The Effects of azadrachtin on mitotic division in root tip meristem cells of Allium cepa L.

36 SUMMARY Azadirachtin, which is used as a biopesticide obtained from Melia azedarach. Melia azedarach belongs to the Meliaceae family and grown in the parks and gardens of our country. Genotoxic effects of Azadirachtin have been investigated with a plant test system. The kernels were obtained from the fruits of Melia azedarach species in Aydın. The effects of the extracts at 25 gr kernel/It, 50 gr kernel/It and 75 gr kernel/It have been investigated with Allium test, which is a plant test system. The roots that were obtained, have been used in microscopic observations. Azadirachtin was found to be effective on cell division and chromosomes with respect to control group. But at the 50 gr kernel per It. concentration, which is recommended in the agricultural application, Azadirachtin showed the lowest effect. As a result of the countings, it was found that Azadirachtin decreases the mitotic indexs. It was thought that the harmful effects of Azadirachtin would be low and Azadirachtin would decrease the use of traditional chemical pestisides.