Non parasitic disorder due to deficiency of Ca in tomato is

Non Parasitic disorder due to deficiency of calcium in tomatoes is BER (Blossom end rot).
The problem occurs when tomato plants have grown rapidly during the early part of the season and are then subjected to hot dry weather when the fruits are in an early stage of development. However, too much water such as heavy irrigation may also bring on the problem.
Symptoms first appear as a water-soaked spot near the blossom end of the fruit, later the spot becomes brown and enlarges.