The movement of auxin is largely

$A$: $2, 4-D$ is widely used by farmers in agricultural and horticultural practices.
$R$: Flowering in most plants can be initiated by using high concentration of Auxin.

Which of the following accelerates apical meristem and exerts direct effect on the growth of plant axis in length?

$A$ substance which accelerates the growth in stem is

Who isolated auxin from tips of coleoptiles of oat seedling?

The plant hormone used to destroy weeds in a field is: