New variety of paintbrush lily developed by a novel plant tissue culture technique

In plants, the number of chromosome sets in cells affects a large number of desirable characteristics. In general, the greater the number of chromosome sets, the more like the plant is to have larger flowers, larger fruits, be more disease resistant, and so on. In addition to increasing the ornamental value of this plant, this is one of the first studies that use «endosperm culture» — an application of PTC techniques — for non-cereal monocotyledonous plants. Their findings were published in the journal Plant Cell, Tissue and Organ Culture.

Triploid plants are quite unique among polyploid plants. This disadvantage can be overcome by generating hexaploid plants from triploid plants. Triploid plants are found naturally, albeit in very small numbers. They can be produced by cross-breeding diploid and tetraploid plants, or by PTC techniques.

albiflos, a food reserve tissue inside the seeds that is naturally triploid. The endosperm was grown into a mass of cells called a callus using a PTC technique. A portion of this tissue was then directly subjected to another PTC technique, organogenesis, to generate triploid plantlets of H. albiflos. Another portion of the callus was first treated with colchicine before organogenesis.

Yoichiro Hoshino is a Professor at the Field Science Center, Hokkaido University. He is interested in the utilization of plant genetic resources in the Hokkaido area and in developing novel breeding methods.