Gene Pool? Genetic resources? Hard to digest? Not Anymore

Our environment comprised of many natural treasures. Like water, plants. Humans, animals to microorganisms. All these collectively forms Bio-Diversity. Among these plant kingdom occupies a major chunk. Again, among these plant families many are used for agricultural to human consumption purpose All these plants or crops along with other agriculturally related organisms builds Agro-Biodiversity.

Now, let’s think about any crop that grown around us. Are they all uniform in all character? Well, No. Every crop has its own characters which exhibits many variations in respect to environment, geographical locations, even to microclimates. Feeling hard?

Ok. Let’s make it simple. Suppose, rice/wheat is one of the important foodgrain we take primarily in India. Now if we look for the characters of the plant we might see some of the rice/wheat plants are tall while some are short. Some of them exhibits aroma and some do not.

That means even in one crop there may be variation in characters in some location and with different location this variations are much larger. All these variations constitutes Genetic Resource of that plant for that place. These genetic resources are nothing but the Gene Pool. That was easy, right?

Genetic resources are the basic blocks that builds foundation of crop improvement. Now which are the basic constituents of the genetic resources or gene Pool? Those are wild relatives occurring in nature, related weed species, cultigens etc. Now, wait. Cultigens. What does that mean? Cultigens are nothing but the land races, putative ancestral forms, primitive cultivars, obsolete cultivars, improved varieties etc. Not only cultigens, even farmer’s traditional selections, genetic stocks, parental lines of hybrids and last but not the least GMOs (genetically modified organisms) and transgenic plants.

Read more: What GMOs are and what are Transgenics?

These Gene Pool or genetic resources are of 4 (four) types.

a)    Primary Gene Pool, often termed as GP1.

b)    Secondary Gene Pool, often termed as GP2.

c)    Tertiary Gene Pool, often termed as GP3.

d)    Quaternary Gene Pool, often termed as GP4.

·         GP1 comprised of closely related species or same species where intermating is easy and upon crossing produces fertile offspring. Complete chromosome pairing & easy Gene exchange occurs within the lines through crossing.

·         GP2s are little distant. F₁ shows partial fertility on crossing with GP1. Pollination is difficult here and therefore embryo culture is needed. Gene exchange is possible but is difficult.

·         GP3 are more distant species and produces only steriles when crossing with GP1. Normally gene exchange is very difficult and only possible through special techniques like tissue culture.

·         GP4 is the most distant species and are completely sterile. Normal crosses or tissue culture is not possible here. Only Bio-technological tools can be used.

Now possibly Genetic Resource is a piece of cake for you.