XI. DISEASE & PEST CONTROL

Not all insects are bad in the garden. Without butterflies and bees many flowers would not give seed or fruit. Earthworms break down soil, letting air and water through and helping bacteria to break down natural rubbish to feed plants. A thriving diverse garden with healthy soil will attract beneficial insects that will make themselves useful pollinating, cleaning up rotting debris, and eating harmful insect larvae. In fact, in a balanced mini-ecosystem, for every seven or eight good bugs, there will be only one harmful one. If we get rid of all the bad bugs in our garden, the good bugs have less to eat and have no reason to stay around to help.

In bio intensive agriculture we emphasize organic natural pest control. There are various types that are discussed in detail below.
1. Cultural controls
2. Physical controls
3. Biological controls
4. Organic pest deterrents

Cultural Controls:

These are regular farm operations designed to destroy pests that do not require the use of specialized equip­ment or extra skill. The operations make the environment less favorable for surviv­al, growth and reproduction of the pest species. Methods of cultural controls:
Time of planting. - For a pest that emerges early in the season, planting of most of the crop can be delayed so that most of the pest population starves before the plants are available. On the other hand, later emergence of a pest population can lead to early planting of the host.
Crop rotation. - This is the practice of alternating crops from one year to the next in a given field. This practice takes advantage of the fact that most pests are limited to feeding on one kind of crop.
Destruction of crop residues (sanitation). - Many pests complete part of their life cycle in the dead leaves, stems, or other plant residues that remain in the field after harves­ting. Raking and burning these materials may be effective in keeping pest populations to a minimum level where it cannot cause damage to the succeeding crop.

Physical Controls:

We introduce barriers to control insects from damaging crops. Examples:
1.Banding trees with tart-lime for crawling insects
2.Constructing a fence around the garden to keep predators away. Materials to do this include sticks, grass, old maize, and fertilizer sacks, old fishing nets, etc.
3.Netting crops
4.Bagging fruits against boring insects (melon flies)
5.Introduction of the attractants (Pheromone and color attractants)
6.Planting crops together with repellents (herbs-i.e.. French Marigolds)
7.Planting thorny plants like Sisal, around the garden

Biological Controls:

Enlisting the aid of nature can encourage natural insect control. Some sources are:
1.Children around the house –can chase animals away from the garden
2.Birds -remove bed insects from the garden
3.Toads, snakes and spiders -eat insects and other garden pests
4.Ladybugs -eat aphids, but they don't eat beneficial insects
5.Praying Mantis -eat harmful and beneficial insects, therefore they should only be used in emergencies
6.Organic Pesticides –deter harmful pests without harming beneficial insects and microorganisms

Organic Pest Deterrents:

THREE BASIC KINDS OF INSECTS AND HOW TO CONTROL THEM EASILY:
Joshua Machinge

KIND

CONTROLLING
Chewing or biting, soft bodied and hard bodied
Aromatic and distasteful sprays such as garlic, onion and pepper spray.
Sucking soft bodied

Soap solution sprays (not detergents)
Sucking, hard bodied

Hand picking

Garlic / Onion Tea Insect Repellent:
Mash 10 cloves of garlic or a medium onion.
Mix with 2 quarts/liters of water.
Let it sit. Strain.
Spray without diluting.
(Good against nematodes)

“The Bomb” Insecticide”:
Melt ½ bar of bar soap (not detergent) in 8 quarts/liters of water.
Spray.
For strong pests, add 2 teaspoons of salt and about 30 mashed cayenne peppers.

LIST OF ORGANIC PESTICIDES AND HOW TO PREPARE THEM
-Evans Javasson

The main purpose is to avoid the use of chemical products that kill not only pests but also beneficial organisms in the environment. Many chemical pesticides quickly affect human beings. Others have residual effects and can accumulate in the body causing diseases. Therefore there is still considerable use of various plants and traditional practices in controlling pests in the field. The use of plants and other local resources in pest control is not, then, a novel idea for Africa farmers. However difficulties can arise when trying to introduce “new” approaches.

Subsistence farmers will naturally be conservative towards suggestions that they attempt anything but the known and trusted methods. Hence, introduction of different means of pest control requires a careful program of demonstration and reinforcement. Care must be taken to ensure that the pest control solutions are prepared and applied in the recommended manner. Not following the procedures of preparation with these natural solutions will render the solution less effective and less convincing to farmers.

