Somatic hybrids of Datura innoxia Mill.+Datura discolor Bernh. and of Datura innoxia Mill.+Datura stramonium L. var tatula L.

Summary Following fusion of protoplasts from a chlorophyll-deficient diploid mutant of Datura innoxia Mill. which can be regenerated to shoots, with green wild-type protoplasts of Datura stramonium L. var. tatula L. which can not, it was possible to isolate 49 green hybrid calli on agar medium. Most of these somatic hybrid calli gave rise to leaves and shoots. The chromosome numbers of the somatic hybrids were determined: 15 were tetraploid (amphidiploid), 24 hexaploid, and the other showed an aneuploid chromosome number.In a similar experiment protoplasts of the Datura innoxia mutant were fused with green wild-type protoplasts of Datura discolor Bernh. which are also not able to be regenerated, four green calli were obtained from which leaves and shoots developed after some transfers on agar medium. Three of them showed the amphidiploid (48) chromosome number, whereas one possessed an aneuploid number of 46 chromosomes.After transfer of rooted shoots to soil flowering plants could be obtained in both combinations. The habits of the somatic hybrids in both combinations were intermediate between the habits of the respective parental plants.Dedicated to my father, Prof. Dr. Theodor Schieder, on the occasion of his 70th birthday.