Organic Fertilization in Lettuce Production

Abstract

Organic fertilization has been growing by about 50% per year in Brazil and worldwide, as it brings several benefits to plant development, improving soil fertility. The objective of this study was to evaluate the effect of using doses of organic compost in seedbeds, in relation to the production of crisp lettuce. The treatments were arranged in a randomized block design, with four treatments and five replications (blocks). The doses were 0, 5, 10 and 20 t ha-1, applied before transplanting the seedlings. The organic compound was  Class – II A type (non-inert), a fertilizer formed by composting waste of animal origin such as rumen, feathers, hatchery waste, pig and cattle farming effluents, leather scrapings, carcass, chicken litter; plant origin such as filter cake, boiler ash, plant biomass, straw and sugarcane bagasse; agro-industrial origin such as grease cleaning and biological sludge. The harvest was performed after 90 days after planting, evaluating the number of leaves, fresh and dry mass of shoot and fresh and dry mass of roots, collecting five plants for each replication. In the results of fresh and dry mass of shoot, as well as for the number of leaves, the best results of mass accumulation were at dose of 5 t ha-1, as with the increase of the doses this accumulation reduced. Organic fertilization is a viable alternative for the cultivation of crisp lettuce. Organic fertilizer at a dose of 5 t ha-1 becomes more efficient among those analysed in this study.