Effect of waste water treatment on the growth of selected leafy vegetable plants

Abstract

Quetta, the capital city of Baluchistan province which was once called as “little London” has been affected by severe drought since 1998. This situation led to fresh water shortage which compelled the local population to irrigate their crops by waste water. In this way, heavy metals started to accumulate in the soil and as well as in our food chain. The main objectives of this research were to elucidate the effect of waste water on leafy vegetables growth. For this purpose, three leafy vegetables were selected i.e. Coriander (Coriandrum sativum), Purslane (Portulaca oleracea) and Lettuce (Lectuca sativa). The research is also aimed to know the influence of waste water treated plants on human health. The experiments were performed in the botanical garden, Botany Department, University of Baluchistan. Waste water was collected from waste water channels of the Quetta city. From March 2016-14 June, 2016, after an extensive survey, different sites of the municipal were selected for the collection of waste water used as sample collected from the Agriculture Department of Quetta city. Vegetative growth parameters such as height, number of leaves, weight of fresh, dry leaves and rate of germination of seed were measured to know the impact of waste water treatment. Waste water treatment had found a significant effect on the growth of leafy plants. All the growth parameters were measured in the three selected leafy vegetable plant species i.e. Coriander (Corianderum sativum), Purslane (Portulaca oleracae) and Lactuca (Lactuca sativa). Comparatively, better results were found by treating the plant with waste water rather than fresh water. The usage of municipal wastewater for irrigation can be an abundant resource of the nutrients essential for plant’s growth. However, keeping in view the health hazards, edible crops irrigated with this untreated waste water should not be grown in spite of its positive impact on the physical parameters of some plants.