种植密度和施氮对玉米×墨西哥大刍草杂种饲草产量与饲用价值的影响

Effects of Different Planting Density and Nitrogen Application on Forage Yield and Feeding Value of Zea mays × Z.mexicana Hybrid

采用二因素裂区试验,研究了种植密度和施氮对玉米×墨西哥大刍草杂种饲草产量和饲用价值的影响。结果表明,种植密度、施氮及其交互效应对玉米×墨西哥大刍草杂种饲草产量和饲用价值影响显著。低密度和高密度均降低了饲草产量,较高的施氮量提高饲草产量。饲草的粗蛋白含量、粗脂肪含量、可溶性糖含量、相对饲用价值随着种植密度的降低和施氮水平的升高而升高,酸性洗涤纤维和中性洗涤纤维含量则相反。5种营养成分产量均随密度和施氮量的增加分别呈"低-高-低"和逐步上升的变化趋势。说明在玉米×墨西哥大刍草杂种栽培过程中,可以通过调节种植密度和施氮量,充分利用密氮互作效应,提高饲草产量和饲用价值。在本试验条件下,玉米×墨西哥大刍草杂种种植密度在40 000株/hm2的基础上施氮450 kg/hm2左右是饲草高产优质的合理组合。

The effects of planting density and nitrogen application on the Z.mays ×Z.mexicana hybrid forage yield and feeding value traits were studied by the means of using a split plot experiment with two factors .The results show that effect of density ,nitrogen application and the interactions between them on the forage yield and feeding value traits were significant .The lowest and highest planting could decrease forage yield ,but high nitrogen applica-tion improve forage yield.The crude potein content,ether extract content,water soluble carbohydrate content ,rela-tive feeding value of the Z.mays ×Z.mexicana hybrid were all increased both with the decrease of planting density and the increase nitrogen application level , while acid detergent fiber and neutral detergent fiber content were de-creased .The crude potein , ether extract , water soluble carbohydrate , acid detergent fiber , neutral detergent fiber yields of the Z.mays ×Z.mexicana hybrid with the increase of planting density and nitrogen application which showed the change of "low-high-low"and rising gradually ,respectively .We can adjust planting density and nitrogen rate to take advantage of the interaction between them to improve Z.mays ×Z.mexicana hybrid forage yield and feeding value .In conclusion ,planting at 40 000 plants per hectare and applying 450 kg nitrogen per hectare were best management practices ,based on the results of this study .