$Cuscuta$ is a

The abscission layer is covered by a leaf scar which is composed of

When tropical plants are shifted to temperate climate,they do not grow. This is due to

Wound hormone is called

Match the following:
Column-$A$ | Column-$B$
$(1)$ Auxin | $(I)$ Ripening and maturity of fruits
$(2)$ Gibberellin | $(II)$ Differentiation of xylem elements
$(3)$ Cytokinin | $(III)$ Prevention of genetic and physiological dwarfism
$(4)$ Ethylene | $(IV)$ Found from tumour tissue of tobacco

Match the following:

Column $I$	Column $II$
$a.$ Auxin	$(i)$ Root hair formation
$b.$ Cytokinin	$(ii)$ Seed development
$c.$ Ethylene	$(iii)$ Xylem differentiation
$d.$ $ABA$	$(iv)$ Nutrient mobilisation