II. 44. Chromosome number in progenies of selfed triploids.
J. Jensen, Agricultural Research Department, Atomic Energy Commission, Research Establishment, Risø, DK 4000 Roskilde, Denmark.*
*Visiting Associate Professor at Department of Agronomy, Colorado State University, Fort Collins, Colorado 80521, U.S.A. (1970-1971).
In plants grown from small seeds in the variety Bomi three triploid plants were found by J. Sandfaer, Riso, Denmark. These three plants were selfed and produced of 3, 9, and 17 kernels respectively. This seed was sown and the chromosome number from root tips of germinated kernels was counted with the following results (Table 1).
Table 1. Chromosome number observed in selfed progenies of triploid barley.
The chromosome numbers observed in the progenies of triploid Bomi are different from those found in previously investigated progenies of triploid barley. All plants in the progeny of triploid Bomi were aneuploids or triploid and no diploid plant was obtained. Also most of the plants had 2n=16 or higher chromosome number. The occurrence of plants with 25 chromosomes and 2 fragments and the plants with 27 chromosomes can be explained by transmission of more than seven chromosomes through the male gametes but the occurrence of the plant with 33 chromosomes is more difficult to explain. The plant with 33 chromosomes has been alive for more than five months, but the spike formation has not yet been observed, although the plant is quite vigorous.
