Write an explanatory note on Ex situ conservation.

Ex situ (off site) conservation approach involves placing the threatened animals and plants in special care units for their protection.

Ex situ conservation includes off site collections and gene banks.

off site Collections : They are live collections of wild and domestic species in Botanical gardens, Zoological parks, Wildlife safari parks etc.

India has $355$ parks, where animals which have become extinct in the wild continued to be maintained and has $35$ Botanical Gardens where plant species are protected.

Gene Banks : These are the places where protection and maintanance of gametes is done by stocking of viable seeds (seed bank), tissue culture and frozen germplasm with the whole range of genetic variability. These are as follow :

$(a)$ Seed Bank: The storage of different genetic strains of commercially important plants in the form of seeds is one of the most widespread and valuable ex situ approaches of the conservations strategy.

$(b)$ Tissue culture : Plant tissue culture is widely used to produce clones of a plant in a method known as micropropagation.

This method is useful in maintaining a large number of genotypes in small area, rapid multiplication of even endangered species and for hybrid rescue. eg. banana and potato.

$(c)$ Cryopreservation : It is a method of in vitro conservation in liquid $\mathrm{N}_{2}$ at temperature of $-196^{\circ} \mathrm{C}$ (-130 $\left.{ }^{\circ} \mathrm{F}\right)$ in a controlled rate freezer for vegetatively propagated crops and storing other biological material.