施肥对科尔沁沙地苜蓿产量与品质的影响

Effects of fertilization on yield and quality of alfalfa in Horqin sand land

摘要:

为探索科尔沁沙地紫花苜蓿的施肥技术,设置N₀(不施氮)、N₄₅(45 kg/hm2N)和N90(90 kg/hm2N)3个氮素水平;P₀(不施磷)、P₉₀(90 kg/hm2P₂O₅)、P₁₈₀(180 kg/hm²_P2O₅)和P270(270 kg/hm² P₂O₅)4个磷素水平;K0(不施钾)、K₁₀₀(100 kg/hm²K₂O)、K₂₀₀(200 kg/hm²K₂O)和K300(300 kg/hm²K₂O)4个钾素水平,采用完全随机区组试验设计,研究了不同氮、磷、钾肥施用量组合对紫花苜蓿产量和品质的影响,结果表明:(1)茎叶比、干鲜比在不同氮磷钾处理下无显著性差异,而N₄₅(45 kg/hm²N)处理可以显著提高苜蓿株高和苜蓿产量,全年总产量从12.21 t/hm²增至13.19 t/hm²;(2)磷钾肥的施用均会显著提高紫花苜蓿品质,而施氮会显著降低第1茬、第3茬中紫花苜蓿粗蛋白含量(P＜0.05),而显著提高第2茬紫花苜蓿粗蛋白含量;(3)与不施肥相比,在第1茬中,P₁₈₀(180 kg/hm²P₂O₅)处理下紫花苜蓿粗蛋白含量最高,从18.22%提高至20.11%;而在第2茬中,N₉₀P₂₇₀K₃₀₀(90 kg/hm²N,270 kg/hm²P₂O₅,300 kg/hm²K₂O)处理下紫花苜蓿粗蛋白含量为25.13%,显著高于对照组的22.94%;同样地,在第3茬中,P₂₇₀K₂₀₀(270 kg/hm² P₂O₅,200 kg/hm² K₂O)处理下紫花苜蓿粗蛋白含量为29%,显著高于对照组的25.87%;(4)氮磷钾的施用可以显著提高苜蓿植株磷的含量,氮、钾的施用会显著提高苜蓿钾的含量。综上所述,在缺磷少氮低钾科尔沁沙地苜蓿施肥最佳氮磷钾组合为N₄₅P₂₇₀K₂₀₀。

Abstract:

In order to explore the fertilization technology of alfalfa in Horqin sandy land,three nitrogen levels of N0(no nitrogen application),N₄₅ (45 kg/hm² N) and N₉₀ (90 kg/hm² N),four phosphorus levels of P₀(no phosphorus application),P₉₀ (90 kg/hm² P₂O₅),P₁₈₀(180 kg/hm² P₂O₅) and P₂₇₀ (270 kg/hm² P₂O₅),and four potassium levels of K₀ (no potassium application),K100 (100 kg/hm2 K2O),K200(200 kg/hm2 K2O) and K300(300 kg/hm² K₂O) were set in this experiment,respectively.Random complete block design was used to study the effects of different combinations of nitrogen,phosphorus and potassium fertilizer on the yield and quality of alfalfa.The results showed that: There was no significant difference in stem/leaf ratio and dry/fresh ratio under different NPK treatments.However,N₄₅ (45 kg/hm² N) treatment with low nitrogen level could significantly improve alfalfa plant height and yield,and the annual total yield increased from 12.21 t/hm² to 13.19 t/hm².In addition,fertilization can significantly affect the quality of alfalfa.The application of phosphorus and potassium fertilizer can significantly improve the quality of alfalfa.Nitrogen application also can significantly reduce the crude protein content of alfalfa in the first and third stubble (P＜0.05),while significantly increase the crude protein content of alfalfa in the second stubble.Moreover,compared with no fertilization,the content of crude protein in alfalfa was the highest under the treatment of P₁₈₀(180 kg/hm2 P₂O₅) in the first crop,which increased from 18.22% to 20.11%.In the second crop,the crude protein content of alfalfa treated with N90P270K300 (90 kg/hm2 N,270 kg/hm² P₂O₅,and 300 kg/hm² K₂O) was 25.13%,significantly higher thm²n that of the control group (22.94%).Similarly,in the third crop,the crude protein content of alfalfa treated with P₂₇₀K₂₀₀ (270 kg/hm² P₂O₅,200 kg/hm² K₂O) was 29%,significantly higher thm2n thm2t of the control group (25.87%).In addition,the application of nitrogen,phosphorus and potassium can significantly increase phosphorus content of alfalfa,and the application of nitrogen and potassium can significantly increase potassium content of alfalfa.In conclusion,the optimal combination of N₄₅P₂₇₀K₂₀₀ for fertilization of alfalfa in horqin sandy land is considered in this study.