Calcium deficiency in tomato causes BER and fruits with BER having Ca level of . . . . . . . . %.

Calcium deficiency in tomato causes BER and fruits with BER have Ca level of > 0.2%.
BER is Blossom end rot and is caused by a calcium deficiency, usually induced by any disruption of water uptake.
Lack of water, even short-term, especially after heavy rainfall, will result in reduced calcium intake. High humidity, which causes a reduction in evapotranspiration and water uptake in plants, will have the same effect.