Reproducing new plants by cells instead of seeds is known as

Whose spores are non-motile ?

Which of the following is true/correct option about 'terror of Bengal'?

$(I)$ It is the aquatic plant

$(II)$ It is the invasive weeds

$(III)$ It does not drain oxygen from the water which leads to death of fish

$(IV)$ It can propagate vegetatively

Plants identical to mother plants can be had obtained from

The reason of formation of embryoid from pollen grain in a tissue culture medium is