Crop wild relatives are wild relatives of cultivated plants. These are genetically related to a domesticated plant. They grow at geographically wild landscapes and have evolved with time on their own due to extreme environments.
With the domesticated plant these could be either related as belonging to same species (from which the plant was domesticated) or belonging to same genus. Almost every species of plant that we humans have domesticated and cultivate has one or more crop wild relatives. Early signs of domesticating wild plant species were dates back 10,500 years in Western Asia and since then domestication is being practiced around the world by different groups of people on many CWRs.
Duration and intensity of the domestication process depends upon the type of crop.
In general, all the crops that are cultivated today had been originated from (one or more) wild and naturally occurring species. This process started with collecting particular wild grasses or legumes, than followed by their cultivation under more controlled conditions and gradually undergoing transformation from wild into domesticated plants.
CWR relation with domesticated plant could be in 2 ways:
1. The crops are man - made hybrids between 2 wild ancestors
2. There could be no difference between them as both are subspecies of same genus.
Thus, CWRs can be termed as the progenitors or ancestral species of our present crops, and are a valuable resource of genetic diversity and traits for plant breeding.
Importance of CWRs:
CWRs are important components of natural and agricultural ecosystems and are responsible for maintaining ecosystem health.
CWRs are gene pools; they have a variety of traits which can help in more efficient agriculture practices and more healthy production.
They have trait diversity like drought tolerance, pest resistance that farmers and breeders can cross with domesticated crops to produce new varieties.
They help in increasing the yield and nutritional quality of the produce.
The plants can be crossed through:
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Natural way: Farmers often plant them alongside domesticated crops to promote natural crossing of beneficial traits.
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Artificial way: In lab, through breeding programs, hybridization etc.
Their conservation and sustainable use is very important for improving agricultural production, increasing food security, and maintaining a healthy environment.
Some people also gather them from wild and eat it.
For years crop wild relatives have contributed to crop domestication, but nowadays due to over exploitation of natural resources by humans they are in vulnerable state and need to be protected.
In response to the "threatened state" of crop wild relative, Crop Trust popular as the Global Crop Diversity Trust (an international nonprofit organization) has started a campaign to collect, conserve and to use the wild relatives.
The aim of this initiative is identifying those wild crop varieties that are missing from crop collections (already existing), are likely to contain traits or characteristics of value that can make agriculture more productive, and the most endangered.
The crop varieties are then collected from the wild and conserved in gene banks; evaluated for useful traits and prepared for use in breeding programs.
Also, the conservation strategy mostly used for CWR's conservation is ex- Situ conservation. The progress of in - Situ conservation is quite slow as the management standards there are quite low.
