Abstract
The writer studied the meiosis of three species hybrids in Nicotiana under the guidance of Dr. Y. TAKENAKA. The investigated hybrids were N. alata X N. Langsdorffii and the reciprocal, N. tabaculec X N. Lalegsdorffii and N. rustica X N. Lalegsdorffii. The external appearance of the hybrid N. alata (n =9) X N. Langsdorffii(n =9)corresponds well with descriptions given by other investigators. In about 78% of PMC's the chromosomes conjugated at MI as a rule to form 9 bivalents. Another chromosome configuration often observed was 7II+1IV (13%). Other configurations, such as 7II+1III+1I, 8II+2I, 6n+1IV+2I, 5II+2IV or 6II+2III, were also observed, each in less than 4% of PMC's.At AI one or two chromosome bridges were observed. The pollen produced appeared fairly normal and abundant seeds were obtained.
