The researchers conducted a field experiment to see how different types of fertilizers affect the growth and yield of barley in a poplar-based agroforestry system. They tested various combinations of organic and inorganic fertilizers on barley plants. The results showed that using a mix of NPK fertilizer and vermicompost (T8) led to the tallest plants, the most tillers per plant, the longest spikes, the most grains per spike, the highest test weight, and the highest grain and straw yields. For the best economic yield, a combination of NPK fertilizer and compost (T9) was most beneficial, with a benefit-cost ratio of 1:2.08 for barley cultivation.