Nursery weeds are unwanted plants in a nursery which reduce availability of moisture, nutrients, sunlight and growing space to the seedlings.

1
Introduction

• Nursery weeds are unwanted plants in a nursery
  which reduce availability of moisture, nutrients,
  sunlight and growing space to the seedlings.
• Weeds reduce crop growth, quality and yield. They
  make uprooting and transplanting difficult. Weeds
  also act as alternative hosts to pests and
  diseases affecting nursery seedlings.
• Weeds are difficult to mange as they grow and
  produce enormous and hardy reproductive
  structures like seeds.
• Integrated, combined and coordinated effort
  should be made in order to manage weeds in a
  nursery. Weed control involves cultural,
  mechanical and chemical methods of reducing
  weeds.

2
Effect of Weeds on Nursery

• Weed population reduce crop yield by competing
  for water, light, soil nutrients, and space. The
  combined effects of weeds are
• Reduced seedling quality by contamination of
  weeds in nursery.
• Interference during uprooting and transplantation
  of seedlings.
• Serve as hosts for various crop pest and
  diseases.
• Production of chemical substances which are toxic
  to nursery plants.

3
Characteristics of Nursery Weeds

• Specific characteristics of weeds make them hardy
  and helps their long survival under unfavorable
  conditions
• Genetic ability to produce abundant seed s and
  propagating units.
• Long term seed dormancy, long term seed survival
  and wide spread distribution and establishing
  ability.
• Adaptation in wide ecological and climatic
  conditions for survival in unfavorable growing
  conditions.
• There are nearly 300000 plant species on the
  earth, out of which nearly 3 plants (9000
  plants species) acts as weeds.

4
Weed Management in Tomato Nursery

• Tomato seedlings require regular and shallow
  hoeing during their initial days in the field.
  The surface soil is loosened by hand hoeing and
  weeds are removed by hand weeding.
• Mulching with straw or black polythene or many
  other materials found beneficial in managing
  weeds, diseases and improving the quality of
  seedlings produced.
• Proper preparation of land, sanitation,
  irrigation management, balanced plant nutrient
  supply and crop rotation practices can
  effectively reduce the weed population nursery.

5
Weeds in Tomato Nursery
Bermuda grass (Cynodon dactylon).
Branched broomrape, (Orobanche ramosa)
Young dodder Cuscuta spp.
Common groundsel, Senecio vulgaris.
Common purslane, Portulaca oleracea
6
Chemical Weed management in Tomato Nursery
Stages of Application Weedicide Dose Remarks
Preplanting surface application Alachlor Fluchloralin Metribuzin Nitrofen Oxadiazon 1.0-1.25 kg/ha 1.25 kg/ha 0.35 kg/ha 1.0 kg/ha 1.0 kg/ha Applied before sowing seeds on the nursery beds.
Pre emergence (in direct seeded crop) Alachlor Metribuzin Bensulide Diphenamid 1-2 kg/ha 0.2-0.35 kg/ha 4-6 kg/ha 4-6 kg/ha Should not be used in glass houses and high pH soils. Also do not tank- mix fertilizers with it.
Post emergence Metribuzin 0.28-0.5 kg/ha Apply when the crop is in 4-6 leaf stage
7
Precautions while using Weedicides

• Using chemical weedicides is a fast, effective,
  labor saving and cheaper method of managing weeds
  in the tomato nursery. However, weedicides must
  be used judiciously for profit maximization.
  Following points must be considered during
  weedicide use,
• Selection of proper weedicide based on
  application time and method.
• Doses and method of application of weedicides as
  per recommendations.
• Time and growth stages of crop considering
  environmental conditions before application.