Propagation Protocol for Jacquemontia Reclinata
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Beach jacquemontia (Jacquemontia reclinata House [Convolvulaceae]) is an endangered endemic plant from southeast Florida that can be propagated by seeds Jacquemontia Choisy is a tropical and or cuttings. Freshly harvested seeds from cultivated and wild plants can germinate subtropical American genus that easily in a greenhouse under South Florida ambient conditions. A higher germination belongs to the morning-glory family, success after short-term seed storage suggests an after-ripening effect; however, Convolvulaceae. There are 80 to 100 orthodox methods are acceptable for long-term storage. Soaking treatments do not species in this genus, and J. reclinata House, affect overall germination. Cuttings can produce new plants when treated with also known as beach cluster-vine or beach rooting hormone and planted in perlite. Arbuscular mycorrhizae fungi inoculation of jacquemontia, is closely related to 3 other cultivated plants is recommended for outplanting into habitats lacking natural threatened or endangered jacquemontias that fungal inoculum. These propagation techniques have yielded plants used for occur in southern Florida: J. curtisii Hallier, J. reintroduction and recovery activities of the species. havanensis (Jacq.) Urban, and J- pentanthos (Jacq.) G. Don. Jacquemontia reclinata can he Roncal J, Fisher J, Wright SJ, Frances A, Griffin K, Maschinski J, Fidelibus MW. 2006. distinguished from the other jacquemontias by Propagation protocol for Jacquemontia reclinato House, a federally endangered species of the presence of tiny hairs along the margins of South Florida. Native Plants Journal 7(3): 301-306. its outer sepals and by its rather broad succulent leaves (Austin 1979). KEY WORDS Jacquemontia reclinata (Figure I) is a coastal dune, coastal strand, Convolvulaceae, ex situ collection, soaked perennial vine with a stem branched at the seeds, storage behavior base and a stout taproot (Small 1934), although we have also observed 1.4 cm (0.56 in) diameter and < 2 m (6.6 ft) long roots NOMENCLATURE protruding in a radial direction and a USDA NRCS (2005) fibrous root mass (~15 x) Figure 1. Jacquemontia reclinata House (Convolvulaceae) blooming in Bill Baggs Cape Florida State Park, Florida. Photo by Samuel J Wright 301 NATIVEPLANTS I FALL 2006 10 cm [6 x 4 in]) close to the surface coupled with stochastic events, or salt water (see germination sidebar). (Figure 2). Branches are slender and seriously threaten J. reclinata's Germination of seeds is easily elongate, widely radiating, woody at the persistence. These factors led to listing attained on commercially available base, and may twine over other plants J. reclinata as federally endangered soilless media (for example, Metromix (Small 1934; Robertson 1971). in 1993. 360, VJ Growers Supply, Apopka, The leaves are entire, spirally arranged, Fairchild Tropical Botanic Garden Florida) or Fairchild's standard potting more or less succulent, and finely has developed propagation methods mix (10% perlite, 40% Canadian peat, pubescent, at least when young (Small to aid in conservation and recovery 20% composted bark, and 30% sand). In 1934). Jacquemontia reclinata's white efforts of J. reclinata. Knowledge of pots, soil is gently tapped down to to light-pink flowers may be germination and propagation create a flat surface and then watered. present from November to May protocols is required to produce After the excess water drains, (Robertson 1971) or year-round (Austin plants for reintroduction and nonsoaked seeds are sown and and others 1991). Twenty-two species augmentation, as well as to establish top-dressed with about 1 cm (0.4 in) of of insects—mostly small bees and bee and maintain ex situ populations of chicken grit or sand. The top-dressing flies, and less frequently wasps, living plants and seeds. Here we grit reduces compaction from butterflies, and ants—are known to visit present our standard propagation con- watering, reduces moss and weed the flowers and may pollinate them ditions for J. reclinata based on the growth, and prevents seeds from (Pinto-Torres 2004). Few seedlings or results of seed and vegetative washing out of the pot (Carrara 2005). young plants are found near adults in propagation experiments. Adding pea-sized rock (The Bushel Stop, the wild. Although rarely observed, Lake Worth, Florida) to the medium in a seedlings are typically found in the 1:1 ratio (v:v) increases aeration and shade of adjacent shrubs and trees, SEED PROPAGATION drainage and reduces plant mortality and they send lateral stems from their by the root rot pathogen Fusarium rootstocks into more exposed areas Jacquemontia reclinata fruits suitable for solari. To minimize plant roots when maturity is reached. propagation are light brown-colored intertwining and then being disturbed Currently, there are 10 known popu- capsules about 4 to 5 mm (0.16 in) long, during transplanting, we prefer pots over lations of J. reclinata, which range in generally with 4 seeds (2.5 to 3 mm flats and transplant