Summary Woody perennials including Populus spp. (poplars) have a juvenile phase that ranges from several years to decades in length. This and the year-long floral development process are major impediments to breeding and to fundamental research of reproductive traits. Here we report a CRISPR-empowered in vitro flowering system and demonstrate its application using three reproductive traits: sex, seed trichomes, and a previously undescribed potential for trimonoecy in poplar.

In vitrofloral development in poplar: Insights into seed trichome and trimonoecy regulation