Genetic Erosion a major threat for biodiversity
Within the altercation of global biodiversity, genetic erosion is rarely considered. Extinction is more important in the discussion of biodiversity.
Every species which goes extinct result in the extinction of many populations. Whereas extinction is a well sketch term which is playing a principal role in the discussion of global biodiversity since almost 1980, genetic erosion is still an elaborating concept. Its origin can be trace back in 1890 when scientists emphasis the significance of landraces for the future work of breeding.
By the growth of scientiﬁc plant breeding scientist speak about the extinction of the old beneficial landraces in process of making new varieties and also makes a universal approach in regions with applicable material. This precocious prediction of future destruction has been basically overlooked. American plant explorers in 1936 are awarded with the ﬁrst understanding the case of genetic erosion.
The word erosion is evocative to the step by step extinction of something significant that will sooner or later weaken the stability, health of communities or dependent individuals. Likewise in genetic diversity it is the gradual destruction of genetic diversity in a specie. It can occur quite quickly with catastrophic circumstance or modification in use of land that eliminates considerable amount of individuals and also their habitat.
But this erosion can also happen more gradually and remain unnoticed for long period of time. Genetic erosion can depict the loss of whole populations and is differentiated from others genetically, the change in the frequency of some specific alleles in populations or in entire species, or misplacement of some allele combinations. Genetic erosion is the matter of concern because it involves the loss of genetic diversity in plants and such loss can have harmful effect on environment.
Genetic diversity is significant to the viability, fitness of specie. Genetically less diverse populations of plants can be much exposed in certain cases to environmental stress or other pathogens. Populations which are genetically eroded are less competitive with some invasive species. Overall, genetic erosion can have cascading consequences over the whole ecosystem.
Some natural conditions like genetic drift and natural selection may result into loss of genetic diversity. Whereas these genetic losses are mostly not catastrophic and are frequently balanced by gene flow and mutation, and normally do not occur in concert across the entire species. Usually, species that were widespread and have lost their diversity and habitat are usually have serious risk to loss of genetic diversity than to species which are naturally limited in their occurrence.
Impact that could contribute to the genetic erosion in indigenous plant species which include: habitat fragmentation, major loss of habitat and resident plant populations, some management activities like nursery selection, harvesting or thinning of plants, and the narrow genetic collection of planting material in revegetation efforts.
Genetic erosion can be studied at many levels in the range of management activities. In order to avoid major fragmentation and loss of habitat, some guidelines can be followed up to minimize the risk of genetic erosion in some species of native plants.
Collection of seeds and propagation materials for example cutting in such a way that genetic diversity of that area will conserved. These collections set down the geographic provenance, total parent plants, number of seeds per plant and their distance. Life history of plant species will assist to guide suitable genetic collections.
Like, if species are dioecian and collection is vegetative material instead of seeds then genetic collection must show balance between males and females. If plant species reproduce asexually it is significant to collect from different clones.
While purchasing plants from nursery always try to get geographic source information as well as methods of collection and conditions to grow plants, it will help to find whether our collection has enough genetic diversity or not.
While planting cultivars of some native species always be careful. There is huge interpretation in genetic diversity of plants that are merchandise as cultivars depends upon the original collection and the process it has experience first to release.
Genetic erosion does not occur if cultivars are use. If cultivars are from narrow genetic base and is use broadly to substitute original populations of plant or planted in a very large numbers where interbreeding more probably to occur this might contribute to genetic erosion of some native plant populations.
Support and encourage the activities of nursery management that target to maximize the seeds portion that will turn into healthy plantable seedlings. Some good nursery managements which are based on the awareness of genetic variation include germination requirements, seed characteristics and patterns of growth which includes the measures to excluded selection and lower the effect on genetic diversity of the original collection.