IMPACT OF SPENT ENGINE OIL ON THE GROWTH AND DEVELOPMENT OF SWEET PEPPER (CAPSICUM ANNUM L.) IN KEFFI, NIGERIA

Abstract

This research investigates the impact of spent engine oil (SEO) on the growth and development of sweet pepper plants (Capsicum annuum L.) in Keffi, providing critical insights into the environmental risks associated with improper automotive waste disposal. The study includes a control group (C) and three experimental groups exposed to varying concentrations of spent engine oil (2%SEO, 4%SEO, and 6%SEO). While the initial germination phase showed no significant differences among treatments, a comprehensive analysis of subsequent growth parameters revealed substantial negative effects on plant height, girth, and leaf-related metrics. The control group displayed robust growth in all parameters, whereas experimental groups, particularly those exposed to higher SEO concentrations, exhibited a drastic reduction in these metrics, ultimately reaching a complete absence of measurable values by the study's conclusion. The findings align with previous research emphasizing the phytotoxic effects of spent engine oil, attributed to its complex composition containing heavy metals, polycyclic aromatic hydrocarbons, and other contaminants. The negative impact on plant height and girth suggests an inhibitory effect on critical growth processes, possibly disrupting cell elongation and expansion. The absence of measurable values in leaf-related parameters underscores the detrimental effects on foliar development, compromising the plant's ability to carry out essential physiological functions. This study contributes significantly to the understanding of spent engine oil's phytotoxicity and underscores the urgency of adopting sustainable waste management practices to mitigate its impact on agricultural ecosystems. The observed stunted growth and compromised physiological functions in sweet pepper plants highlight the need for further research to unveil the specific biochemical mechanisms underlying these effects, paving the way for targeted remediation strategies and sustainable agricultural practices in regions facing similar contamination challenges