Desenvolvimento de mudas de maracujazeiro-amarelo em função de formulações de substratos à base de insumos orgânicos

Abstract

The cultivation of passion fruit is extensive in Brazil. Its fruit is of expressive nutritional quality and source of income for several farmers. However, the low technological level used in its cultivation in the Amapá state reduces quality and production. The objective of this study was to evaluate the growth of yellow passion fruit seedlings as a function of substratum formulations based on organic matter as well as açaí seed, bovine manure and bubaline. The experiment was carried out in a protected environment at the Federal University of Amapá, Campus Mazagão, Amapá, until the plants were able to transplant. The treatments were constituted by seven formulations of substrates: S1- Biomix commercial substrate; S2- bovine manure; S3- bubaline manure; S4- 100% organic compound based on açaí seed; S5 - 50% soil + 50 bovine manure; S6- 50% soil + 50% bubaline manure and S7-50% soil + 50% fresh açaí seed. The experimental design was completely randomized, with four replications and one useful plant per plot. The sowing was carried out by placing 2 seeds per container using BRS Sol seeds. The substrates were irrigated and maintained at a humidity next to the field capacity. At 35, 42, 49 and 56 days after sowing, plant height, stem diameter, number of leaves emitted, leaf area and relative growth rates were evaluated and, at the end of the experiment, the biomass production of plants as a function of dry matter of root, stem and leaves and total phytomass by weighing the material in balance with an accuracy of 0.001 g. It was also verified the specific leaf area, leaf weight ratio and root/part ratio. The data were submitted to analysis of variance (F test up to 5% probability) and, when significant, averages grouping test (Scott-Knott, p≤0.05) was applied. The substrates based on bubaline and bovine manure promoted a higher growth of the seedlings, whereas those constituted by açaí or by commercial substrate were unsatisfactory to the development of the yellow passion fruit plants during the seedling development