Organic versus conventional fertilization: impacts on growth, yield and profitability of lettuce cultivars

Lettuce ( Lactuca sativa L.) is an increasingly popular leafy vegetable in Bangladesh due to its high nutritional value and growing consumer preference for fresh salads. However, productivity remains low compared to major lettuce-producing countries like China and USA, largely because of inadequate cultivar selection and suboptimal nutrient management. The current study was carried out at Gazipur Agricultural University in Bangladesh during the winter to assess the growth performance, yield potential, and economic viability of three lettuce cultivars viz. Green Wave, Grand Rapids, and Iceberg under organic and conventional fertilization systems. Three cultivars and two fertilization techniques were combined in a randomized complete block design with three replicates. Evaluations of yield, profitability, and growth characteristics (plant height, quantity, size, and area of leaves) were observed and analyzed. Results revealed significant interaction effects between cultivar and fertilization method for most growth and yield parameters. The Iceberg cultivar produced the highest marketable yield under conventional fertilization (31.0 t ha -1 ), while organic fertilization enhanced plant height and leaf area in Green Wave. Economic analysis indicated that Iceberg grown under organic fertilization provided the highest benefit-cost ratio (1.84), owing to premium market prices and lower input costs. Overall, the study demonstrates that cultivar choice strongly influences lettuce performance under different fertilization systems, and that organic cultivation of Iceberg lettuce offers a profitable and sustainable option for Bangladeshi farmers.