White campion (Silene latifolia, Caryophyllaceae) is a classical model species for studies of sex determination and chromosome evolution in dioecious plants. Deletion mapping this revealed the presence two Y-linked determining genes—the stamen promoting factor (SPF) gene gynoecium suppressing (GSF), which inspired development classic ‘two genes’ dioecy evolution. We recently identified GSFY tha...

Summary Clusia falcata (Clusiaceae), a new species from Chiapas, Mexico, is described and illustrated. This taxon distinctive for its leaves, among the narrowest of all known species, having lanceolate to oblong laminas that are mostly 10 – 15 × 2 2.5 cm. The flowers have quadrangular perianth with succulent petals, non-resiniferous androecium gynoecium. Staminate androphore bearing 18 24 short...

Many hemiparasites, including several members of the Castilleja genus (Scrophulariaceae), obtain secondary compounds from their host plants. Both Castilleja miniata in subalpine Colorado and C. indivisa in central Texas have reduced herbivory when obtaining alkaloids from the hosts Lupinus argenteus and L. texensis (Fabaceae), respectively. However, pollinators were not deterred from visiting C...

Organ formation relies upon precise patterns of gene expression that are under tight spatial and temporal regulation. Transcription patterns are specified by several cellular processes during development, including chromatin remodeling, but little is known about how chromatin-remodeling factors contribute to plant organogenesis. We demonstrate that the trithorax group (trxG) gene ULTRAPETALA1 (...

The plant specific transcription factor LEAFY (LFY) plays a pivotal role in the developmental switch to floral meristem identity in Arabidopsis. Our recent study revealed that LFY additionally acts downstream of AUXIN RESPONSE FACTOR5/MONOPTEROS to promote flower primordium initiation. LFY also promotes initiation of the floral organ and floral organ identity. To further investigate the interpl...