不同前作处理及后作饲用玉米种植密度对玉米饲草生产性能和品质的影响

为筛选出适用于西南地区“多花黑麦草(Lolium multiflorum)—饲用玉米(Zea mays)”轮作系统最佳种植组合,本研究采用双因素裂区试验设计,主因素为饲用玉米不同种植密度,副因素为不同多花黑麦草+燕麦前作混播组合,测定饲草生产性能和品质相关指标。结果表明:“多花黑麦草+燕麦”前作混播组合及后作青贮玉米种植密度的交互效应对玉米的干物质产量、粗蛋白产量、酸性洗涤纤维含量等指标有显著的影响(P<0.05);利用熵权法计算饲用玉米产量和营养成分权重,再利用灰色关联法综合评价轮作系统结果表明,前作单播燕麦(Y₀),后作饲用玉米种植密度为78 400株·hm^-2(D₁)时,后作玉米的总饲草产量及营养品质表现最优;前作组合为100%多花黑麦草+25%燕麦(M₁)和后作饲用玉米种植密度(D₁)组合下“多花黑麦草-饲用玉米”系统总饲草产量最高,可为西南地区的“多花黑麦草-饲用玉米”轮作系统推广可利用的组合。

Effects of Different Preceding Combination and Planting Density on Production Performance and Quality of Forage Corn

To select the appropriate Corn-Italian ryegrass rotation system(CIRS)combination in southwestern China,we adopted a two-factor split area experiment design to measure production performance and quality of forage,taking different planting density of the forage corn as the main factor and the different mixed sowing combination of preceding ryegrass and oat as the secondary factor.The result revealed a significant interaction effects of mixed sowing and planting density on dry matter content,crude protein yield and acid detergent fiber content of forage corn(P<0.05).The entropy weight analysis was performed to calculate the weight of forage corn yield and nutrient components,and then grey correlation method was used to evaluate the CIRS system comprehensively.The following results indicated that,the forage yield and nutritional quality of forage corn were reached a peak with the preceding combination of 100% oat(Y₀)and the planting density of 78400 plants·hm^-2(D₁).The highest total forage yield of CIRS,however,was found in treatment with 100% annual ryegrass+25% oat(M₁)and sowing density of forage corn(D₁).This study can provide a technical reference for the popularization and utilization of CIRS in southwestern China.