Dieffenbachia

Dieffenbachia /ˌdiːfɪnˈbækiə/[2] is a genus of tropical flowering plants in the family Araceae. It is native to the New World Tropics from Mexico and the West Indies south to Argentina. Some species are widely cultivated as ornamental plants, especially as houseplants, and have become naturalized on a few tropical islands.[1][3][4]

Dieffenbachia (dumb cane)
Dieffenbachia oerstedii at Chicago Botanic Garden
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Monocots
Order:	Alismatales
Family:	Araceae
Subfamily:	Aroideae
Tribe:	Dieffenbachieae
Genus:	Dieffenbachia Schott
Range of the genus Dieffenbachia.
Synonyms[1]
Seguinum Raf. Maguirea A.D.Hawkes

Dieffenbachia is a perennial herbaceous plant with straight stem, simple and alternate leaves containing white spots and flecks, making it attractive as indoor foliage. Species in this genus are popular as houseplants because of their tolerance of shade. Its English names, dumb cane and mother-in-law's tongue (also used for Sansevieria species) refer to the poisoning effect of raphides, which can cause temporary inability to speak.[5] Dieffenbachia was named by Heinrich Wilhelm Schott, director of the Botanical Gardens in Vienna, to honor his head gardener Joseph Dieffenbach (1796–1863).

Inflorescence of Dieffenbachia oerstedii

horizontal and vertical cross section of stem

Species

The World Checklist of Selected Plant Families lists the following species:[1]

1. Dieffenbachia aglaonematifolia Engl. – Brazil, Paraguay; Corrientes + Misiones Provinces of Argentina
2. Dieffenbachia antioquensis Linden ex Rafarin – Colombia
3. Dieffenbachia aurantiaca Engl – Costa Rica, Panama
4. Dieffenbachia beachiana Croat & Grayum – Costa Rica, Panama
5. Dieffenbachia bowmannii Carrière – Colombia, northwestern Brazil
6. Dieffenbachia brittonii Engl. – Colombia
7. Dieffenbachia burgeri Croat & Grayum – Costa Rica
8. Dieffenbachia cannifolia Engl. – Colombia, Ecuador, Peru
9. Dieffenbachia concinna Croat & Grayum – Costa Rica, Nicaragua
10. Dieffenbachia copensis Croat – Panama
11. Dieffenbachia cordata Engl. – Peru
12. Dieffenbachia costata Klotzsch ex Schott – Colombia, Ecuador, Peru
13. Dieffenbachia crebripistillata Croat – Panama
14. Dieffenbachia daguensis Engl. – Colombia, Ecuador
15. Dieffenbachia davidsei Croat & Grayum – Costa Rica
16. Dieffenbachia duidae (Steyerm.) G.S.Bunting – Venezuela, Guyana
17. Dieffenbachia elegans A.M.E.Jonker & Jonker – Bolivia, northwestern Brazil, the Guianas
18. Dieffenbachia enderi Engl. – Colombia
19. Dieffenbachia fortunensis Croat – Panama
20. Dieffenbachia fosteri Croat – Panama
21. Dieffenbachia fournieri N.E.Br. – Colombia
22. Dieffenbachia galdamesiae Croat – Panama
23. Dieffenbachia gracilis Huber – Peru, northwestern Brazil
24. Dieffenbachia grayumiana Croat – Costa Rica, Panama, Colombia
25. Dieffenbachia hammelii Croat & Grayum – Costa Rica, Nicaragua
26. Dieffenbachia herthae Diels – Ecuador
27. Dieffenbachia horichii Croat & Grayum – Costa Rica
28. Dieffenbachia humilis Poepp. – Bolivia, Peru, Ecuador, northwestern Brazil, the Guianas
29. Dieffenbachia imperialis Linden & André – Peru
30. Dieffenbachia isthmia Croat – Panama
31. Dieffenbachia killipii Croat – Panama
32. Dieffenbachia lancifolia Linden & André – Colombia
33. Dieffenbachia leopoldii W.Bull – Colombia
34. Dieffenbachia longispatha Engl. & K.Krause – Honduras, Nicaragua, Costa Rica, Panama, Colombia, Venezuela
35. Dieffenbachia lutheri Croat – Panama
36. Dieffenbachia macrophylla Poepp. – Peru
37. Dieffenbachia meleagris L.Linden & Rodigas – Ecuador
38. Dieffenbachia nitidipetiolata Croat & Grayum – Panama
39. Dieffenbachia obliqua Poepp. – Peru
40. Dieffenbachia obscurinervia Croat – Panama
41. Dieffenbachia oerstedii Schott – southern Mexico (Veracruz, Tabasco, Campeche, Oaxaca, Chiapas), Central America (all 7 countries), Colombia
42. Dieffenbachia olbia L.Linden & Rodigas – Peru
43. Dieffenbachia paludicola N.E.Br. ex Gleason – northwestern Brazil, the Guianas, Venezuela
44. Dieffenbachia panamensis Croat – Panama
45. Dieffenbachia parlatorei Linden & André – Colombia, Venezuela
46. Dieffenbachia parvifolia Engl. – northwestern Brazil, Bolivia, Ecuador, Peru, Venezuela
47. Dieffenbachia pittieri Engl. & K.Krause – Panama
48. Dieffenbachia seguine (Jacq.) Schott – West Indies, south to Brazil and Bolivia
49. Dieffenbachia shuttleworthiana Regel – Colombia
50. Dieffenbachia standleyi Croat – Honduras
51. Dieffenbachia tonduzii Croat & Grayum – Nicaragua, Costa Rica, Panama, Colombia, Ecuador
52. Dieffenbachia weberbaueri Engl. – Peru
53. Dieffenbachia weirii Berk. – Colombia
54. Dieffenbachia wendlandii Schott – southern Mexico (Querétaro, Veracruz, Oaxaca, Chiapas) south to Panama
55. Dieffenbachia williamsii Croat – Bolivia
56. Dieffenbachia wurdackii Croat – Peru

