Critical Period of Crop–Weed Competition

Crop	Critical Period (Days)	Reduction in Grain Yield (%)
Cereals
Paddy – Direct sown	20 – 45	15 – 90
Paddy – Transplanted	30 – 45	15 – 40
Paddy – Upland condition	Entire period	40 – 90
Wheat	30 – 45	20 – 40
Maize	15 – 45	40 – 60
Sorghum	15 – 45	15 – 40
Pearl millet	30 – 45	15 – 60
Pulses
Pigeonpea	15 – 60	20 – 40
Greengram	15 – 30	25 – 50
Blackgram	15 – 30	30 – 50
Cowpea	15 – 30	15 – 30
Chickpea	30 – 60	15 – 25
Peas	30 – 45	20 – 30
Lentil	30 – 60	20 – 30
Oilseeds
Soybean	20 – 45	40 – 60
Groundnut	40 – 60	40 – 50
Sunflower	30 – 45	30 – 60
Castor	30 – 50	30 – 35
Safflower	15 – 45	15 – 40
Sesamum	15 – 45	15 – 40
Rapeseed–mustard	15 – 40	15 – 30
Linseed	20 – 45	30 – 40
Commercial Crops
Sugarcane	30 – 120	20 – 30
Potato	20 – 40	30 – 60
Cotton	15 – 60	40 – 50
Jute	30 – 45	50 – 80
Vegetable Crops
Cauliflower	30 – 45	50 – 60
Cabbage	30 – 45	50 – 60
Okra	15 – 30	40 – 50
Tomato	30 – 45	40 – 70
Onion	30 – 75	60 – 70