seedlings before size from 1 to 245 plants. These [0.11 in] long) per capsule (Robertson they are 9 wk of age. populations are within a 145-km (90-mi) 1971), which are shed throughout the Once sown, pots are placed on a stretch of coastline in southeast Florida, flowering season. Our experience is that greenhouse bench that receives 30% between Dade and Palm Beach there are 343 seeds per gram. sun under South Florida ambient counties (Wunderlin 1998; USFWS From our work, we have discovered conditions (25 °C to 35 °C [77 °F to 95 1999; Coile 2000). Within its range, J. several things about J. reclinata seeds °F], 54% to 87% relative humidity, –11 reclinata is found on disturbed or open that help us achieve more successful to 12 hours photoperiod) and watered sunny areas of coastal sand dunes, germination. First, we must ascertain 3 times per wk. Seeds germinate mostly on the crest and lee side seed source because different readily under these greenhouse (Austin 1979), and on open areas of germination behavior and requirements conditions, indicating the lack of maritime hammocks (Robertson 1971) and storage effects have been identified primary dormancy in this species. from 1 to 9 m (3.3 to 29.7 ft) above sea between cultivated and wild seedlots Jacquemontia reclinata seeds do level (Maschinski and others 2003). It (see sidebars), as is the case with other not require light to germinate; however, may also invade and restabilize the species (Rojas-Arechiga and others we recommend the use of light above habitats after a tropical storm, 2001; Singh and l)eswal 2002). Second, because seeds exposed to light have hurricane, or tire disturbance (USFWS seeds from cultivated and wild plants more uniform germination. We found 1999). can be stored successfully under a that 1-y-old seeds placed on filter paper The primary habitat of this species variety of conditions, and short-term in Petri dishes, exposed to 30% sunlight has been destroyed by commercial and storage can actually increase or kept dark by wrapping the dish with residential development, including park- germination (see storage sidebar). Our aluminum foil, and placed under ing lots and picnic areas, and by beach preferred storage technique for seeds greenhouse conditions described above, erosion (USFWS 1999). In some from cultivated plants is 3 mo at 12 °C yielded the same germination (40%) locations, J. reclinata is negatively (54 °F) and from wild plants is 1 mo at after 15 d. affected by competition with native and ambient conditions (23 °C [73 °F] and nonnative species (USFWS 1999). 60% to 84% relativehumidity). For a About 700 individuals remain in the longer storage time (for example, 42 wild, most of which (79%) occur in 3 mo), we recommend using a –20 °C (-4 302 populations(Maschinski and others °F) freezer. Third, the yellow pigment 2005). The small geographical range, released from seeds during soaking habitat fragmentation, low recruitment does not appear to affect germination, rate, and small population sizes nor does soaking seeds in fresh water NATIVEPLANTS I FALL 2006 PROPAGATION PROTOCOL FOR JACQUEMONTIA RECLINATA VEGETATIVE PROPAGATION MYCORRHIZAL ACKNOWLEDGMENTS REQUIREMENT Seeds may not always be available This research was funded by the Florida because of seasonality. Also, because of Wild J. reclinata plants have typical Department of Agriculture and Con- changing environmental factors (for Arum-type arbuscular mycorrhizal fungi sumer Services, the US Fish and example, canopy closure), existing J. (AMF) in their roots. AMF significantly Wildlife Service, and by the Institute of reclinata habitat may not have suitable increase the dry weight and total phos- Library and Museum Services. The conditions for flowering and seed phorus content of seedlings grown on authors, all of whom worked at production. Because of these factors, native soil under greenhouse conditions Fairchild Tropical Botanic Garden genetic preservation of declining (Fisher and Jayachandran 2002). when research was conducted, are populations may be possible only Jacquemontia reclinata is not an grateful to Jennifer Possley, Kristie through clonal propagation. obligate mycotroph because additions Wendelberger, Sonya Thompson, Therefore, it is critical to develop of phosphate without AMF also Lauren Linares, Ken Neugent, Randy vegetative propagation methods. promoted seedling growth (Fisher and Ploetz, Christopher Kernan, The Florida Immediately after removing cuttings Jayachandran 2002). Therefore, for our Native Plant Society, Miami Dade College from the donor plant, which can be done experiments, we do not add AMF to our students, and Miami-Dade Natural Areas at any time of the day, we dip them first in pots. AMF inoculation of cultivated Management for their help in different tap water and then in Rootone® plants, however, would be desirable for stages of this work. Susan Carrara and (GardenTech, Lexington, Kent ucky), wrap outplanting into habitats free of natural Dena Garvue contributed to the seed stor- them in a wet paper towel, enclose them AMF inoculum, such as coastal dredge age experiments.