青贮玉米和饲用油菜间作对饲草作物产量和品质的影响

Effect of Intercropping of Silage Corn and Forage Rape on Forage Crop Yield and Quality

为确定青贮玉米与饲用油菜最佳的间作比例及收获时期,以青贮玉米德美亚1号和饲用油菜华杂62号为试验材料,研究不同种植模式[青贮玉米单作(Ⅰ)、饲用油菜单作(Ⅱ)、青贮玉米与饲用油菜2∶4间作(Ⅲ)、青贮玉米与饲用油菜2∶2间作(Ⅳ)]、收获时期[8月20日(A1)、8月30日(A2)、9月10日(A3)、9月16日(A4)]、混贮比例[青贮玉米与饲用油菜1∶1(B1)、1∶2(B2)、2∶1(B3)]对2种饲草作物产量、品质的影响。结果表明,青贮玉米和饲用油菜不同间作比例种植不影响2种作物的生育进程,会降低青贮玉米株高、SPAD值和光合势,对饲用油菜生长发育影响不显著。Ⅰ处理玉米产量显著大于其他处理,于A4时期收获可获得最高产量,达到28.27 t/hm^(2);不同收获期,Ⅰ处理玉米平均产量为20.75t/hm^(2)。Ⅱ处理在A3时期收获,油菜产量最高,为11.24 t/hm^(2)。不同间作处理均在A4时期收获产量最高,A3时期次之,两者差异不明显。随着收获时期推迟,粗蛋白、脂肪、淀粉和总可消化养分含量总体上均呈先上升后下降的趋势,均以A3时期收获最高。在A3时期收获,Ⅲ-B2处理粗蛋白含量最高,为12.5%;脂肪含量最高,为12.6%,较Ⅰ处理高2.32倍;淀粉含量最高,为23.81%,较Ⅰ处理高6.44倍;总可消化养分含量最高,达75.0%,比Ⅰ处理增加44.2%;泌乳净能、维持净能和增质量净能均最大,分别为1.71%、1.84%和1.21%。综上,在冀西北地区,最佳收获时期为9月16日,青贮玉米单作处理产量最高,青贮玉米与饲用油菜2∶4间作处理次之,青贮玉米与饲用油菜1∶2混贮品质最优,推荐青贮玉米与饲用油菜2∶4间作并1∶2混贮。

To determine the optimal intercropping ratio and harvest period of silage corn and forage rape,the silage corn Demeiya 1 and forage rape Huaza 62 were used as materials,and the effects of different planting modes[monoculture of silage corn(Ⅰ),monoculture of forage rape(Ⅱ),2∶4 intercropping of silage corn and forage rape(Ⅲ)and 2∶2 intercropping of silage corn and forage rape(Ⅳ)],harvest time[August 20th(A1),August 30th(A2),September 10th(A3)and September 16th(A4)]and mixed storage ratio[silage corn and rapeseed with 1∶1(B1),1∶2(B2)and 2∶1(B3)]on the yield and quality of two forage crops were studied.The results showed that different intercropping ratios of silage corn and forage rape did not affect the growth process of the two crops,but decreased the plant height,SPAD value and photosynthetic potential of silage corn,and had no significant impact on the growth and development of forage rape.The corn yield of treatmentⅠwas significantly higher than that of the other treatments,and reached the highest of 28.27 t/ha at harvest time of A4.The average yield of treatmentⅠwas 20.75t/haat different harvest time.The treatmentⅡhad the highest yield of forage rape of 11.24 t/ha at harvest time of A3.The treatments with different intercropping ratios had the highest yield at harvest time of A4,followed by A3,and the difference between the two harvest time was not obvious.As the harvest time was postponed,the contents of crude protein,fat,starch and total digestible nutrient generally showed a trend of first increasing and then decreasing,with the highest at harvest time of A3.At the harvest time of A3,theⅢ-B2 treatment had the highest crude protein content of 12.5%;had the highest fat content of 12.6%,which was 2.32 times higher than that of treatmentⅠ;had the highest starch content of 23.81%,which was 6.44 times higher than that of treatmentⅠ;had the highest total digestible nutrient content of 75.0%,which was 44.2%higher than that of treatmentⅠ;had the highest net energy for lactation,maintenance and weight gain,which were 1.71%,1.84%and 1.21%,respectively.In summary,in the northwest region of Hebei Province,the best harvest time is September16th;the yield of silage corn monoculture treatment is the highest,followed by 2∶4 intercropping treatment of silage corn and forage rape;the quality of silage corn and forage rape mixed with a ratio of1∶2 is the best.It is recommended to intercrop silage corn and forage rape with a ratio of 2∶4 and mix them with a ratio of 1∶2 for storage.