Mutants tolerant to low-temperature conditions induced in suspension culture as a source for improvement of Euphorbia pulcherrima Willd. ex Klotzsch

Under the pressure of the present oil crisis greenhouse cultivation of Euphorbia pulcherrima at a temperature optimum of about 200C is energy consuming and therefore very expensive. Horticulturalists are searching for plant types tolerant to temperatures below the optimal one applied at present. The aim of current experiments is to produce low-temperature-tolerant ideotypes by mutation induction in suspension culture. X-irradiation of cells, cell groups or small calli parts and screening under temperature stress conditions resulted in an increased number of dividing cells, measured by a larger calli size and an increased number of developing plants compared with the non-irradiated control. (author)