刈割期对燕麦+箭筈豌豆/豌豆混播饲草产量及品质的影响

Effects of Cutting Period on Yield and Quality of Different Oat and Pea Mixed Sowing Combination

为探究西藏高寒地区1年生禾本科和豆科最佳混播比例及刈割期,研究了燕麦与箭筈豌豆、饲用豌豆混播组合在不同刈割期内饲草株高、生产性能和营养价值变化规律,采用灰色关联加权法进行综合评价。结果表明:刈割期可以显著影响饲草产量和品质,随着刈割期的推迟,饲草产量逐渐增加,营养品质降低。不同混播组合干鲜重较单播燕麦略有降低,但高于单播豆科处理。7月25日刈割,饲草干草产量最高,A1B4处理下,即燕麦+箭筈豌豆播量为112.5 kg/hm2+37.5 g/hm2(5∶5),饲草干草产量最高为21903 kg/hm2;A2B4处理下,即燕麦+豌豆播量为112.5 kg/hm2+75.0 kg/hm2(5∶5)时,饲草干草产量最高为17550 kg/hm2。灰色加权关联度评价结果表明,随着刈割期的延长,不同处理下加权关联度逐渐增加。综合加权关联度排名靠前的分别为A1B7、A2B2处理,即燕麦+箭筈豌豆播量为45.0 kg/hm2+60.0 kg/hm2(2∶8)时,燕麦+豌豆播量为157.5 kg/hm2+45.0 kg/hm2(7∶3)时,此时饲草产量最高,营养价值最优。因此,推荐燕麦+箭筈豌豆混播比例为2∶8、燕麦+饲用豌豆混播比例为7∶3,在拉萨周边附近人工建植。

To explore the best mixed sowing ratio and cutting period of annual Gramineae and Leguminosae in alpine region of Tibet,this experiment studied the forage plant height,production performance and nutritional value of mixed sowing combination of Avena(shepHerd)and common vetch(Lanjian No.3)and forage vetch(green bean)in three cutting periods.The grey correlation weighting method was used for comprehensive evaluation.The results showed that the cutting period could significantly affect the yield and quality of forage.With the delay of the cutting period,the yield of for⁃age increased gradually and the nutritional quality content decreased.The dry and fresh weight of different mixed sowing combinations was slightly lower than that of single sowing oat,but higher than that of single sowing legume treatment.On July 25,the highest dry weight of forage was 21903 kg/hm2 when the sowing amount of oat and common vetch was 180.0+15.0 kg/hm2(8︰2).When the sowing amount of oat and pea was 157.5+45.0 kg/hm2(7︰3),the highest dry weight of forage was 17550 kg/hm2.With the delay of cutting period,the crude protein content,crude fibre,crude fat,crude ash,acid detergent fibre,neutral detergent fibre,total nitrogen,total pHospHorus and total potassium of forage grass gradually decreased.The results of grey weighted correlation evaluation showed that the weighted correlation degree increased gradually under different treatments with the extension of cutting period.The A1B7 and A2B2 treatments were ranked in the top of the comprehensive weighted correlation degree.When the sowing amount of oat and common vetch was 45.0 kg/hm2+60.0 kg/hm2(3︰7),and the sowing amount of oat and common vetch was 157.5 kg/hm2+45.0 kg/hm2(7︰3),the forage yield was the highest and the nutritional value was the best,which is suitable for artificial planting near Lhasa.