Production of triploid Zantedeschia hybrids using embryo rescue

Abstract

Triploid hybrid plants were produced from crosses between diploid and tetraploid plants of the winter‐dormant section in the genus Zantedeschia. In five different crosses, the endosperm became degenerate and embryo development was restricted to the globular stage because of post‐fertilisation incompatibility. Using an embryo rescue technique, hybrid plants were produced from two crosses. These plants were confirmed to be triploids by counting chromosomes in root‐tip cells. The triploid plants flowered in a greenhouse and produced no pollen. As hybridisations among diploid plants in the winter‐dormant section are generally compatible, severe incompatibility in the diploid‐tetraploid crosses may be the result of the imbalance of chromosome numbers.

Keywords:

• calla lily
• triploid plants
• endosperm balance number
• post‐fertilisation incompatibility