Ruellia L. (Acanthaceae) consists of ≈300 species of perennial herbs, shrubs, small trees, and lianas with tropical, subtropical, or temperate distribution (Tripp, 2007). Ruellia simplex Wright (commonly known as Mexican petunia, Mexican bluebell, or Britton’s petunia) is a popular landscape plant in the southern United States because of its low maintenance requirements and prolific flowering (Gilman, 1999). It was introduced to Florida sometime before 1940 (Smith et al., 2016) and has naturalized in disturbed uplands and wetlands of seven southern U.S. states (from Florida and South Carolina, and west to Texas), plus the U.S. Virgin Islands, Puerto Rico, and Hawaii [United States Department of Agriculture (USDA), Natrual Resources Conservation Service, 2017]. The University of Florida Institute for Food and Agricultural Science (UF/IFAS) Assessment of the Status of Non-Native Plants in Florida’s Natural Areas (IFAS Invasive Plant Working Group, 2017) and the Florida Exotic Pest Plant Council (2017) consider R. simplex an invasive species and do not recommend its use in Florida.
In 2007, a Ruellia breeding program was initiated at UF/IFAS in Gainesville, FL, aiming to create new cultivars with highly reduced or no fertility for the landscape plant industry. To reduce the spread of R. simplex by seed, new cultivars are bred with reduced female fertility (no fruit or very low fruit production, or lack of seed viability) and reduced or lack of male fertility (Freyre et al., 2012a). MayanTM Purple (‘R10-102’, PP24422) and MayanTM White (‘R10-108’, PP25156) were released in 2012 (Freyre et al., 2012b), MayanTM Pink (‘R10-105-Q54’, PP26063) in 2013 (Freyre et al., 2014), and MayanTM Compact Purple (‘R12-2-1’, ppp) in 2016 (Freyre et al., 2016). These four cultivars were evaluated by the IFAS Assessment, and their landscape use in Florida was approved. R13-5-3, R15-24-17, and R16-1-1 were selected on the basis of their compact and full growth habit, thin leaves, semidwarf plant height, good performance and flowering, and no fruiting. R13-5-3 has purple flowers, R16-1-1 has red-purple flowers, and R15-24-17 has a new flower color for Ruellia, which is white corolla with red-purple throat.
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