Biochemical interaction between Eucalyptus, Neem residues with some plants and microorganisms

The study was carried to determinate the allelopathic effects of Eucalyptus globules and Azadirachta indica against Raphanus sativus and Lepidium sativum by adding their residues to the soil at rates of (3 , 6) gr / kg soil . The second part of study was to extract the oil seed and determine the biological activities against some pathogenic microorganisms namely Escherichia col, Klebesiella pneumonia, Staphylococcus aureus, Pseudomonas aeruginosa, Proteus mirabilis. These oils used at cons. (2.5, 5, 10, 15)% prepared and separated by stem distillation. Agar well diffusion method was used in bacteria preparing, and comparing extracts effect by determining the inhibition zone. Residues of Eucalyptus and Neem added to the soil at rates of 3gr/ kg soil significantly reduced the seed germination number and shoot length. While adding 6gr/ kg soil inhibited the seedling growth. Also the result shows inhibitory effects of the Eucalyptus oils against E .coli, S. aurus and K. pnenumonia, put there was no inhibition against P. aeruginosa and P.mirablils treatments. In conclusion, it seem much useful to cultivated Eucalyptus and Neem trees at river bank and lake beach because their residues could be use as herbicides, antibacterial against same microorganisms which polluted the water.