Gray speck disease in oats takes place by the deficiency of

Premature leaf fall is caused due to the deficiency of

Chlorosis occurs when plants are grown in

How are the terms 'critical concentration' and 'deficient' different from each other in terms of the concentration of an essential element in plants? Can you find the values of 'critical concentration' and 'deficient' for minerals $Fe$ and $Zn$?

Deficiency of which group of elements can cause inhibition of cell division in plants?

Fall of immature leaf is due to the deficiency of