Journal of Threatened Taxa |
www.threatenedtaxa.org | 26 July 2021 | 13(8): 19189–19190
ISSN 0974-7907 (Online) | ISSN 0974-7893
(Print)
https://doi.org/10.11609/jott.6218.13.8.19189-19190
#6218 | Received 24 May 2020 | Final received
07 July 2021 | Finally accepted 09 July 2021
Occurrence of vivipary
in Ophiorrhiza rugosa Wall. (Rubiaceae)
Birina Bhuyan
1 & Sanjib Baruah 2
1,2 Department of Botany, Bodoland
University, Kokrajhar, Assam 783370, India.
1 birinabhuyan305@gmail.com, 2
sanjibbaruah9@gmail.com (corresponding author)
Editor: V. Sampath Kumar, Botanical
Survey of India, Coimbatore, India. Date of
publication: 26 July 2021 (online & print)
Citation: Bhuyan,
B. & S. Baruah (2021). Occurrence of vivipary
in Ophiorrhiza rugosa Wall. (Rubiaceae). Journal of Threatened Taxa 13(8): 19189–19190. https://doi.org/10.11609/jott.6218.13.8.19189-19190
Copyright: © Bhuyan
& S. Baruah 2021. Creative Commons Attribution
4.0 International License. JoTT allows unrestricted use, reproduction, and
distribution of this article in any medium by providing adequate credit to the
author(s) and the source of publication.
Funding: Self -funded.
Competing interests: The authors
declare no competing interests.
Acknowledgements: The authors gratefully
acknowledge the Assam State Biodiversity Board for granting permission to
explore the study area. The first author is indebted to Selim Mehmud, Department of Botany, Cotton University and Kensing Tisso, Karbi Anglong, Assam for their
support during the field visit.
Ophiorrhiza rugosa Wall. (Family Rubiaceae),
a highly valuable medicinal herb and a potential source of Campothecin
(CPT) used as an anticancer alkaloid producing plant (Gharpure
et al. 2010). There are many natural varieties of O. rugosa Wall., which
are now considered as strong candidates for the CPT (Hsiang et al. 1985; Vineesh et al. 2007).
Vivipary is the process-by which seeds
germinate within the fruits followed by embryo development before the seeds are
dispersed from the parent plant. Vivipary has been
considered as a precocious germination, relatively unusual phenomenon in
angiosperms (Farnsworth 2000).
Here, we report an unusual
occurrence of the viviparous germination of seeds of Ophiorrhiza
rugosa in the wild. This rare
phenomenon was observed during the field visit to Karbi
Anglong District, Assam in the last week of May 2019.
The sites were located in 25.9540N and 92.6030E, at 128m.
The rainy season in this area is with 90% of the rainfall during April–June
(60–70 days). On an average, the area receives 1,400–2,000 mm of rainfall; and
the soil is clayey loam.
The authors observed an
occurrence of the true viviparous germination in the plant growing on hill
slopes (Image 1). The plant is fully grown and contains the mature capsules. The capsules of the plant contain two halves
and the seedlings were growing within the halves. The germination of seeds was
epigeal and one capsule contains an average of 4–5 seedlings (Image 2D). Of the total seeds in a capsule, 75% showed
viviparous germination. The species which show viviparous germination were collected
during a period of almost continuous rainfall in the region. The location of
plant was along the sloppy mountain where splash water could easily accommodate
the capsule which might be triggered the germination inside the capsule. We
presume that due to continuous precipitation and splashing of water from the
stream resulting in inducing vivipary in the species.
It has been suggested that vivipary is a specialized
feature of evolutionary and biological importance that ensures survival of
plant (Cota-Sanchez 2004). The results may be useful in large-scale propagation
to meet increasing CPT demand and conservation of this valuable medicinal herb.
References
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