Technical feasibility of using a geotextile waste material as an alternative to agrofilm for mulching in lettuce

ABSTRACT In semiarid regions, water deficit can be a problem affecting agricultural production. Agrofilm mulches can be used to reduce soil water evaporation as well as to control weeds. The SoilTain DW® geotextile blanket, which is a solid waste material generated in water treatment plants, has the potential to be used for mulching in agriculture. The aim of this study was to evaluate the technical feasibility of using this geotextile waste material as an alternative to different agrofilms for mulching in lettuce under the semiarid conditions of the state of Alagoas, Brazil. Four experiments were carried out in 2020–2021, each with four mulching treatments (white and black polyethylene, geotextile blanket, uncovered soil). Soil surface temperature, plant density, weeds and biometric parameters of the lettuce were assessed and evaluated by univariate and multivariate statistical analyses. Significant treatments × experimental period interactions for all lettuce parameters were observed, except for root biomass. Experiment 2 (winter) presented the most favourable environmental conditions for plant development (mild temperatures) and resulted in an average yield of 25.0 Mg ha−1. In Experiment 1 (autumn/winter), high temperatures (47.9°C) under the black polyethylene reduced plant density (96,800 plants ha−1), though leaf length (16.2 cm) and yield (13.1 Mg ha−1) were not significantly affected. The two canonical variables explained 97.7% of the total variation, forming three similarity groups by Tocher method. All mulches effectively controlled the weeds. Application of the geotextile blanket was concluded to be technically feasible, but it was not recommended for use in the summer when temperatures are high.