Life Sciences & Biotechnology
Title : | Photobiont diversity in lichens occurring in varied ecological conditions in India |
Area of research : | Life Sciences & Biotechnology |
Focus area : | Ecology and Biodiversity |
Principal Investigator : | Dr. Sanjeeva Nayaka, CSIR-National Botanical Research Institute, Lucknow, Uttar Pradesh |
Timeline Start Year : | 2024 |
Timeline End Year : | 2027 |
Contact info : | nayaka.sanjeeva@gmail.com |
Details
Executive Summary : | The lichens are symbiotic association between a fungus (mycobiont) and a photosynthetic partner (photobiont, either green alga or cyanobacteria). The mycobiont forms the outer cover giving shape, structure and color to the lichen thallus that encloses photobiont. The photobionts in lichens were long time ignored by lichenologists for several reasons. 1. lichenology is traditionally considered a sub-discipline of mycology or botany, so mycologists merely focus on the mycobionts. 2. a great scarcity of trained phycologists competent enough to study the algae associated with lichens as they undergo severe modifications. 3. fungal partner is dominant component of lichen thallus while photobiont has negligible portion. There are about 20,000 species lichens or lichenized fungi are identified throughout the world, whereas photobionts are only 156 species. In most of the cases the photobionts are never identified up to their species level. The integrity and evolution of lichen symbioses depend on a fine-tuned combination of photobiont and mycobiont. It was thought that the association between two partners is very specific. The molecular studies have revealed that the lichen photobiont can also be free living in nature. A vegetatively reproducing lichens by having both mycobiont and photobiont cells likely to have same species of photobiont species everywhere they occur. Whereas in case lichens reproducing through sexual or asexual spores the fungus has to pick its compatible photobiont from the surroundings. The lichens are either restricted or cosmopolitan in distribution. In case of cosmopolitan species, especially the one that reproduces by spores, a fungus may not get a same photobiont from its surroundings due to the varied ecological conditions. Therefore, it is possible that a lichen species growing in different ecological conditions can have different species/ stains/ lineage of photobionts. The proposed study aims to understand the photobiont selection and specificity in lichen forming fungi growing in varied ecological conditions. The study also tries to explore utilization of photobionts as taxonomic characters in identification of lichens. The study will be carried out taking three species of lichens with different modes of reproduction, but with cosmopolitan distribution. The proposed lichens are Parmotrema reticulatum (soredia), P. tinctorum (isidia) and P. melanothrix (spores). However, study will not be restricted only these three species. The lichen for study will be collected from throughout India. The total DNA extracted from lichen tissue will be utilized for photobiont ITS1, 5·8 rDNA, ITS2 and rbcL region amplification and sequencing. The BLAST and phylogenetic analysis of both ITS and rbcL using Bayesian and maximum likelihood (ML) approaches. The similar approach will be also carried out for ITS genes of mycobiont. The photobiont characterization will be carried out under light microscope and TEM. |
Total Budget (INR): | 30,62,059 |
Organizations involved