Produção e utilização de composto orgânico de resíduos de poda de pata-de-vaca em alface

Abstract

The Pata-de-vaca, Bauhinia forficata, is a tree widely used in urban afforestation, requiring pruning to prevent its excessive growth. Such management results in the production of a large amount of debris that usually ends up in landfills, as its in natura use can have allopathic effects on certain crops. Thus, this work aimed at composting using the pruning residues of Pata-devaca and evaluating the feasibility of using the compost in the production of lettuce seedlings. Composting was carried out using pruning residues, manure from laying hens and cattle. The allopathic effect of the compound on lettuce seed germination, root length, shoot and seedling length was evaluated at different concentrations of aqueous extract (0%, 10%, 25%, 50%, 75% and 100%). The second study was conducted in a greenhouse, where lettuce seedlings were produced using the compound of Pata-de-vaca mixed with Maxfertil® commercial substrate at concentrations of 0%, 10%, 25%, 50%, 75% and 100% of compost. The experiment was carried out for 20 days, with evaluations of germination, dry mass and fresh mass of roots, shoots and the whole plant. The compost of Pata-de-vaca presented better nutritional quality and pH values, C/N ratio more adequate in comparison with the commercial substrate. It also did not present any effect of allelopathy or phytotoxicity on the germination of lettuce seeds, and provided better development of lettuce seedlings with greater accumulation of biomass in relation to the use only of the commercial substrate Maxfertil®.