International Journal of Research (IJR) Vol-1, Issue-10 November 2014 ISSN 2348-6848 ASSESSMENT OF IMPACT OF SIMULATED ACID RAIN ON THE GROWTH OF AMARANTHUS HYBRIDUS L. AND ABELMOSCHUS ESCULENTUS L. Okon, Okon Godwin and Akpan, Gabriel Ukpong Page | 985 Assessment of Impact of Simulated Acid Rain on the Growth of Amaranthus hybridus L. and Abelmoschus esculentus L. Okon, Okon Godwin* 1 and Akpan, Gabriel Ukpong 2 1 Department of Botany and Ecological Studies, University of Uyo, Nigeria. 2 Department of Crop Science, University of Uyo, Nigeria. *Corresponding author: okjunior4zeeb@gmail.com Abstract Assessment of the impact of simulated acid rain of different concentrations (pH 7.0, 6.0, 4.0 and 2.0) the growth and development of Amaranthus hybridus and Abelmoschus esculentus was carried out in the fieldusing earthen pots filled with 300 g sandy-loam soil. Seeds of A. hybridus and A. esculentus were planted in the different pots, after germination the plants were allowed to grow under normal conditions for one (1) week before applying the different grades of the simulated laboratory prepared acid rain every day for six (6) weeks. From this study, steady decrease in growth parameters of Amaranthus hybridus and Abelmoschus esculentus was observed with increasing acidity. Shoot length of A. esculentus recorded 109.20 ± 1.21 (control), 69.42 ± 1.01 (pH 6.0), 42.91 ± 0.34 (pH 4.0) and 24.86 ± 1.21 (pH 2.0) respectively. Similar observation was recorded for A. hybridus as its shoot length recording 69.21 ± 0.92 (control), 64.93 ± 0.41(pH 6.0), 54.21 ± 0.91 (pH 4.0) and 44.43 ± 0.28 (pH 2.0). Similar decrease was also recorded in the number of leaves, petiole length and leaf area. From this research, it is evident that acid rain can severely impede the growth and development of A. hybridus and A. esculentus. This could cause large scale loss to farmers and great economic loss to agricultural based economies. The occurrence of acid rain is likely to increase with steady and uncontrolled industrialization in the urban centres and spreading into the rural areas where these farmers grow these crops. Key Terms –Abelmoschus esculentus,Acid rain, Amaranthus hybridus,Nitrogen dioxide and Sulfur dioxide 1. Introduction Acid rain any form of precipitation or rain that is unusually acidic, meaning that it possesses elevated levels of hydrogen ions (low pH). It can have detrimental effects on plants, aquatic animals and infrastructure. Acid rain is caused by emissions of sulfur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids.The sources of atmospheric deposition can be categorized as either natural or anthropogenic (Bruno et al., 2006).Unlike the case of fluoride that is emitted by afewer industries such as the aluminum ones, thereare many anthropogenic sources that acidify rainwater. The acids come from cars and fossil fuel- burning electrical power plants. Sulfur dioxide (SO 2 ) and nitrogen dioxide (NO 2 )are the two main pollutants in the