Avaliação do uso de co-produtos de vermiculita como substrato na produção de mudas de nim (Azadirachta indica A. Juss).

Abstract

This study evaluated the effect of different doses of organic matter and fertilizer PK neem seedlings grown in co-product of vermiculite. The experiment was conducted in 5 L pots in the nursery at the Federal University of Campina Grande. Measurements were made weekly height and diameter after 90 days of experiment. At the end, the seedlings were separated into root, stem and leaves, then the material was placed in an oven and subsequent weighing. The parameters evaluated were: height, diameter, number of leaves, root length, IQD (Dickson quality index), AGR (absolute growth rate) and TDM (total dry mass). The design used in the experiment was the DIC with seven levels of organic matter (OM) (0, 5, 10, 15, 20, 25, 30%) and three fertilization PK (Phosphorus and Potassium) (PK0, PK100, PK300) with four replications. For doses of OM and fertilization was applied polynomial regression grade 2 at 5% of probability. The results of the analysis of variance showed that there were significant differences between all levels of treatment with OM through regression testing on all variables, that for these variables, there was a positive quadratic effect. However, all variables were not statistically different for PK and PK + OM in all parameters evaluated. Thus, the species under study has no requirement for chemical fertilizer in its early growth phase. The AGR values in doses of 10 and 15% of OM, respectively, showed the highest growth rates. Through values DQI and TDM , the dose of 20% of OM in tailings vermiculite is ideal for producing neem seedlings of good quality and vigor.