How to prevent pink root rot disease in onions

The main symptom of this disease is onion roots becoming pink.
When the infection is high, the roots become black and dry.
Due to this, the growth of tubers is greatly affected.
It is very important to use the following products to prevent this.
Use Kitazin 48% EC @ 400 ml/acre or Thiophanate Methyl 70% W/W @ 300 gram/ acre.
Use Trichoderma viride @ 500 gram/acre as soil treatment and Pseudomonas fluorescens @ 250 gram/acre as spray as biological treatment.