Agriculture
Weed Management :: Integrated Weed Management

Integrated weed management

Rice

Critical period of  weed control 20-30 DAT
Cultural method 1) Hand weeding
2) Hand pulling
3) Pudding
4) Flooding
Mechanical method 1) Weeder (Float)
2.Conoweeder/Rotary weeder
Chemical method Apply pendimethalin 1.0kg/ha on 5 days after sowing or Pretilachlor + safener (Sofit) 0.45kg/ha on the day of receipt of soaking rain followed by one hand weeding on 30 to 35 days after sowing.
Biological method 1. Hirsch – Manniella spinicaudata is a rice root nematode
     which controls most upland rice weeds
2. Azolla
Remarks I. Substitution and preventive method:
a) Stale seed bed technology
b) Land preparation
c) Water management

WHEAT

Critical period of  weed control 15 – 30 DAS
Cultural method a) Hand Hoeing
b) Inter cultivation
c) Criss-cross sowing
Chemical method 1. 2, 4D (1 – 1.5 kg ai/ha)
2. Mixture of Isoproturan (0.75 kg ai/ha) and
    2, 4D (0.4 kg ai/ha) during 30- 35 DAS
Remarks II. Complimentary weed control methods
a) Cultivars
b) Seedling age /planting method
c) Fertilizer management
d) Cropping system

 SORGHUM

Critical period of  weed control 21 – 42 DAS
Cultural method
  1. Hoe and hand weed on the 10th day of transplanting if herbicides are not used.
  2. Hoe and weed between 30 - 35 days after transplanting and between 35 - 40 days for a direct sown crop
Chemical method
  1. Apply the pre-emergence herbicide Atrazine 50 WP - 500 g/ha on 3 days after sowing as spray on the soil surface
  2. If pulse crop is to be raised as an inter-crop in sorghum do not use Atrazine.
Remarks 1. Inclusion of cotton crop in the rotation

MAIZE

Critical period of  weed control Maize 2 to 6 Weeks
Cultural method One hand weeding on 40-45 days after sowing
Chemical method

1. Pre-emergence application of Atrazine (1-2 kg ai/ha)
2. Combined application of Alachlor (2 kg/ha) and atrazine
     (1kg/ha) is more effective and have wider spectrum of
      control

GROUNDNUT

Critical period of  weed control Upto 45 days
Cultural method After 35 - 40 days one hand weeding may be given.
Chemical method 1. Alachlor (1-5 kg/ha) – pre emergence application

 SUNFLOWER

Critical period of  weed control 4-6 weeks
Cultural method Hoe and hand weed on the 15th and 30th day of sowing and remove the weeds. Allow the weeds to dry for 2 - 3 days in the case of irrigated and then give irrigation.
Chemical method 1. Apply Fluchloralin at 2.0 l/ha before sowing and incorporate or apply as pre-emergence spray on 5 day after sowing followed by irrigation or apply Pendimethalin as pre-emergence spray 3 days after sowing.

COTTON

Critical period of  weed control First 45 days
Cultural method
  1. One hand weeding on 45 DAS will keep weed free environment upto 60 DAS
  2. Hoe and hand weed between 18th to 20th day of sowing, if herbicide is not applied at the time of sowing
Chemical method 1. Diuron (0.5 – 1.5 kg/ha), Monuron (1-1.5 kg/ha),
    Fluchloralin (1-1.5 kg/ha) applied as preemergence/
     preplanting

PULSES

Critical period of  weed control First 30-35 days
Cultural method
  1. One hand weeding on 30 days after sowing gives weed free environment throughout the crop period
  2. If herbicides are not applied give two hand weedings on 15 and 30 days after sowing.
Chemical method 1. Fluchloralin (1-1.5 kg/ha ), Pendimethalin (0.5-1.0 kg/ha) as Pre emergence (preplanting incorporation)

 TOBACCO

Critical period of  weed control First 9 weeks
Chemical method 1. Fluchloralin (2-3 kg/ha), Pendemethalin (1-1.5 kg/ha) as
    pre-emergence application

SUGARCANE

Critical period of  weed control 4 to 5 months
Cultural method Remove the weeds along the furrows with hand hoe. 
Mechanical method If herbicide is not applied work the junior-hoe along the ridges on 25, 55 and 85 days after planting for removal of weeds and proper stirring
Chemical method 1. Pre-emergence herbicides like atrazine (2 to 3 kg/ha)
     Simazine (2 to 3 kg/ha), Alachlor (1.3 to 2.5 kg/ha) etc.,
     will generally last for 8 to 12 weeks
2. To obtain best results sequential application of  
    Preemergence and post emergence herbicides or post
    emergence herbicides like Glyphosate (0.8 to 1.6 kg/ha)
    Paraquat (0.4 to 0.8 kg/ha).