Impact Of Cereal-Legume Mixed-cropping And Different Harvesting Stages On Fresh Forage Yield And Quality

Forage plays a vital role in livestock production,as it directly impacts animal nutrition and the quality of meat and milk.Ensuring the availability of sufficient and nutritionally adequate forage is a major challenge in the animal industry.Legumes and cereals are important fodder crops known for their nutritional characteristics,such as higher protein content ration in legumes and greater fiber content in cereals.Integrating cereal and legume crops in mixed cropping systems offers a potential solution to address issues such as low forage nutrition,insufficient fodder availability,unsustainable cultivation practices,and decline soil fertility.This study aimed to investigate the impact of cereal-legume mixed cropping at different harvesting stages on forage biomass production,nutrient compositions,mineral contents,amino acid compositions,and forage quality index.The legume crops used were pea(Pisum sativum)and alfalfa(Medicago sativa),whereas the cereal crops used were wheat(Triticum aestivum)and ryegrass(Lolium multiflorum).Split-plots with randomized block designs and three sample replicates were utlized.The experimental results demonstrated the benefits of intercropping cereal crops with alfalfa in terms of forage productivity and nutrient compositions.The cereallegume intercropping treatments showed higher feed quality when harvested at the flowering stage of cereal crops.Specifically,T8(Baomai 9-alfalfa)exhibited the highest FBY(fresh biomass yield),DMY(dry matter yield)and CPY(crude protein yield).Furthermore,T8(Baomai 9-alfalfa)displayed notable nutrient content,including crude protein(15.65%),ash(11.08%),water-soluble carbohydrate(31.67%),ether extract(2.37%)and crude fiber(35.49%)in the first growing season,crude protein(17.25%),ash(11.89%),water-soluble carbohydrate(31.67%),ether extract(3.37%)and crude fiber(41.47%)in the second growing season.Ryegrass intercropped with alfalfa demonstrated significantly higher neutral detergent fiber(NDF%)and acid detergent fiber(ADF%)throughout the growing seasons.Conversely,cerealpea mixed cropping had a negative impact the forage nutritional contents in the first growing season.The lowest nutritional compositions was observed in the cereal-pea mixed cropping.The lowest nutritional contents were found in cereal sole cropping,particularly in Xiaoyan 17 sole cropping,in the second growing season.Moreover,mixed cropping of ryegrass and alfalfa resulted in superior mineral composition values.T8(Baomai 9-alfalfa)consistently exhibited the highest values for dry matter intake,digestible dry matter,relative feed value,total digestible nutrient,relative forage quality,and quality index.In contrast,sole cropped Xiaoyan 17 had the lowest essential amino acid contents.T8(Baomai 9-alfalfa)treatment demonstrated remarkable amino acid compositions in both growing seasons.Additionally,positive relationships were observed between nutritional indicators such as crude protein,water-soluble carbohydrates,ether extract,crude fiber,ash,neutral detergent fiber,and acid detergent fiber.The study emphasized the significance of harvesting timings,with the flowering stage identified as the optional times for harvesting.Harvesting at the flowering stage resulted in higher fresh biomass production,dry matter yield,nutritional compositions,mineral compositions,and overall forage quality characteristics.Based on chemical compositions and quality analysis,the current study concludes that the flowering stage is the most productive harvesting stage,and that cereal-legume mixed cropping is the most desirable due to its increased quality forage production and nutritional value of the feed stock for the livestock industry.