Developmental flower transcriptomes of two recently evolved cleistogamous species and their sister chasmogamous species in the mycoheterotrophic genus Gastrodia

The diversification of plant reproductive systems has resulted in flowers that do not open at all for successful breeding by self-pollination. Such floral characters are called cleistogamy, which evolved in more than 30 angiosperm lineages. Although its highly repetitive evolution suggests that cleistogamy is a common evolutionary solution to withstand unfavorable conditions for cross-pollination, it has long been unclear how flower development has been modified to derive a common set of cleistogamous traits, such as reduced flower sizes. Here, we analyzed developmental flower transcriptomes of two recently evolved cleistogamous species and their sister chasmogamous species in the mycoheterotrophic genus Gastrodia.