Invasive aquatic plants as a mixed substrate with Red Ferralitic soil in vegetable seedbeds

The composition of the substrates in the vegetable seedbed phase is important for subsequent transplanting. The aim of this study was to evaluate the use of dry mass of the invasive aquatic plants Pistia stratiotes L. and Eichhornia crassipes (Mart.) Solms as a substrate mixed with Red Ferralitic soil for seedbeds of tomato and pepper. To plant tomato and pepper seeds, 300 alveoli were prepared with a mixture of Red Ferralitic soil with different proportions of dry mass of P. stratiotes (0.5% and 1.0%) and E. crassipes (2.0% and 4.0%). At 28 and 40 d after sowing, 30 seedlings per treatment were selected and the average length and diameter of the stem and primary root (cm) were measured. The Dickson quality index was determined in order to select the best treatment. The average stem length was greater in seedlings treated with P. stratiotes (0.5%) and E. crassipes (2.0%) and the diameter was greater in tomato seedlings treated with P. stratiotes (1.0%) and pepper seedlings with P. stratiotes (0.5%); this showed significant differences from the rest of the treatments. The maximum length and diameter of the primary root varied between treatments for both vegetables. The best treatments for the initial growth of tomato and pepper were those when Red Ferralitic soil and dry mass of P. stratiotes (0.5% and 1.0%) and E. crassipes (2.0%) were used as a mixed substrate.