海河低平原区施氮磷肥对高丹草生产性能及饲用品质的影响

为探讨海河低平原区施氮磷肥对高丹草(Sorghum bicolor×S.sudanense)生产性能及饲用品质的影响,确定合理的施肥量,研究以冀草2号高丹草为试验材料,采用大田小区栽培法,测定并分析了不同氮磷施肥处理下(N:0、90、180、270、360、450kg·hm~(-2);P:0、45、90、135、180、225kg·hm~(-2))高丹草产量性状、饲用品质以及土壤养分等相关指标的变化。结果表明,随着氮磷施肥量的增加,不同氮肥处理下以N270P180(N:270kg·hm~(-2),P:180kg·hm~(-2))水平的全年干草产量显著高于未施肥对照(P0.05),而不同磷肥处理下的全年干草产量与对照无显著差异(P0.05)。高丹草粗蛋白含量、酸性洗涤纤维、中性洗涤纤维、糖锤度含量以及相对饲用价值在不同氮磷施肥处理间无显著差异(P0.05),但施氮会显著增加硝态氮含量,其硝态氮含量平均比对照增加了62.6%。不同氮肥处理下土壤全氮、碱解氮含量与对照无显著差异(P0.05);不同磷肥处理下土壤速效磷含量高于或显著高于对照。综合分析得出,海河低平原区高丹草合理的施肥量为,N:180~270kg·hm~(-2),P_2O_5:90~135kg·hm~(-2)。

Effects of nitrogen and nhosphate fertilizer application on production performance and forage quality for Sorghum bicolor×S.sudanense in Haihe lowland plain

This study analyzed the effects of nitrogen and phosphate fertilizer application on production performance and forage quality for Sorghum bicolor×S.sudanense in Haihe lowland plain.In this study, we conducted a small-plot field experiment in which 'Jicao 2' was used as experimental material, and analyzed grass yield, forage quality, and soil fertility under N and P fertilizer treatment(N:0, 90, 180, 270, 360, 450 kg·ha-1;P: 0, 45, 90, 135, 180, 225 kg·ha-1).Our results showed that the total dry yield at the N270P180(270 kg·ha-1 N fertiler, 180 kg·ha-1 P fertiler) level was significantly higher than the yield of a control group.However, there was no significant difference in total dry yield from different phosphate fertilizer levels and the control.There were also no significant differences in content of crude protein, acid detergent fiber, neutral detergent fiber, brix, or relative feed value under the nitrogen and phosphate fertilizer treatment, whereas the average of content of nitrate-N was increased 62.6% under nitrogen fertilizer treatment when compared with the control.There were no significant differences in the contents of total N or available N at different levels of nitrogen fertilizer and the control, and the content of available P was higher or significantly higher than CK under phosphate fertilizer treatment.We posit that the optimal fertilizer levels for planting Sorghum bicolor×S.sudanense in Haihe lowland plain are N at 180~270 kg·hm-2 and P2O5 at 90~135 kg·hm-2.