Tree Physiology
The Tree Physiology Department carries out seed physiological and biochemical studies of recalcitrant seeds; Developing Protocols for clonal and Seed propagation of Threatened trees, Non-timber forest products (NTFPs, Fast growing Indigenous trees, lesser-known wild fruit trees; Climate change impact on endemic and threatened trees; Restoration and population size enhancement of threatened Species, etc. comes under the domain of the Department of Tree Physiology.
The broad areas of research of the Department include:
- Endemic and threatened Trees/Ecosystems and Climate change:
The climate change-induced threats are a major physical constraint the species face in their habitats. Forests have been stressed by long-term regional warming and drying trends, which have affected the habitat-specific endemic and threatened trees, more precisely, the functional dynamics of the species. Studies on phenology, reproductive biology, biotic interactions and natural regeneration of the species are significant in identifying and correlating the impact of climate change on species and developing suitable mitigation strategies. The Department has initiated a study on selected red-listed trees in the Western Ghats to address the issue.
- Macro propagation of Red listed and NTFP trees
One important task in forestry research is producing adequate planting stock for afforestation/ restoration programmes. Therefore, developing vegetative/ seed propagation protocols is prioritised, whereas most red-listed and non-timber forests produce yielding trees that need more seed and nursery technologies. Vegetative propagation is advantageous for plants with either a poor fruit set or a short period of seed viability. Being dioecious by nature, the production of female progenies is also not ensured for certain species, adding merit to selective breeding methods. The categorisation of seed type, critical moisture content for maintaining seed viability and subsequent storage practices for extended seed longevity are prerequisites for germplasm storage of potential species. The Tree Physiology Department recently completed propagation studies on red-listed tree species viz - Myristica spp., Kingiodendron pinnatum, Vatica chinensis, Hydnocarpus macrocarpa, Cynometra sp. etc.
- Biochemical and physiological studies of recalcitrant seeds
The challenge of recalcitrancy, or the rapid loss of seed viability among forest seeds, is a complex and multifaceted issue in tropical forestry, particularly in the context of climate change. The exact cause of viability loss in recalcitrant seeds is the result of a complex interplay of metabolic processes. The exposure of seeds to extreme temperatures leads to structural changes at cellular and tissue levels, as evidenced by increased ion, sugar, and protein leakage. Therefore, the identification and estimation of biochemical factors affecting seed viability loss, and the subsequent development of management strategies for improved utilization of tree resources, require the expertise of our audience. Our study focuses on threatened and economically important species such as Dysoxylum malabaricum, Persea macrantha; wild edible fruit plants, Baccaurea courtallensis and Flacourtia montana.
- Ecological restoration of Red listed and NTFP trees
After studying ecology and biology, ecological restoration of a species can help create new populations through reintroduction or rebuild degraded populations in their natural habitats through restocking. The dedicated scientists in the Department have made significant efforts to enhance the genetic base of red-listed and NTFP trees in the Western Ghats. Species such as Hydnocarpus macrocarpa, Drypetes malabarica, Myristica malabarica, Myristica beddomei, Myristica magnifica, Gymnacranthera farquhariana, Kingiodendron pinnatum, etc. are a few examples of this line of activity.
