Fish Hydrolysates Improve Growth of Containerized Lettuce

The use of fish hydrolysates to improve soil fertility and enhance crop yield has gained considerable momentum due to its contribution to agroecological sustainability. Short-term (30-days after transplanting) effects of fish hydrolysates, applied as drench (3 ml of fish hydrolysates at 0, 14 and 24 d after transplanting), on romaine lettuce plants (Lactuca sativa L. cv Heart’s Delight) were evaluated in a growth chamber. Fish hydrolysate treatment improved soil fertility and increased lettuce shoot fresh and dry mass (FM and DM), stem diameter, leaf number and root DM. It also increased leaf chlorophyll a, b and total contents but had no effects on leaf photochemical efficiency, yield and electron transport rate. In addition, fish hydrolysate treatment improved lettuce quality by increasing leaf succulence. The results suggest that fish hydrolysate could be utilized for lettuce organic production to enhance its yield and quality.