Collecting insects

How to collect insects?

• By hand
  • Provide plastic bags or boxes
  • Use an aspirator for collecting small insects
  • Use a water pan
  • Search all plant parts and near plants
    • Stem
    • Leaves
    • Flowers
    • Fruits
    • Roots
    • Soil
    • On weeds
• Sweep nets
  • Use them to catch flying insects
• Traps
  • Use sticky traps to discover small insects (pests, natural enemies, neutrals)
  • Pitfall trap to catch insects that walk on the ground
  • Light traps

Why collect insects?

• For identification
  • Know what is there: pests, natural enemies, neutrals.
• For insect zoo.
  • Study life cycles
  • Study behavior: feeding habits, parasitization, etc.
  • Set small experiments
• For preservation.
  • Make a reference collection

Insect identification

When we collect insects from the field there is a lot we want to learn about them:

Naming the insect:

• Don’t use scientific names when talking with farmers
• Use common names; preferably local names used by the farmers
• Invent names if needed

Recognizing the insect:

• Study the body parts:
  • Shape
  • Color
  • Function
• Use identification guides or manuals
  • Photos, drawings
• Know the life cycle
  • Egg
  • Larva or nymph
  • Pupa
  • Adult
• What is its function in the ecosystem?
  • Herbivore (is it a pest?)
  • Predator
  • Parasitoid
  • Neutral
• Study its behavior
  • Activities, movement, dispersal in the field
  • Searching behavior
  • Feeding behavior
  • Where do they hide or rest?
• Keep records
  • Make drawings
  • Keep specimens for reference
  • Note down what you learned
• Start experiments to learn more
  • Insect zoo
  • Field cages
  • Use of traps
• Training materials to study insects
  • Hand lenses
  • Plastic bags
  • Sweep nets
  • Aspirator
  • Insect zoo
  • Traps

Insect pest management

There are many methods to manage pests. For many farmers the most obvious method is chemical control with synthetic insecticides. But this is also the most dangerous and destructive method, causing health and environmental problems. Synthetic pesticides should be used only as a very last choice, when all other options have been tried first.

Insects can be managed by:

• Use of resistant or tolerant varieties
• Crop rotation
• Intercropping
• Botanical pesticides (e.g. neem)
• Bio-control agents: insect pathogens
  • Bacillus thuringiensis (Bt)
  • NPV
  • Steinernema
  • Beauveria
• Biological control
  • Predators
  • Parasitoids
• Trapping
  • For example yellow sticky traps
• Managing the micro-climate
  • Pruning
  • Thinning
  • Watering
  • Mulching
• Chemical control
  • Only to be used as a last option
  • Select the least toxic product available
  • Never use class Ia or Ib chemicals
  • Avoid organophosphates and carbamates
  • Don’t use chemicals that are known to cause cancer, or to disrupt the endocrine system
  • Before using any chemical, first collect information about it (e.g. www.pesticideinfo.org)
  • Use spot applications. Do not treat the entire filed, but only the parts where pests are causing problems. Keep other areas free of pesticide as a refuge for natural enemies.

Diseases

Recognizing and identification

• Use identification guides
• Photos
• Drawings
• Invite experienced persons to help

Disease outbreaks

• How does a disease arrive in the crop?
• How do diseases spread within a crop?

Relation to weather conditions

• Humidity
• Temperature
• Micro-climate in the crop

Resistance and tolerance

• Crop varieties
• Grow a healthy crop

Disease management

Although fungicides and bactericides are generally less toxic than insecticides, we have to try to reduce their use as much as possible. In IPM, other methods to manage diseases should be explored first:

Diseases can be managed by:

• Crop rotation
• Sanitation
• Antagonists
  • Trichoderma
• Healthy plants
  • Good seed, strong seedlings, seed treatment
  • Fertilizer management
  • Water management
• Varieties
  • Resistance
  • Tolerance
• Manage the micro climate
  • Humidity
  • Temperature
  • Pruning
  • Thinning
  • Mulching
• Fungicides / bactericides
  • Only to be used as a last option
  • Select the least toxic product available
  • Never use class Ia or Ib chemicals
  • Don’t use chemicals that are known to cause cancer, or to disrupt the endocrine system

Weed management

Weeds compete with the crop for water, nutrients, space and light. But weeds also provide shelter for natural enemies. Flowering weeds provide food for adult parasitoid wasps. When weed control is needed, always consider if it is necessary to remove all weeds. It may be useful to keep some pockets of weeds as a refuge or food for natural enemies.

Weeds can be controlled in various ways. In IPM, chemical control should only be used as a last option. Especially the use of non-selective herbicides should be avoided because they destroy bio-diversity.

Methods to manage weeds include:

• Mechanical control
• Use of cover crops
• Use of mulch
• Water management
• Chemical control
• Only to be used as a last option
• Avoid Paraquat, it is the most dangerous herbicide
• Select the least toxic product available

Natural enemies

Integrated Pest Management consists of strategies that conserve and augment natural enemies. In the Farmer Field School we learn to recognize natural enemies and to understand their role in the ecosystem. Every crop management decision we take is aimed at conserving natural enemies (e.g. avoid pesticides) and creating an environment in which they can survive and multiply.