Please house,, what is responsible for this and how can one fix it?

Amao Samson It will cover don't worry. Give better fertigation

Venkat Pawar. Thanks. Any suggestions on what nutrients to focus on to fertigate?

Amao Samson I agree with Samira Ghouil سميرة غويل.

Amao Samson During harvesting stages I follow following ferrigation schedule. Picking Stage 1. 00:52:34 4 Kg 2. Calcium Nitrate 3 Kg + 13:00:45 2 Kg + Fe100 gm 3. Potassium Sceonite 4 Kg + Boron 500 gm 4. 13:40:13 3 Kg +00;00:50 2 Kg 5. 00:00:504 Kg + Micronutrients TMX2 200 gm। 6. 19:19:19 3 Kg+ Magnesium Sulphate 2 Kg + Boron 500 gm। 7. Continue above schedule upto end. 8. Usually Calcium deficiency is prominent during picking stage, so carryout sprays of Calcium EDTA1 gm + Boron1 gm per liter at an interval of 6 days. 9. Micronutrient sprays should be regularly carriedout at weekly intervals.  Note: 1. Fertigation in above mentioned sequence at alternate days. 2. Above schedule is of 4000 sq.m