Model Answer
0 min readIntroduction
Plant genetic resources (PGR) are the raw material for agricultural innovation, representing the diversity of plant species and their wild relatives. These resources hold genes crucial for traits like disease resistance, drought tolerance, and nutritional value. The erosion of PGR due to habitat loss and intensive agriculture poses a significant threat to food security. The FAO estimates that 75% of the world’s food is derived from just 12 plants, highlighting the vulnerability created by limited genetic diversity. Conservation of PGR is therefore paramount, enabling breeders to develop improved crop varieties adapted to changing environmental conditions and consumer demands.
The Significance of Plant Genetic Resources
PGR encompasses the genetic material of plants, including cultivated species, wild relatives, and their landraces. Their conservation is vital for ensuring food security, adapting to climate change, and enhancing nutritional value. Loss of PGR narrows the genetic base of crops, making them more susceptible to pests, diseases, and environmental stresses.
Methods of Conservation
There are two primary methods for conserving PGR: ex situ and in situ conservation.
Ex Situ Conservation
Ex situ conservation involves the removal of plant material from its natural habitat and maintaining it under controlled conditions. This includes:
- Seed Banks: These store seeds under cryogenic conditions, preserving genetic diversity for future use. The Svalbard Global Seed Vault in Norway serves as a “doomsday vault” for PGR.
- Field Genebanks: These maintain living collections of plants, allowing for propagation and observation of traits.
- In Vitro Collections: These utilize techniques like tissue culture to conserve plants, particularly those that do not produce viable seeds.
In Situ Conservation
In situ conservation focuses on protecting plants within their natural ecosystems. This includes:
- Protected Areas: National parks, wildlife sanctuaries, and biosphere reserves provide habitats for wild relatives of crops.
- On-Farm Conservation: Supporting farmers who maintain traditional varieties and landraces. India's NBPGR (National Bureau of Plant Genetic Resources) actively promotes this.
Role in Crop Improvement
Conserved PGR plays a crucial role in crop improvement through several mechanisms:
- Source of Novel Genes: Wild relatives often possess genes for traits absent in cultivated varieties. These can be introduced through conventional breeding or genetic engineering.
- Disease and Pest Resistance: Conserved germplasm provides a reservoir of resistance genes to combat emerging threats. The development of Bt cotton utilized genes from Bacillus thuringiensis.
- Adaptation to Climate Change: Wild relatives and landraces often exhibit tolerance to drought, salinity, and extreme temperatures.
- Nutritional Enhancement: Conserved PGR can be used to biofortify crops, increasing their micronutrient content (e.g., iron and zinc).
Challenges and Future Directions
Challenges include limited funding for conservation efforts, biopiracy concerns, and the need for improved accessibility of PGR to breeders. International collaboration through initiatives like the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA) is essential for ensuring equitable access and conservation of PGR.
| Conservation Method | Description | Advantages | Disadvantages |
|---|---|---|---|
| Ex Situ (Seed Banks) | Storing seeds under cryogenic conditions | Long-term storage, cost-effective | Loss of genetic context, requires infrastructure |
| In Situ (Protected Areas) | Protecting plants within natural habitats | Maintains ecological context, conservation of biodiversity | Vulnerable to habitat destruction, difficult to manage |
Conclusion
In conclusion, plant genetic resources conservation is a cornerstone of sustainable agriculture and food security. The combined application of <em>ex situ</em> and <em>in situ</em> conservation strategies, coupled with advancements in biotechnology, is vital for ensuring a resilient and diverse food supply. Strengthening international collaborations and promoting farmer participation in conservation efforts are crucial for safeguarding these invaluable resources for future generations.
Answer Length
This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.