Role of Organic Farming In Insect Control

 Introduction:                                   

A method or sustainable technique for crop and livestock production which involves enhancement of natural fertility of land besides avoiding the use of synthetic pesticides, antibiotics, fertilizers, genetic engineering products and growth hormones. This is called organic farming. When we hear about organic farming, the very first question arises in our mind is that what is organic farming? Furthermore, how it is helping us to cope with pest control regarding to agricultural food commodities? So we should start our discussion with organic farming.

How to perform organically?

Performing organically involves 5 basic steps that are as follows:

1. Plan making for organic farming:

Take the crops of your interest and a crop with which you will do a rotation, what kind of natural fertilizers you would use in your farm and finally the techniques to avoid pests.

1. Prohibition of synthetic poisons:

Synthetic poisons are deterious for the health of both us people and our earth. Simply try to use following methods to get rid of your pest problem,

1. Prevention b)  Monitoring    c)  Control

• Rotation or Raise different crops:

A sequence of involving crops and cover crops to maintain or enhance the fertility of a particular field used to raise crop. Try to avoid conventional farming involving raising of a single crop on the same piece of land over years. This will eat up particular nutrients from that soil, soon the land will become devoid of those nutrients required by that particular crop and there will be stunted growth of that crop. Growing of different varieties of vegetables and crops with gradual turns will add up different minerals and essential nutrients into the soil thus enhancing the soil fertility.

1. Use of natural fertilizers:

Fertilize your land naturally as it would benefit a wide range of soil microorganisms (helping in different crucial land fertility procedures), beneficial insects, involving other factors incrementing in soil health.

Principles of organic farming:

1. Protection of soil environment, minimizing soil erosion and soil degradation, environmental balance, optimizing biological productivity and providing a sound soil health state.
2. Maintenance of biological diversity

• Recycling of resources and materials

1. Relying maximally on renewable resources
2. Careful processing and maintaining the organic integrity
3. Promotion of health and behavioral needs of livestock

(Canadian organic standards 2006)

Standards of organic farming:

Organic farming discourages the use of:

1. Synthetic chemicals(drugs, pesticides, food fertilizers )
2. Ionizing radiation

• Genetic engineering

The techniques and methods that are restricted to use must be avoided in certified organic farming lands. In livestock rearing the criterion is to feed animals 100% on organic feed and none other ingredients.

Certified organic:

A term used for the products grown in accordance to organic standards on a certified land certified through a certified body or organization.

Growth rate of organic agriculture:

Organic agriculture trend has become in since last 15 years. According to a survey it is most adapted in North America. According to the data of 2008 the retail organic market in America is $22.9 billion and in Canada it is $1.5 billion. Canada is particularly exporting soya bean and grains. 48% of organic farmland in Canada is devoted to soya bean and 40% to hay and pasture, 5% to vegetables and fruits.

1. Insects control by organic farming

Organic farming is the major tool to face the challenge of insect management as synthetic fertilizers, pesticides, fungicides, insecticides are banned in it. As insects are very well adaptive and greatly mobile to various farm production and insects control approaches.

3 pieces of information to control insects:

1. Biological perception:

Determining the needs of insects required to survive, insects-pests would automatically be controlled if they (insects) become devoid of these vital resources.

1. Ecological perception:

Determining the interactive behavior of insects with their environment so that we may establish an environment that would be pests resistant.

• Behavioral perception:

Collect information how insect pest gets its basic requirements or necessities and manipulates these conditions to control pests in order to protect your crop.

Plants defense against insects:

Plants avoid insects showing their defensive behavior which they have evolved like;

1. Morphologically specialized structures
2. Secondary plant metabolites

• Proteins with repellent, toxic and having anti nutritional effects on insects or herbivores.

Plants show 2 types of defense strategies:

1. Direct defense:

This involves straight effect on the biology of herbivores or insects. This defense is done by different toxic chemicals released by plants like terpenoids, cyanides, quinones, phenols, and alkaloids. Mechanical protection through hairs, trichomes, spines and thick leaves. Theses would retard or completely restrict insect’s development.

