Pinguicula (Lentibulariaceae) is a genus of more than 100 carnivorous plant species. A handful of comprehensive studies have examined the reproductive ecology of these species, mostly in Europe and none in the USA. During 2013–2016 different aspects of the reproductive ecology of P. ionantha, P. lutea and P. planifolia were studied at multiple locations in the Florida Panhandle, USA. All three species are of conservation concern within the study region and some aspects of their reproductive ecology may be contributing to their rarity. For all species, we conducted breeding system studies investigating xenogamy vs. autogamy, self‐incompatibility vs. self‐compatibility, pollen:ovule ratios, flower phenology and longevity, and pollinator visitation, as well as fruit and seed set differences among populations. All three Pinguicula species were determined to be xenogamous and self‐compatible, although the pollen:ovule ratios were extremely low. In addition, these species have floral nastic movements and flower longevity that ranges from 2 to 3 weeks depending on the species. Hymenoptera was identified as the primary group of pollinators visiting all species, although observed visitation events were low. All three Pinguicula species had extremely high levels of fruit set and seed set. Worldwide, Pinguicula species share similar breeding system and reproductive patterns. The rare status of P. ionantha, P. lutea and P. planifolia is more likely due to their ecological requirements, demographics and/or patterns of genetic diversity, than reproduction. This work is among the first and most comprehensive associated with the reproductive ecology of North American Pinguicula.

Penstemon tubaeflorus is a North American prairie forb of conservation concern.Protocols for seed germination and transplant production involving fertilization are needed for conservation purposes. Our objectives were to compare techniques for breaking seed dormancy and increasing germination, and to investigate fertilizer on growth of Penstemon tubaeflorus. Seed treatments were hickory smoke seasoning solution (1:10, 1:100, 1:500, and 1:1,000), light vs. dark, prairie plant ash solution (2, 4, 8, and 16 g/L), and cold moist stratification (1 or 2 mo at 4°C). Seeds were germinated in Petri dishes in germination chambers and counted for 21 d. For hickory solutions, 1:100 had the highest germination (51%), and seeds germinated in light, but not in the dark. For ash solutions, 8 g/L (6%) and control (4%) germinations were higher than 2 g/L with 4 g/L and 16 g/L being intermediate. Germination increased for both stratification durations (37%) compared to control (2%). For fertilizer studies, seeds were planted in soilless mix with no fertilizer, liquid fertilizer (20-20-20 at 1.25 g/L water), or solid fertilizer (14-14-14 slow release at 14.6 g/L mix) in growth chambers. After 7 wk, shoot fresh mass, leaf number, leaf area, crown diameter, root length, and shoot dry mass were measured. Seedling growth was greatest with solid fertilizer compared to control and liquid fertilizer, which were similar. Overall, hickory solution at 1:100 with light produced the highest percent germination among all treatments, and solid fertilizer was most effective for transplant development. These findings are useful for management or restoration of P. tubaeflorus populations.

Anthocyanins in the leaves of carnivorous plants are suggested to play a role in prey capture. In this study, we investigated the role of red leaf coloration (an indicator of anthocyanins) on prey capture using Pinguicula planifolia (Chapman's Butterwort). Overall, red leaves had less prey (i.e., Collembola) than green leaves, suggesting that red coloration does not enhance prey capture for Chapman's Butterwort. However, the frequent presence of Collembola on leaves suggests that this plant species could be relying on other cues to attract prey (e.g., olfactory cues).

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