行距和密度对籽粒饲用高粱产量和品质的影响

Effects of Row Spacing and Plant Density on Grain Yield and Quality of Grain-Feeding Sorghum

【目的】阐明不同行距和密度对籽粒饲用高粱生长、产量形成、品质及氮磷钾吸收的影响,明确山西农牧交错带饲用高粱适宜的栽培模式,为籽粒饲用高粱栽培技术提供理论依据。【方法】以籽粒饲用高粱新品种辽夏梁1号为材料,于2018和2019年开展田间试验。试验共3个行距,分别为30、50和60 cm,每个行距设4个密度,分别为13.5×10^(4)、16.5×10^(4)、19.5×10^(4)和22.5×10^(4)株/hm^(2),分析不同行距和密度及其交互对抽穗期株高、生物量和养分积累量,收获期产量、养分累积量和品质等影响。【结果】行距和密度及其交互作用显著影响饲用高粱的生长、养分吸收、产量形成和籽粒品质。增加种植密度,抽穗期株高、生物量和养分积累量增加,但抽穗后生物量、收获期生物量和养分积累量以及产量在50和60 cm行距下,随密度增加先增加后降低。产量与收获期生物量、氮积累量及抽穗后生物量显著正相关。50 cm行距下的平均产量、抽穗后生物量、收获期氮磷积累大于60和30 cm行距;行距50 cm、密度16.5×10^(4)株/hm^(2)的组合收获期生物量和氮积累量均较高,分别比各处理平均生物量和氮积累量提高3.6%—12.8%和3.6%—18.6%,同时产量也最高,两年分别可达10814和12434 kg·hm^(-2)。籽粒中淀粉和蛋白质含量随密度增加呈降低的趋势,但行距对其影响较小;单宁含量随密度增加显著增加,随行距增加也逐渐增加,行距和密度对饲用高粱籽粒单宁含量的影响大于淀粉和蛋白质。行距为50 cm、密度为16.5×10^(4)株/hm^(2)处理的单宁含量与平均含量相当。【结论】增加生育期内氮素吸收,提高抽穗后生物量、保障收获期生物量是提高产量的关键。饲用高粱在不同行距下合理调整株距可以提高产量,但影响籽粒品质,尤其是单宁含量,综合饲用高粱产量和品质,行距50 cm、密度16.5×10^(4)株/hm^(2)的组合可作为雁门关农牧交错带(辽夏梁1号)的推荐种植方式。

【Objective】This study was conducted to clarify effects of different row spacings and planting densities on the development,yield,grain quality and NPK(nitrogen,phosphorus and potassium)accumulation of grain-feeding sorghum,and to identify the optimal cultivation mode in agro-pastoral ecozone of Shanxi,so as to provide the theoretical basis for the grain-feeding sorghum cultivation.【Method】A new grain-feeding sorghum variety Liaoxialiang No.1 was selected for this study.Field experiments were conducted during 2018 and 2019.Three row spacings were set,i.e.30,50,and 60 cm,respectively.And there were four planting densities(13.5×10^(4),16.5×10^(4),19.5×10^(4) and 22.5×10^(4) plants/hm^(2))at each row spacing.The plant height and biomass at heading stage,grain yield,NPK accumulation at harvest and grain quality in different row spacings and planting densities were analyzed.【Result】There were significantly effects of row spacing,planting density and their interaction on the grain-feeding sorghum growth,nutrient accumulation,grain yield and quality.As plant density increased,the plant height,biomass and NPK accumulation at heading stage were increased.However,the biomass produced after heading,biomass and NPK accumulation at harvest,along with yield,increased first and then decreased with the increase of density under row spacing with 50 and 60 cm;Actually,the grain yield of feeding sorghum was positively correlated with biomass and N accumulation at harvest and the biomass produced after heading.The average grain yield,N and P accumulation and biomass after heading in row spacing of 50cm were higher than those of 60 and 30 cm.Among the 12 treatments,the treatment with row spacing of 50 cm,planting density of 16.5×10^(4) plants/hm^(2) had improved biomass and N accumulation at harvest,which were increased by 3.6%-12.8%and 3.6%-18.6%,respectively,relative to the average value of the total 12 treatments.The grain yield with row spacing of 50 cm and planting density of 16.5×10^(4) plants/hm^(2) was the highest among all treatments,and they were 10814 kg·hm^(-2) in 2018 and 12434 kg·hm^(-2) in 2019,respectively.Starch and protein content of grain decreased with planting density increasing,but the influence of row spacing variation on them were less.Grain tannin content was significantly increased with planting density adding,while the row spacing increase also promoted tannin content.The influence of row spacing and planting density on tannin content was obvious,compared with those on starch and protein.Those treatments with row spacing of 50 cm and density of 16.5×10^(4) plants/hm^(2) had similar tannin content with the average value of different treatments.【Conclusion】Both N accumulation and biomass production after heading were important for high grain yield of feeding sorghum.The appropriate plant spacing under different row spacings could improve feeding sorghum grain yield,but affect grain quality,especially the tannin content.Row spacing of 50 cm and density of 16.5×10^(4) plants/hm^(2) was recommended in agro-pastoral ecozone in Shanxi(with variety of Liaoxialiang No.1)in terms of grain yield and quality of feeding sorghum.