ABSTRACT This experiment was carried out at Potrobangsan North Magelang District, Magelang City, since September until November 1988, at plastic House with regosol soil type, the average temperatur 26'c, at an elavation of 376 m. The purpose of this experiment was to study the influence of colchicine concentration on the growth and yield of onion (Allium cepa fa ascalonicum L)Â This …