Genomes of Wild Parents Reveal Complex History of Garden Petunias

An international team of researchers has sequenced the two wild parent species of the domesticated petunia. The study reveals petunia's complicated genetic history, having undergone one whole genome triplication shared with all the Solanaceae, and identifies an especially dynamic portion of the genome containing genes for color and scent.

Aside from its horticultural use, petunia is also utilized to study transposable elements and serves as a model system to study flower development, scent production, and interactions with pollinators.

Domesticated petunias (Petunia hybrida) are a hybrid of two wild species: one with a small, purple flower called Petunia inflata and one with a larger white flower called Petunia axillaris. Through intense breeding over the last 200 years, people have created petunia varieties that flower in almost any color of the rainbow.

The researchers expected that the garden petunia would have received about half of its genes from each parent, but they saw that the hybrid plant's genome was about 80 percent white petunia and only about 10 percent purple petunia. The remaining 10 percent of the genes were a mosaic—bits and pieces of sequences from each parent mixed together.

For more details, read the news release at the Boyce Thompson Institute website.