Evaluation of the effects of plant growth promoting bacteria on the absorption of potentially toxic elements in Opuntia ficus-indica crops irrigated with wastewater

Abstract

Agricultural irrigation with wastewater has increased. In Mexico, about half of the wastewater is untreated and is discharged into bodies of water, soils and irrigation canals, the latter disposal site being the one that supplies six per cent of agricultural producers. The objective was to evaluate the quality of the plant material of the vegetable cactus Opuntia ficus-indica cultivar Atlixco with and without plant growth promoting bacteria, in plots irrigated with untreated wastewater from the Atoyac River, which contain potentially toxic elements in locations in the municipalities of Atlixco and Santa Isabel Cholula. The analysis of the potentially toxic elements in the plant material indicates that with the inoculation of Serratia K120, the concentration of Pb in the aerial part of the cactus decreased (5.76 ± 2.42 ppm) compared to the plants inoculated with Escherichia coli N16 (18.50 ± 2.42 ppm). Tukey (p ≤ 0.05). The results show that O. ficus-indica cultivar Atlixco inoculated with plant growth promoting bacteria is capable of phytostabilizing Pb by decreasing its bioavailability and mobility, which benefits human health and the environment.