Informatics Publishing Limited

G. Ravikanth , R. Vasudeva , R. Uma Shaanker , K. N. Ganeshaiah

Abstract

No abstract

Full Text

     

Singh Shweta ¹, B. R. Gurumurthy ², M. M. Vasanthakumari ¹, G. Ravikanth ³, S. Dayanandan ⁴, R. Storms ⁴, M. B. Shivanna ⁵, R. Uma Shaanker ¹

Affiliations
1 School of Ecology and Conservation and Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bengaluru 560 065, IN
2 Department of Crop Physiology, University of Agricultural and Horticultural Sciences, Shivamogga 577 201, IN
3 Ashoka Trust for Research in Ecology and the Environment, Royal Enclave, Srirampura, Jakkur PO, Bengaluru 560 064, IN
4 Centre for Structural and Functional Genomics and Biology Department, Concordia University, 7141 Sherbrooke West, Montreal, Quebec, H4B 1R6, CA
5 Department of Applied Botany, Kuvempu University, Jnana Sahyadri, Shankaraghatta, Shivamogga 577 451, IN

Abstract

Nothapodytes nimmoniana Graham (Icacinaceae) is a small tree distributed along a 1600 km mountain range in the Western Ghats biodiversity hotspot in southern India. The stem wood of N. nimmoniana accumulates high concentration (about 0.3% by dry weight) of the anti-cancer alkaloid, camptothecine (CPT). Several endophytic fungi isolated from this plant have been shown to produce camptothecine in vitro. In this study, we examined the diversity and distribution of fungal endophytes of N. nimmoniana along its entire distributional range in the Western Ghats and investigated if the CPT-producing endophytes are restricted to any specific clade. The leaf and stem of N. nimmoniana were sampled from 18 sites along the Western Ghats spanning 8-18°N lat. Endophytes were recovered from all sites with the colonization frequency ranging from 0% to 52% across the sites. One hundred and four endo-phytic fungal isolates were recovered from 118 plants and characterized both morphologically and by sequencing the internally transcribed spacer region of the nuclear rDNA gene. The fungal isolates belonged to 45 species (44 Ascomycetes and one Basidiomycetes). Fusarium and Hypoxylon were the most predominant genera comprising over half of the total isolates. Interestingly, CPT-producing endophytes were not restricted to any specific clade. We discuss these results in the context of the growing interest in endophytic fungi as possible alternative sources of plant secondary metabolites.

Keywords

Camptothecine, Endophytic Fungi, Fungal Diversity and Distribution, Nothapodytes nimmoniana.

Full Text

   

S. Shweta ¹, M. B. Shivanna ², B. R. Gurumurthy ³, R. Uma Shaanker ¹, T. R. Santhosh Kumar ⁴, G. Ravikanth ⁵

Affiliations
1 School of Ecology and Conservation and Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore 560 065, IN
2 Kuvempu University, Jnana Sahyadri, Shankaraghatta, Shimoga 577 451, IN
3 University of Agriculture and Horticulture Sciences, Shimoga 577 204, IN
4 Apoptosis and Cell Signalling, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram 695 014, IN
5 Ashoka Trust for Research in Ecology and the Environment, Royal Enclave, Srirampura, Jakkur PO, Bangalore 560 064, IN

Abstract

Camptothecine (CPT), a monoterpene indole alkaloid, is a potent inhibitor of eukaryotic topoisomerase I. It is produced by a number of plants, including Notha-podytes nimmoniana (Grahm) Mabb. (Icacinaceae), occurring naturally in the Western Ghats, India. The plant is inhabited by a number of endophytic fungi, many of which have been isolated and shown to pro-duce CPT, in culture, independent of the host. In this article, we examine the sensitivity of endophytic fungi isolated from N. nimmoniana to CPT. Contrary to our hypothesis that these fungi should be resistant to CPT (as they are exposed to host CPT as well as that pro-duced by themselves), we report that these fungi are sensitive and thus inhibited by CPT. We discuss these results in the context of the role of CPT in limiting endophytic fungal growth.