1. Indirect defense:

It is the way that is used by plants as a tactic to avoid insects. As, the plants release intentionally or unintentionally some chemicals that will attract the predators or parasitoids of the damaging insects. e.g: a caterpillar feeding on its host plant will unwittingly induces the plant to release such defensive compounds which will act as a signal to its (caterpillar) parasitoid wasp. In other words it is a way adapted by plants to avoid insects-pests by enhancing the chances of encounter of insect pest with its natural enemy. (Plant signal behavior- 2012 Oct 1: 7 (10): 1306-1320)

Cultural practices:

In any organic farm or agriculture growing one basic step is to focus on cultural practices that would inhibit or restrict pest species and natural enemies. This would involve:

1. Pheromones trap:

Certain chemicals used by organic farmers to entrap pests in order to disrupt their reproductive cycle.

1. Use of pathogens:

Disease causing agents in insects pests keep them under threshold. Overall this is way to control insects pest by pathogens thus is called microbial control.

• Use of natural enemies:

Use of insect’s parasites and parasitoids is an organic tool to control insect pests.

1. Monitoring the field regularly:

It is the fundamental management tool in any organic field. Visualize the infestation or attack according to a schedule. It is not some kind of hard or laborious procedure, it just should be done at regular intervals e.g. aphids and mites just need a direct observation. Other pests need just a simple sweep net to make an observation or data.

1. Crop cultivar:

Crop species provide a number of growth habits, resource opportunities and formats.

1. Plantation date and techniques:

If grow crops after spring when insects are in their most voracious feeding forms we can provide them with no or very less number of plants to feed on, this would protect our crops. As this is observed mostly in thrips that attack mostly on young plants. Sweet corn planted in early days is susceptible to less damage by corn earworm. A farmer should sow seed when conditions like temperature is allowing them to grow quickly so that they may encounter a little time with insects pests as much as possible but without effecting plant yield. Use of transplants and seedlings will help us achieve this aim.

• Crop rotation:

Providing the insects with least probability by circulating crops. e.g. wheat and gram.

• Avoiding host plants:

Avoid host plant growing near your major crop as it provides a place for the pests. e.g. avoid growing okra near cotton.

1. Harvesting date:

Don’t let your crop to stay in the field more than the required time. Prolonged presence of crop in the field the more are the chances of insects attack e.g. cucurbit will face less viral problems if early harvested.

1. Increment in soil organic contents:

Research have proven that soil with more organic matter will encourage microscopic life and mean while will increase insects predators. Natural compost that has been well treated is the best way.

1. Water management:

Irrigation is the only factor imparting both direct as well as indirect effect on insects. Try to raise humidity at micro level for microorganisms that are insect’s disease causing bacteria and fungi. Use different irrigation techniques like drip irrigation or sprinkle or flood irrigation.

3. Organic pest management:

IPM techniques are most effective in organic agriculture system as other synthetic chemicals are strictly prohibited. System of organic pest management gives us very basic ideas to farm organically as:

1. Sow a crop with chances of least pest attack
2. Selection of proper planting time

• Crop rotation

1. Proper crop positioning with regard to different nearby crops
2. Sanitation
3. Destruction of old crop residues

• Before plantation complete eradication of weeds
• Control over weeds when crop is in field

This would control crickets, vegetable weevils, cutworms, slugs, spider mites.

1. Mechanical weed control will control overwintered insects, i.e. fire ants mounds.
2. Beware of any damage to useful insects
3. Use trap crops e.g. sunflowers use leaf footed bugs from tomatoes

• Greenhouse
• Rely on biological control i.e. usage of pathogens, predators, parasites and parasitoids
• Mating disruption techniques

There are four ways to control pests other than pesticides:

1. Avoiding the pests
2. Modifying the climate

• Disrupting the life cycle of the pest

1. Fostering beneficial organisms

 written by. 

Amen Abbas, Farah Farooq, Dr. Muhammad Anjum Aqueel

Department of Entomology, University College of Agriculture, University of Sargodha, Pakistan