Bulb treatment: Treat the onion bulbs with Bavistin (or) Dithane M75 (Mancozeb 75% WP) at 2 – 2.5 gm/litre water for 5 – 10 minutes before sowing.  This will help prevent the bulbs infection from soil borne pathogens.
Seed treatment: The seeds are treated with Vitavax powder (Carboxin 37.5% + Thiram 37.5% DS) at 3 gm/kg seed per acre or treat with BACF TRIDENT (Tricoderma viride 1.5%WP) at 4 gm/kg seed is also recommended to manage damping off and raise healthy seedlings.