Keywords

Camptothecine, Endophytic Fungi, Nothapo-dytes nimmoniana, Sensitivity and Inhibition.

Full Text

   

G. Ravikanth ¹, M. R. Jagadish ¹, R. Vasudeva ², R. Uma Shaanker ¹, N. A. Aravind ¹

Affiliations
1 Ashoka Trust for Research in Ecology and the Environment, Royal Enclave, Srirampura, Jakkur Post, Bengaluru 560 064, IN
2 College of Forestry, University of Agricultural Sciences, Sirsi 581 401, IN

Abstract

There has been a growing concern about the increasing number of species that are globally threatened. Developmental projects, and increased dependence on forests both for sustenance and livelihood have rendered many species threatened. In the Indian context, more than 150 species are critically endangered and require immediate intervention to sustain their populations. A number of plant species are destructively extracted solely from the forests. Apart from anthropogenic threats, several species are threatened due to invasive species and climate change. In the light of increasing and continued threats, species recovery is the only viable option for restoring many of them from extinction. Here, we review the existing recovery programmes in the country and suggest a comprehensive approach in the conservation and recovery of many of the critically endangered species. We highlight issues that need to be addressed and discuss strategies for recovering the critically endangered species in the country.

Keywords

Endangered Plants, Ecological Interactions, Genetic Enrichment, Niche Modelling, Species Recovery.

Full Text

   

N. Lyngdoh ¹, S. Chakraborty ², G. Ravikanth ², A. A. Mao ³, A. K. Pandey ⁴

Affiliations
1 Department of Tree Improvement, College of Horticulture and Forestry, Central Agricultural University, Pasighat 791 102, IN
2 ATREE, Royal Enclave, Sriramapura, Jakkur Post, Bengaluru 560 064, IN
3 Botanical Survey of India, Kolkata 700 064, IN
4 College of Horticulture and Forestry, Rani Lakshmi Bai Central Agricultural University, Jhansi 284 003, IN

Abstract

Amentotaxus assamica D.K. Ferguson (common name: Chinese yew) belongs to the gymnospermic family Taxaceae. It is one of the two members of this family found in India, the other being Taxus wallichiana. Amentotaxus is a tall dioecious tree reaching a height of 20 m with horizontal or drooping branches. It is confined to small pockets in the Eastern Himalaya, specifically in Arunachal Pradesh, India. The tree finds usage for making pillars and posts in house construction. Following the ‘critically endangered’ status assigned to the species by the Conservation Assessment and Management Prioritization (CAMP) workshop (February 2003), attempts have been made to locate and assess its population status. Gajurel et al.¹ recorded 22 individuals along with five saplings and two seedlings from Mithumna, Dalai Valley, Arunachal Pradesh, the site from where the plant was first reported by F. Kingdom War in 1928. Das et al.² reported a fairly large population at Turoo forest, Sagalee subdivision, Pampum Pare district, Arunachal Pradesh, having tree density of 40 individuals/ha.

Full Text

   

Vikram Aditya ¹, P. S. Sumashini ¹, N. A. Aravind ¹, G. Ravikanth ¹, Chandrashekara Krishnappa ², R. Uma Shaanker ²

Affiliations
1 Ashoka Trust for Research in Ecology and the Environment, Royal Enclave, Sriramapura, Jakkur Post, Bengaluru 560 064, IN
2 School of Ecology and Conservation, University of Agricultural Sciences, GKVK, Bengaluru 560 065, IN

Abstract

India will surpass China as the world’s most populous country by 2050, with a projected population of 1.67 billion¹. Al-though the rate of population growth has decreased, the total fertility rate of 2.2 will keep India’s population growing for decades². The challenges posed by such increase in population to India’s food security, already under strain from land and resource scarcity, are enormous. Climate change and extreme weather events are already impacting agricultural production, disproportionately affecting vulnerable sections of society through higher food prices, lost livelihood opportunities, adverse health impacts and displacement.

