Pneumatode
In botany, pneumatodes are air-containing structures in plant roots.[1] Their function is to allow gaseous exchange in root tissues. This can be beneficial to semi-aquatic plants, such as neo-tropical palms.[2] Plants with photosynthetic roots, such as epiphytic orchids like Dendrophylax lindenii also possess these structures. They play a role in fungal interactions.[3]
Etymology
[edit]The name of the structure is derived from the Greek word πνεῦμα (pneûma), meaning breath and ὁδός (hodós), meaning pathway.[4]
Fungal interactions
[edit]Fungal infections of plants may begin through penetration of the roots through pneumatodes.[5]
Functional analogy to stomata
[edit]Pneumatodes are considered as a special type of cyclocytic stomata. The entire structure may rise above the adjacent epidermis. The pneumatodes may function as double structures for gas exchange and liquid water elimination (guttation).[6] Leafless orchids with photosynthetic roots rely on the gas exchange through pneumatodes for photosynthesis.
Taxonomic importance
[edit]These structures are characteristic for different species and can be used to differentiate between them. These features can be used to distinguish between palm species.[7] They can also be used in the field of paleobotany, as the structures may be preserved in fossilized roots.[8]
References
[edit]- ^ Rosa Belarbi-Halli, Jean Dexheimer, and François Mangenot. Le pneumatode chez Phoenix dactylifera L. I. Structure et ultrastructure. Canadian Journal of Botany. 61(5): 1367-1376. doi:10.1139/b83-146
- ^ J Balick, M. (1989). The Diversity Of Use Of Neotropical Palms.
- ^ Chomicki, G., Bidel, L. P., & Jay-Allemand, C. (2014). Exodermis structure controls fungal invasion in the leafless epiphytic orchid Dendrophylax lindenii (Lindl.) Benth. ex Rolfe. Flora-Morphology, Distribution, Functional Ecology of Plants, 209(2), 88-94.
- ^ Jaeger, Edmund Carroll (1959). A source-book of biological names and terms. Springfield, Illinois: Thomas. ISBN 0-398-06179-3.
- ^ Chinchilla, C. M. Fusarium Wilt (Fusarium oxysporum f. sp. elaeidis) In Oil Palm: A Rather Weak Pathogen?.
- ^ Rolleri, C., Deferrari, A. M., & del Carmen Lavalle, M. (1994). Epidermis y estomas porociclocíticos en Christensenia-cumingiana Crist (Marattiaceae-Marattiales-Eusporangiopsida). Revista del Museo de La Plata, 14(98), 207-218.
- ^ Balick, M. J. (1984). Ethnobotany of Palms in the Neotropics. Advances in Economic Botany, 1, 9–23. http://www.jstor.org/stable/43931365
- ^ Plaziat, J. C. (1995). Modern and fossil mangroves and mangals: their climatic and biogeographic variability. Geological Society, London, Special Publications, 83(1), 73-96.