施肥对天然草地产量、青贮品质及黄曲霉毒素B1含量的影响OA

In order to explore an optimal fertilization strategy in alpine pastoral area,six fertilization treatments were established:control(CK);organic fertilizer alone(5 250 kg/hm2);organic fertilizer(4 200 kg/hm2)combined with inorganic fertilizer(urea 45.6 kg/hm2,superphosphate 87.45 kg/hm2);organic fertilizer(5 250 kg/hm2)combined with biofertilizer(75 kg/hm2);organic fertilizer(4 200 kg/hm2)combined with inorganic fertilizer(urea 45.6 kg/hm2,superphosphate 87.45 kg/hm2)and biofertilizer(75 kg/hm2);and organic fertilizer(4 200 kg/hm2)combined with inorganic fertilizer(urea 45.6 kg/hm2,superphosphate 87.45 kg/hm2),biofertilizer(75 kg/hm2),and micronutrient fertilizer(450 mL/hm2).Forage yield was measured at the full flowering stage,and natural grass was ensiled for 60 days to determine the nutrient composition,fermentation characteristics,and aflatoxin B1(AFB1)content of the silage.The results showed that the fertilization treatments significantly increased forage yield compared with CK(P<0.05),whereas no significant improvement in forage quality was observed.The combined application of organic fertilizer,inorganic fertilizer,biofertilizer,and micronutrient fertilizer,as well as the combination of organic fertilizer,inorganic fertilizer,and biofertilizer,improved the silage quality of natural grass.Among these,the treatment with organic fertilizer,inorganic fertilizer,biofertilizer,and micronutrient fertilizer exhibited the best performance,with water-soluble carbohydrates and lactic acid content increasing by 74.36%and 15.33%,respectively,compared with CK(P<0.05),while neutral detergent fiber,acid detergent fiber,ammonia nitrogen content,and pH decreased by 17.80%,18.39%,65.67%and 4.04%,respectively.In addition,fertilization treatments significantly affected AFB1 content in the silage(P<0.05),with detected values ranging from 8.33 to 11.81 μg/kg,all below the national safety standard for feed.Comprehensive evaluation indicated that the combined application of organic fertilizer silage,inorganic fertilizer,biofertilizer,and micronutrient fertilizer achieved the best utilization of forage.This strategy is recommended for promotion and application in alpine pastoral areas based on local conditions.