Full Text

   

N. A. Aravind ¹, G. Ravikanth ¹

Affiliations
1 Ashoka Trust for Research in Ecology and the Environment, Royal Enclave, Srirampura, Jakkur PO, Bengaluru 560 064, IN

Abstract

No Abstract.

Full Text

   

M. Nobin Raja ¹, G. Ravikanth ²

Affiliations
1 Manipal Academy of Higher Education (MAHE), Manipal 576 104, IN
2 Ashoka Trust for Research in Ecology and the Environment, Royal Enclave, Srirampura, Jakkur Post, Bengaluru 560 064, IN

Abstract

Aquatic invasive species negatively impact the native aquatic communities in many parts of the world. Every nation faces the issue of introduced species, but the efforts to manage them depend on the varying capacity and willingness to manage invasions globally. Aquatic invasive species have their own set of challenges; it is crucial to understand the invasion dynamics of these species as well as their nature of interaction with humans to devise better mitigation processes. The freshwater aquatic wealth of India is seriously threatened by pollution, flow modification, overexploitation, habitat degradation and invasive alien species. India has several globally known freshwater invasive species. This article explores the invasion dynamics, potential pathways of invasion and impacts of the introduction of two of the world’s top 100 invasive species, which remain relatively unknown in India: Gambusia affinis and Gambusia holbrooki. In the early 19th century, Gambusia species were introduced into Lalbagh Lake, Bengaluru, and eventually to other parts of the country. Gambusia is now widely distributed in the wild and in many Protected Areas, where it has become a threat to endangered amphibians, fishes and other aquatic invertebrates. This article explores the distribution of these Gambusia species in India and the drivers leading to their invasion. It also explains the obscure history of Gambusia invasion in India and the lack of awareness of its possible negative impacts. The importance of using molecular tools in taxonomy and their applications in invasion ecology are discussed. This study highlights the research gaps in invasion ecology of this genus in India and suggests scientific methods to manage these invasive species.

Keywords

Aquatic Invasive Species, Biological Invasion, Gambusia affinis, Gambusia holbrooki, Molecular Tools.

Full Text

   

T. P. Sajitha ¹, G. Ravikanth ¹

Affiliations
1 Ashoka Trust for Research in Ecology and the Environment, Royal Enclave, Srirampura, Bengaluru 560 064, IN

Abstract

No Abstract.

Full Text

   

Monalisa Jena ¹, Manas Ranjan Mohanta ¹, Bipin Charles ², N. A. Aravind ², G. Ravikanth ², Sudam Charan Sahu ¹

Affiliations
1 Department of Botany, Maharaja Sriram Chandra Bhanja Deo University, Baripada 757 003, IN
2 Ashoka Trust for Research in Ecology and the Environment, Royal Enclave, Srirampura, Jakkur, Bengaluru 560 064, IN

Abstract

In the Anthropocene era, understanding the impact of climate change on niche shift, species distribution, and habitat change is increasingly important for the conservation of biodiversity. In this respect, species distribution models have been considered an important tool over the last decade. The present study illustrates distributional change, niche dynamics and climatic shifts of Saraca asoca (Roxb.) De Wilde in India, a proven medicinal plant and a listed threatened species by IUCN, under different climate change scenarios using MaxEnt. The robustness of the model was satisfactory (AUC = 0.936), indicating a good fit. There could be a significant gain in suitable habitat between the present and future scenarios, ranging from a minimum of 52,275.17 km² (RCP 2.6) to a maximum of 95,994.62 km² (RCP 4.5). In the future, the suitable habitat range would shift towards colder regions of India, where cultivation of S. asoca could be taken up, thus enabling effective management of the natural habitat and population of the species. This study will help understand the effects of climate change on S. asoca and its implications for conservation of the species.

Keywords

Climate Change, Distributional Changes, Ecological Niche Models, Niche Overlap, Saraca asoca.

Full Text