Dieffenbachia includes a number of unresolved taxonomic names, such as Dieffenbachia amoena.[6]

Ecology

In a survey which began in 1998, researchers in Costa Rica noticed that the strawberry poison frog Oophaga pumilio, deposited almost all (89%) of their tadpoles on the leaf axils of Dieffenbachia. As a result, the frog population fluctuated with the abundance of Dieffenbachia, especially in secondary forest. A majority of the plants were eradicated by 2012 when the surveyors returned to the same area, with only 28% of 2002 plant numbers remaining. Researchers concluded that the reason for the rapid decline in Dieffenbachia was due to increased abundance of the collared peccary Pecari tajacu in the La Selva Biological Station research area; a small pig-like animal which feeds on Dieffenbachia and other plants.[7]

Cultivation

With a minimum temperature of 5 °C (41 °F), dieffenbachia must be grown indoors in temperate areas. They need light, but filtered sunlight through a window is usually sufficient. They also need moderately moist soil, which should be regularly fertilized with a proprietary houseplant fertilizer. Leaves will periodically roll up and fall off to make way for new leaves. Yellowing of the leaves is generally a sign of problematic conditions, such as a nutrient deficiency in the soil. Dieffenbachia respond well to hot temperatures and dry climates.[8]

Dieffenbachia prefer medium sunlight, moderately dry soil and average home temperatures of 62–80 °F (17–27 °C). Most require water about twice a week.

As Dieffenbachia seguine comes from the tropical rain forest, it prefers to have moisture at its roots, as it grows all the time, it needs constant water, but with loose well aerated soils.[9]

The cultivars 'Camille'[10] and 'Tropic Snow'[11] have gained the Royal Horticultural Society's Award of Garden Merit.[12]

Toxicity

The cells of the Dieffenbachia plant contain needle-shaped calcium oxalate crystals called raphides. If a leaf is chewed, these crystals can cause a temporary burning sensation and erythema. In rare cases, edema of tissues exposed to the plant has been reported. Mastication and ingestion generally result in only mild symptoms.[13] With both children and pets, contact with dieffenbachia (typically from chewing) can cause a host of unpleasant symptoms, including intense numbing, oral irritation, excessive drooling, and localized swelling.[14] However, these effects are rarely life-threatening. In most cases, symptoms are mild, and can be successfully treated with analgesic agents,[15] antihistamines,[16] or medical charcoal.[17][18] Moreover, severe cases can occur if Dieffenbachia makes prolonged contact with oral mucosal tissue. In such cases, symptoms generally include severe pain which can last for several days to weeks. Hospitalization may be necessary if prolonged contact is made with the throat, in which severe swelling has the potential to affect breathing. Gastric evacuation or lavage is "seldom"[17] indicated. In patients with exposure to toxic plants, 70% are children younger than 5 years.

