Effects of leaves and fruits of Melia azedarach L. (Meliaceae) from Eastern Mediterranean on soil carbon mineralization

Present study was carried on soils of three Melia azedarach L. (Neem tree) growing in Çukurova University Campus under the influence of Mediterranean climate. Carbon mineralization was investigated by respiration method in control soil, and in soils added with the same and double amounts of carbon containing fruits and leaves of the plant separately. Mineralization was also observed in azadirachtin, a natural insecticide, added soil.Carbon mineralization decreased in soils mixed with the leaf and fruit in the first 3 days and then increased in all samples and its rate was 0.92 % in control group and 0.76 % in soil mixed with azadirachtin (150 mg/100 g soil). Whereas mineralization rates were 1.71 % and 1.01 % in soils added single and double amounts of carbon containing leaf added and were 1.77 % and 0.96 % in soils added with the same amounts of carbon containing fruit added soils respectively.Carbon mineralization was insignificant at all groups in the first three days, which showed a considerable increase in fruit and leave added groups on the following days. Although there was no difference in carbon mineralization between the control and azadirachtin added soils, and between the fruit and leave added soils, carbon mineralization decreased significantly in the latter two soils (P<0.001).