What type of disease is Rickets?

Deficiency of which mineral element causes the dormancy of lateral buds?

Deficiency symptoms of mineral elements appear first in young leaves. - $P$
Deficiency symptoms of mineral elements appear first in senescent (older) leaves. - $Q$
$P$ and $Q$ are respectively:

The deficiency of calcium is observed in the absence of vitamin ...............

Which of the following is deficient in the soil of Gujarat,$U$.$P$.,and Maharashtra in a large area?

Yellowish edges appear in leaves deficient in $....$