Stories that Dieffenbachia is a deadly poison are urban legends.[19]

• 
  A 47 year old 9.75 foot tall Dieffenbachia house plant
• 
  A large dieffenbachia with big bright green leaves on display as a houseplant
• 
  Dumbcane shoot
• 
  Dieffenbachia crossview

References

1. Kew World Checklist of Selected Plant Families
2. Sunset Western Garden Book. 1995. pp. 606–7. ISBN 978-0-376-03851-7.
3. Govaerts, R. & Frodin, D.G. (2002). World Checklist and Bibliography of Araceae (and Acoraceae): 1–560. The Board of Trustees of the Royal Botanic Gardens, Kew.
4. Croat, Thomas B. (December 2004). "Revision of Dieffenbachia (Araceae) of Mexico, Central America, and the West Indies". Annals of the Missouri Botanical Garden. 91 (4): 668–772. JSTOR 3298554.
5. "Dumb cane | plant". Encyclopedia Britannica.
6. "Dieffenbachia — The Plant List". www.theplantlist.org. Retrieved 2018-12-21.
7. McKone, Mark J.; Moore, Jonathan W.; Harbison, Christopher W.; Holmen, Ian C.; Lyons, Hillary C.; Nachbor, Kristine M.; Michalak, Julia L.; Neiman, Maurine; Nicol, Julia L.; Wheeler, George R. (2014). "Rapid collapse of a population of Dieffenbachia spp., plants used for tadpole-rearing by a poison-dart frog (Oophaga pumilio) in a Costa Rican rain forest". Journal of Tropical Ecology. 30 (06): 615–619. doi:10.1017/S0266467414000467. ISSN 0266-4674.
8. MacDonald, Elvin "The World Book of House Plants" Popular Books
9. "Dieffenbachia seguine". plantsrescue.com. Retrieved 18 December 2016.
10. "RHS Plantfinder – Dieffenbachia 'Camille'". Retrieved 12 February 2018.
11. "RHS Plantfinder – Dieffenbachia 'Tropic Snow'". Retrieved 12 February 2018.
12. "AGM Plants – Ornamental" (PDF). Royal Horticultural Society. July 2017. p. 16. Retrieved 24 January 2018.
13. Mrvos, Rita; Dean, Bonnie S.; Krenzelok, Edward P. (1991). "Philodendron/Dieffenbachia Ingestions: Are They a Problem?". Clinical Toxicology. 29 (4): 485–91. doi:10.3109/15563659109025745. PMID 1749055.
14. "Dieffenbachia". ASPCA.
15. Plant Poisoning, Caladium, Dieffenbachia, and Philodendron at eMedicine
16. GN Lucas – Sri Lanka Journal of Child Health, 2008 – "Plant poisoning in Sri Lankan children: A hospital based prospective study" (PDF). Archived from the original (PDF) on July 16, 2011. Retrieved March 17, 2009.
17. Lamminpää, Anne; Kinos, Marja (1996). "Plant poisonings in children". Human & Experimental Toxicology. 15 (3): 245–9. doi:10.1177/096032719601500310. PMID 8839213.
18. Šnajdauf, Jiří; Mixa, Vladimír; Rygl, Michal; Vyhnánek, Martin; Morávek, Jiří; Kabelka, Zdenĕk (2005). "Aortoesophageal fistula—an unusual complication of esophagitis caused by Dieffenbachia ingestion". Journal of Pediatric Surgery. 40 (6): e29–31. doi:10.1016/j.jpedsurg.2005.03.036. PMID 15991162.
19. "Common Household Plant Dieffenbachia Deadly Poisonous?". snopes.com. Retrieved 17 June 2017.

Sources

• Schott, H. W. and Kunst, W. Z. (1829). Für Liebhaber der Botanik.

External links

• Encyclopædia Britannica
• Clemson Home & Garden
• Medline Plus: Dieffenbachia
• Botanical Online: Dieffenbachia
• Speedup Video – Dieffenbachia growth