KAU Agri Infotech Portal

Onion (Allium cepa L.)

In systemic infection occurs when the plants are raised from the diseased bulbs, the seedlings and plants remain stunted, become distorted and pale green with downy fungal growth.
In localized infection, symptoms appear on the surface of leaves or flower stalk as violet growth of fungus, which later becomes pale greenish yellow and finally the leaves or seed stalks collapse.

Select healthy bulbs for seed production.
Follow crop rotation for 3-4 years with non-host crop.
Crop sanitation: Dispose properly the infected crop debris and refuse heaps of garlic culled from storage.
Avoid late planting, poor drainage, higher doses of fertilizers and frequent irrigation.
Use resistant varieties.
All weeds serving as collateral host of the fungus should be removed and destroyed.
Onion bulbs meant for seed crop should be exposed to sun for 12 days to destroy the fungus.

Sl.No	Generic Name	Trade Name	Color code	Dosage/litre	Knapsack Sprayer (Capacity 10L)	Recommendation		Remarks
Sl.No	Generic Name	Trade Name	Color code	Dosage/litre	Knapsack Sprayer (Capacity 10L)	Dosage/acre (200 L)	Dosage/hectare (500 L)	Remarks
1	Potassium phosphonate 40 SC	Akomin	Green	4 ml/ litre of water	40 ml	800 ml	2000 ml	-
2	Mancozeb 75 WP	Devidayal M-45, Dhanuka M 45, Dhanuka M-45, Dithane, Dithane M-45, Hilthane, Hindustan M 45, Indofil M 45, Izeb M-45 Manzate, Luzen-45, Macoban, Macoban M-45, Mancosaan, Mancosaan M-45, Maneb Manzane, M-Guard, Savour M 45, Tata M-45 Eurofil-NT, Uthane M-45, Veera, Zinthane	Green	3 g/ litre of water	30 g	600 g	1500 g	-
3	Copper hydroxide 77 WP	HiDice, Kocide 101	Blue	1 g/ litre of water	10 g	200 g	500 g	-
4	Copper oxychloride 50 WP	Bensaan, Blitox, Blue copper, Bluetrox, Copter, Cupramar, Cuprina, Dhanucop, Fytolan, Fytox, Fytran, Fytolan, Hilcopper, Killex copper, Maincop Dhanucop, Star cop, Tagcop, Trucop	Blue	2 g/ litre of water	20 g	400 g	1000 g	-