ABSTRACT

Effect of cement dust on photosynthetic pigments and leaf area of Mangifera indica and Anacardium occidentale was carried out. Sampling was carried out at two locations - Dangote Cement Factory, Obajana and Fourth Republic Housing Estate, Lokoja, Kogi State. The leaves of the two species were collected from these two areas with potentially higher and lower levels of air pollutant. Chlorophyll a, chlorophyll b and total chlorophyll concentration as well as leaf area were quantified and measured by digesting 100 mg of leaf sample with DMSO and light absorption at 663 nm and 645 nm were read using a 721G UV- VIS spectrophotometer. There were decrease in the chlorophyll a concentration (8.36 %, 16.26 %), chlorophyll b (35.38 %, 28.50 %) and total chlorophyll concentration (22.34 %, 14.90 %) of M. indica and A. occidentale respectively. Duncan MR, SNK and Turkey HSD one way ANOVA showed no significant reduction (P < 0.05) in chlorophyll a of M. indica leaves at the two study sites. Whereas, reduction in chlorophyll b and total chlorophyll concentration of M. indica and chlorophyll a and b as well as total chlorophyll concentration of A. occidentale were significantly different from each other (P < 0.05). The chlorophyll concentration of the research plants species thatwere far away from the cement industry were noted to be higher than those near the industry. The mean leaf area of M. indica in the polluted and non-polluted sites were 81.66 ± 3.56 cm² and 73.61 ± 3.91 cm² respectively. Whereas, the mean leaf area of A. occidentale in the polluted and non-polluted site were 66.54 ± 3.02 cm² and 63.07 ± 3.01 cm² respectively. Nevertheless, there was no significant difference in the mean leaf area of M. indica and A. occidentale at 0.05 % significance level.