Use of sludge from fish ponds as substrate in the production of lettuce (Lactuca sativa) seedlings

Abstract

An ideal and economic substrate for lettuce seedlings varies from region to region depending
on the local availability of alternatives. The objective of this work was to evaluate the effect of
sediment sludge from fish ponds (L) on the production of lettuce seedlings in organic production
system. Five treatments were established composing different substrates: T1 - Exclusive
use of L as substrate, T2 - 50% of L + 50% of coconut coir (PC), T3 - 34% of L + 66% of PC,
T4 - 34% humus (H) + 66% PC, and T5 - 50% H + 50% PC. The experimental design was in
randomized blocks with six blocks and each replicate contained a row of 16 seedlings that were
individually evaluated for height and number of leaves at 26 days after sowing. The uniformity
of the seedlings and the relation height to number of leaves were calculated. The L alone or
added with PC conditioner is a good alternative when evaluated under the aspect of seedlings
growth and uniformity.