Influence of a Mixture of Spent Engine Oil, Fresh Diesel and Gasoline on Nerica Rice (Tox, Mecux and Wita.4) Tiller and Panicle Parameters

Abstract

Rice provides a staple food for more than half of the world’s population. Therefore, in order to improve rice production, it is imperative to elucidate how rice physiological parameters will respond to anticipated unfavorable changes in soil as a result of petroleum products contamination. The results of this work showed that leaf elongation rate was unaffected most especially in Tox variety compared with the control plants (P > 0.05). Whereas, progressive decrease in leaf area index and shoot growth dynamics of the three varieties (P<0.05, P < 0.01 and P < 0.001) were recorded for plants seeded in 2–5% pollutants mixture. Statistical analysis shows that no significant reduction was observed in main–culm leaf number of the three NERICA rice varieties (P > 0.05).Although, the number of tillers and number of productive tillers produced by the plants were reduced at 3–5% treated soils (P < 0.05, P < 0.01 and P < 0.001), except Tox variety (P > 0.05).The results indicated that percentage tillering efficiency of the three NERICA rice varieties was unaffected by the pollutant (P > 0.05). However, 2–5% concentrations of the pollutant mixtures significantly reduced the rate of panicle extrusion and panicle weight (P < 0.05, P < 0.01 and P < 0.001), while panicle length and panicle number were unaffected (P > 0.05). The results of this study suggest that knowledge of stress and disturbance physiology can contribute to rice production programmes in oil polluted environments.