Tomato problem

[khabbab]

Is this some pest on my beefsteak tomatoes or some disease? Do i need to spray something? I sprayed imidacloprid 20 days ago to kill winged aphids on this plant, is this some side effect?

[Farhan Ahmed]

Possibly Blossom-end rot

Extracts
"An early symptom of blossom-end rot is a light tan patch on the blossom end of the green fruit. Over time the area turns dark brown or black and may become sunken or leathery. Fruit that is one-third to one-half developed is most commonly affected. Sometimes an internal black rot will develop in the center of the fruit with little or no external symptoms."

Caused by anthracnose/fungus due to warm humid conditions.....which we had due to rains i think

[khabbab]

Alright if it is Blossom end rot, what can i do to prevent my remaining or future tomatoes?

[Farhan Ahmed]

Firstly the leading factor is fruit cracking which is caused by calcium deficiency, caused by various reasons.

Difficult to control, apply calcium immediately to prevent fruit cracking.
Remove affected fruits.
Ensure good drainage and dry conditions