2. Composed By: Ahmed Mukhtar
2013-ag-3660
University Of Agriculture Faisalabad (UAF)
and
Barani Agricultural Research Institute (BARI)
Chakwal
3. Weed
A weed is a plant growing out of its place.
A wild plant growing where it is not wanted
and in competition with cultivated plants.
4. Introduction
There are over 30,000 species of weeds round the
world. Out of these about 18,000 are known to
cause serious losses.
In the list of world’s worst weeds Dela (cyperus
rotundus) ranks first and Khabbal grass (cynodon
dactylon) second position.
30-35% yield losses due weeds.
47. Preventive Measures of Weed Control
1. Use clean seed.
2. Use well decomposed compost and F.Y.M.
3. Remove the weeds before formation of flowers.
4. The cropped area, bunds irrigation channels, waste lands, public
places etc. should be kept clean or free of weeds.
48. Cont…
5. Do not permit the livestock to move from weed infested area to clean
area.
6. Farm implements and machinery should be properly cleaned e.g
i- Cultivator
ii- Harvester
7. Keep threshing yard, compost and F.Y.M. Pits free from weeds.
8. Follow the legal and quarantine measures while importing crop seeds,
food grains , seedlings etc.
49. Methods of weed control
i Cultural
ii Biological
iii Chemical
iv Integrated
50. • Hand weeding
• Mechanical weeding (animal-drawn weeders & machine-power weeder.
• Mulching
• Crop Rotation
• Tillage
• Burning
• Flooding
• Sowing/planting time and crop spatial management
• Crop genotype choice
• Cover crop (used as Living mulches)
• Intercropping
• Fertilization
Methods of Weed Control
60. Biological Weed Control
Biological weed management refers to the use of
biological agent to control weeds.
Pest
Predators
Pathogen
Parasites
61. CHEMICAL WEED CONTROL
Herbicide(s), also commonly known as weed-
killers, are chemical substances used to control
unwanted Plants.
Selective herbicides
Non-selective Herbicides
Broad-range herbicides