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

Fill in the blanks:
$(1)$ Maximum growth is observed in ........ phase.
$(2)$ Apical dominance is due to .......

What is a $Cactushouse$?

The following statements are given about plant growth hormones:
$I.$ Cytokinins suppress the synthesis of chlorophyll.
$II.$ Auxins control apical dominance.
$III.$ Gibberellins promote shoot elongation.
$IV.$ Abscisic acid enables seeds to withstand desiccation.
Which of the above statements are correct?

Match the following (Column-$I$ with Column-$II$):

Column-$I$	Column-$II$
$a.$ Ethephon	$(i)$ $GA$
$b.$ Terpene	$(ii)$ Ethylene
$c.$ Zeatin	$(iii)$ Natural auxin
$d.$ $IAA$	$(iv)$ Cytokinin

Factors which can modify geotropic responses are