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Verma, Susheel
- Loss of Forest Tree Species:A Threat to Epiphytic Lichen Diversity of Jammu and Kashmir
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Affiliations
1 Centre for Biodiversity Studies, School of Biosciences and Biotechnology, BGSB University, Rajouri-185 234, Jammu and Kashmir, IN
2 National Botanical Research Institute, Rana Partap Marg, Lucknow (UP)-2260001, IN
1 Centre for Biodiversity Studies, School of Biosciences and Biotechnology, BGSB University, Rajouri-185 234, Jammu and Kashmir, IN
2 National Botanical Research Institute, Rana Partap Marg, Lucknow (UP)-2260001, IN
Source
Journal of Environment and Sociobiology, Vol 14, No Spl (2017), Pagination: 15-15Abstract
The present study was conducted for documenting the epiphytic lichen diversity in PirPanjal mountain ranges of Inner Himalaya of Jammu and Kashmir State of India. A total of 21 species of epiphytic lichens growing over numerous tree species were collected, identified and documented from the study area. It was further observed that Quercusleuco trichophora appeared to be the most favoured tree species for the epiphytic lichens as nine out of the 21 species were found to be growing on it. Many factors during the course of present study have been identified which have badly impacted the growth of epiphytic lichens in the region. Many of the tree species which form an ideal habitat for these lichens are being exploited for one or the other reason. The loss of tree species, therefore, will lead to the vanishing of many important lichen species from the area. It will ultimately lead to loss of biodiversity in general and epiphytic lichens in particular.
- Floral Biology and Embryological Studies are Important for Conservation of Threatened Plants Having Reproductive Bottlenecks:A Case Study of Illicium griffithii Hook. f. & Thomson
Abstract Views :338 |
PDF Views:102
Authors
E. J. Marbaniang
1,
N. Venugopal
1,
Susheel Verma
2,
Ravinder Raina
3,
Ankush Khajuria
2,
Kamini Gautam
3
Affiliations
1 Department of Botany, Centre of Advanced Studies in Botany, North Eastern Hill University, Shillong 793 022, IN
2 Centre for Biodiversity Studies, Baba Ghulam Shah Badshah University, Rajouri 185 234, IN
3 Department of Forest Products, Dr Y.S. Parmar University of Horticulture and Forestry, Solan 173 23, IN
1 Department of Botany, Centre of Advanced Studies in Botany, North Eastern Hill University, Shillong 793 022, IN
2 Centre for Biodiversity Studies, Baba Ghulam Shah Badshah University, Rajouri 185 234, IN
3 Department of Forest Products, Dr Y.S. Parmar University of Horticulture and Forestry, Solan 173 23, IN
Source
Current Science, Vol 114, No 03 (2018), Pagination: 576-587Abstract
Information on reproductive biology of threatened plant species could be useful for conservation, particularly when the species fails to perpetuate in nature due to regeneration failure. In flowering plants, the domain of reproductive biology includes structural details of reproductive units such as flower or inflorescence, formation of viable gametes, pollination dynamics, role of pollinators, pollen–pistil interactions as determined through compatibility, breeding system and mating strategies, fertilization and embryogeny, seed development, dispersal and germination. The importance of reproductive biology in species conservation has been demonstrated through a case study of Illicium griffithii Hook f. & Thomson, a threatened plant species from Arunachal Pradesh. I. griffithii (Illiciaceae) is a member of the ANITA clade and a representative taxon of the three most basal angiosperms. The flowers of I. griffithii are obligate xenogamous, and hence compatible pollen grains only germinate on the stigmatic papillae. Esterase and phosphatase enzymatic activities are absent in most stigmatic surfaces. Therefore, stigmatic receptivity is absent in many carpels. The ovules are anatropous and bitegmic with a four-celled/four-nucleate structure of embryo sac at maturity. Antipodals and filiform apparatus are absent. Presence of mucilage cells in the embryo sac facilitates the entry of pollen tubes into it. Embryolike organization of the endosperm is present, with one pole globular having smaller cells and the other pole roughly filamentous with larger cells resembling that of a suspensor. Extragynoecial compitum is not observed in I. griffithii. The flowers are brooding sites for the midges and the young ovules are eaten by larvae of the midges. Only 10% of the flowers mature into 13-seeded fruits and the carpels of the remaining 90% of the flowers have seeds ranging from 1 to 5. The seedling survival rate is only 7%. In addition to the above-mentioned reproductive bottlenecks, the species is also being over-harvested. It is now categorized as endangered. The findings of the present study on reproductive biology of I. griffithii should help in improving its conservation status.Keywords
Embryological Studies, Floral Biology, Illicium griffithii, Reproductive Bottlenecks, Threatened Species Conservation.Full Text
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