WEED MANAGEMENT

2. Crop
Competition
Intra-
specific
competition
Intra-
specific
competition

3. Weeds compete with the crop for
following growth factors
Nutrients Moisture
Light Space

4. Critical period of crop weed
competition in important field crops
Sr. No. Crops Critical periods % Reduction in
grain yield
1. Rice 30-45 15-40
2. Wheat 30-45 20-40
3. Maize 15-45 40-60
4. Cow-pea 15-30 15-30
5. Soybean 20-45 40-60
6. Groundnut 40-60 40-50
7. Sugarcane 30-120 20-30