Triploid property of senno (Lychnis senno Siebold et Zucc., Caryophyllaceae), a traditional ornamental plant conserved in Japan

Abstract

'Senno' (Lychnis senno Siebold et Zucc., Caryophyllaceae), is a traditional and endangered ornamental plant species and presently only eleven strains have been confirmed to be under cultivation in nine localities in Chugoku and Kyushu districts of Japan. Analyses on chromosome number and nuclear DNA contents using flow cytometry revealed that all of the strains are triploid (2n = 36). The average of meiotic chromosome configuration (10.1III + 1.9II + 1.9I) observed in one strain indicated that 'Senno' is an autotriploid. Chromosome bridges, lagging chromosomes and micronuclei were observed in microsporogenesis. Although about 70% of pollen showed stainability with cotton blue solution, 'Senno' plants conserved in Japan did not produce any viable seeds by self-pollination. The origin of the 'Senno' conserved in Japan is discussed.