复种时密度和品种对光敏型高丹草营养品质及产量的影响

Effects of different densities and varieties on nutrients content and yield of photoperiod-Sensitive sorghum-Sudan hybrids in summer sowing

本试验以光敏型高丹草为试验材料,探讨种植密度及品种对其营养成分及产量的影响。在陇东旱塬麦收后以6.75(45P)、9.75万株/hm2(65P)和12.75万株/hm2(85P)复种海牛、BJM和大卡3个品种。结果表明:品种对各营养成分含量、粗蛋白质(CP)与总可消化营养物(TDN)产量和相对饲喂价值(RFV)均有极显著(P<0.01)影响,CP含量和产量以BJM最高;种植密度对CP、可溶性糖(SS)、酸性洗涤纤维(ADF)及TDN含量、RFV和TDN产量影响均极显著(P<0.01),CP和TDN产量以85P最高;品种和种植密度互作对各营养成分含量和RFV影响均极显著(P<0.01),对CP产量影响显著(P<0.05)。综上所述,以养分产量为主要考虑因素,在黄土高原半湿润偏旱雨养农业区麦收后夏播复种光敏型高丹草的生产模式中,以BJM 12.75万株/hm2种植为最优。

This study was conducted to discuss the effects of different densities and varieties on nutrients content and yield of photoperiod-sensitive sorghum-sudan hybrids in Longdong dryland area in Gansu province.The hybrids of Monster,BJM and Big kahuna（with brown midrib,BMR） were multiple cropped after winter wheat with three densities,67000（45P）,97500（65P）,127500（85P） plants/hm^2.The results showed that among 3 varieties,there were extremely significant difference（P〈0.01） in the content of each nutrient,the yield and relative feeding value（RFV）,BJM had the highest crude protein（CP） content and yield.Among different densities,there were extremely significant difference（P〈0.01） in the CP,soluble sugar（SS）,acid detergent fiber（ADF）,total digestible nutrients（TDN） content,RFV and the TDN yield,the 85 P group had the highest CP and TDN yield.The interaction of variety and planting density had an extremely significant（P0.01） impact on each nutrient content and RFV,while there was a significant（P〈0.05）effect on the CP yield.In conclusion,mainly considering the yield of nutrient,the optimum multiple cropped production model of sorghum-sudan hybrid was BJM with 127500 plants/hm^2 in the semi-humid and droughtrain-farming area of the Loess Plateau in summer.