纤维含量呈先降后升的趋势;其中屯玉168在种植密度达到9万株/hm2时,各指标均达到最显著值.综合分析表明,铁研53在减氮环境下(180 kg N/hm2)、种植密度9.75万株/hm2时产量及品质综合因素最优,屯玉168在正常氮肥(360 kg N/hm2)、种植密度9万株/hm2时产量及品质综合因素最优.
Effect of nitrogen application rate and planting density on yield and quality of silage maize varieties
To study the best nitrogen application rate and the most suitable planting density of high-quality silage maize,improve the production level and forage quality of silage maize,and provide data support and technical guidance for the actual production of silage maize.Two main silage maize varieties(SI:Tieyan 53;S2:Tunyu 168)in Linxia area were selected as experimental materials.Through split plot design,the effects of three different nitrogen rates(Al:0 kg N/hm2;A2:180 kg N/hm2;A3:360 kg N/hm2)and five different planting densities(B1:75000 plants/hm2;B2:82500 plants/hm2;B3:90000 plants/hm2;B4:97500 plants/hm2;B5:105000 plants/hm2)on the yield and quality of silage maize were studied.The results showed that under the same planting density,plant height,fresh grass yield,crude starch and crude protein contents of Tieyan 53 were positively correlated with nitrogen application rate,neutral detergent fiber content was not significantly different from nitrogen application rate,and acid detergent fiber content was negatively correlated.There was no significant difference in plant height and yield of Tieyan 53 when nitrogen application rate reached 180 kg N/hm2.Plant height,fresh grass yield,crude starch and crude protein contents of Tunyu 168 were positively correlated with nitrogen application rate,while neutral detergent fiber and acid detergent fiber contents were negatively correlated.There was no significant difference in the content of crude protein and neutral detergent fiber in Tunyu 168 when the nitrogen application rate reached 180 kg N/hm2.Under the same nitrogen application rate,plant height,fresh grass yield and planting density of Tieyan 53 showed a trend of first increasing and then decreasing.Crude protein and crude protein contents were positively correlated with planting density,neutral detergent fiber content was negatively correlated,and acid detergent fiber content showed a trend of first decreasing and then increasing.When the planting density of Tieyan 53 reached 97500 plants/hm2,the plant height,grass yield and crude protein content reached the most significant values.When the planting density reached 105000 plants/hm2,the contents of crude starch and neutral detergent fiber reached the most significant value.When the planting density reached 82500 plants/hm2,the acid detergent fiber content reached the most significant value.There was a positive correlation between plant height and planting density of Tunyu 168.Fresh grass yield,crude starch and crude protein contents and planting density increased first and then decreased,while neutral detergent fiber and acid detergent fiber contents decreased first and then increased.Among them,Tunyu 168 reached the most significant value when the planting density reached 90000 plants/hm2.Comprehensive analysis showed that the comprehensive factors of yield and quality of Tieyan 53 were the best under the nitrogen reducing environment(180 kg N/hm2)and the planting density of 97500 plants/hm2,and the comprehensive factors of yield and quality of Tunyu 168 were the best under the normal nitrogen fertilizer(360 kg N/hm2)and the planting density of 90000 plants/hm2.
NETL
NSTL
万方数据
维普
