Use of Coffee Moinha, Commercial Substrate, Carbonized Rice Husk, Coconut Fiber and Eggshell in the Composition of Alternative Substrates for Melon Seedlings Production

Abstract

Research related to the use of agricultural residues as a way to partially or completely replace the commercial substrates has become fundamental, as it reduces the production costs of melon seedlings. The objective of this study was to evaluate the growth variables of melon seedlings grown on substrates composed of carbonized rice husk, coconut fiber, eggshell, increasing levels of coffee moinha, and decreasing commercial substrate substitution to the use of commercial substrate alone. The experiment was carried out in a completely randomized design, with five treatments and ten replicates, of which four treatments were used increasing proportions of moinha and decreasing amounts of commercial substrate (0/40, 10/30, 20/20, 30/10%) as well as fixed proportions of carbonized rice husk (40%), coconut fiber (15%), and egg shell (5%) and the fifth treatment used Bioplant® commercial substrate (control). At 19 days after sowing, the electrical conductivity of the substrates, dry masses of the root system and above-ground part, plant height, stem diameter, and number of leaves were evaluated. The alternative substrate containing proportions of 20% moinha, 20% commercial substrate, 40% carbonized rice husk, 15% coconut fiber, and 5% egg husk is recommended for the production of melon seedlings of the "yellow-type" cultivar seeded in 200-cell styrofoam trays.