A good natural pesticide from plant origin should have the following characteristics:
1.EASILY AVAILABLE
The plant should be easy to raise and not compete for space or nutrients with food crops. Ideally, the plant should be perennial, and have a multi-purpose function.
2.SIMPLE TO PREPARE
The process of collecting plant matter and preparing the insecticide solution should not be too time-consuming or require too high technical input.
3.VISIBLY BENEFICIAL
Since organic solutions generally repulse, rather than kill, garden pests, their action is less impressive than that of synthetic pesticides.
Farmers may also be skeptical towards the use of retrogressive local solutions as opposed to modern imported factory solutions. Therefore education to farmers on the action of organic pesticides is necessary.
4.COST EFFECTIVE
Where synthetic insecticides are readily available at low cost, farmers will gravitate towards their use. The extra labor required for cultivation and preparation of organic pesticides must be weighed against the financial cost of synthetic solutions.
5.TOXIC ONLY TO TARGET SPECIES
Beneficial insects, like bees, and the environment in general, should not be adversely affected by use of organic solutions.

There are sixty seven local solutions to crop pest control but only few are mentioned here, which are easily
available in most farmers’ local environments.

1. Papaya
Leaves of papaya contain fungicidal properties. Diseases such as coffee rust, powdery mildew and rice brown leaf spot can be controlled with papaya leaf solutions.
a. To make a solution effective against aphids, bugs, caterpillars, cutworms, root knot nematodes, termites, coffee rust, powdery mildew and rice brown leaf spot, mix one kg. of finely crushed leaves per liter of water, filter and dilute the solution with soapy water at a ratio of 1:4 (soapy water = 100g. soap mixed with 25 liters of water). Add two teaspoons of paraffin to this mixture per five (2: 5) liters of solution before spraying
b. Spray or water the ground around plants against cut worms.

2. Tomato
a. Boil stems and leaves of tomato plant in water - one kg. of chopped leaves in two liters of water; allow to cool, filter and then spray the solution on plants: deters attack from caterpillars, black or green flies. Apply this spray every two days for butterflies of cabbage worm.
b. Pound two cups of tomato leaves and stems. Soak in one liter of water and let stand overnight; filter, add one half liter of water and spray on plants: good against aphids
c. Cover finely crushed tomato stems with hot water - one kg. of crushed tomato stems per four liters of water; let stand for five hours, filter and spray on cabbage: repels butterflies of cabbage worms and diamond black moths

3. Asthma Weed (Euphorbia Hirta)
Crush 1 kg of Asthma Weed plant, soak in one liter of water; filter and make a spray by adding two liters of water: effective against aphids, red spider mites, termites and most other insects; also some fungi and viruses in general

4. Garlic
Steep three finely crushed garlic bulbs for two days in liquid paraffin. Use a glass, not tin, container. Filter this solution, stir in a large spoonful of soap and dilute with ten liters of water. This solution is said to kill most insects.

5. Urine
Fermented urine from cattle can be used to prevent attack from various pests and diseases. Urine has been demonstrated as effective in protecting green beans, melons, cabbage, tomato, okra etc. from most pests. It can also prevent mosaic virus disease in chilies and tomato and leaf curl virus in red peppers.
Let the cow urine stand for two weeks in container exposed to sunlight.
Dilute with water at a ratio of 1: 1 before spraying at weekly intervals. Two or three applications should be enough to prevent mosaic viral disease.
Diluted with water at a ratio of 1: 6, fermented cow urine is said to control stalk borers.
Less concentrated solutions of one part human urine to four parts of water can prevent fungal diseases such as downy mildew and vine powdery mildew, etc.

6. Castor Oil Plant
The leaves and green fruits (seeds) can be used to produce a contact poison to crop pests. A plant with red stems is said to be more effective than those with green stems. Care must be taken in using the seeds as they are poisonous to humans, chickens, guinea fowl, and other birds.
a.To produce a spray effective against a wide range of insects, soak green leaves and seeds in water for one full day, filter this solution and spray on plants or target insects.
b.For a powder to dust on plants or insects, dry green seeds and leaves, crush; then powder.
c. Cutworms can be killed by a solution mixing four cups of crushed, shelled seed with two liters of water. Boil for ten minutes; add two teaspoons of paraffin and liquid soap for adhesion. Add more water to make ten liters. Apply this solution immediately to the soil.
d. To kill fungal diseases, mix seeds, leaves or oil cake with soil.
e. To keep termites away from plants, apply leaves and branches as mulching materials.
f. Seeds will repel rats
g. Application of cake from the castor oil plant to field, at a rate of 1800 kg/ha, can significantly reduce population of nematodes.

7. Baking Soda (sodium bi-carbonate)
Solution of Sodium bicarbonate can prevent or cure several plant diseases.
Prepare a spray by dissolving 100g. baking powder in one liter of water. Add soap, filter, and dilute with nine liters of water. Stronger solutions may be required to cure; plant leaves are not harmed by the treatment. Sodium bicarbonate solution has a long protective effect in the field.

8. Manure
Manure from chicken, goats, cows and sheep can be used to add soil fertility, protect tree saplings from attack foraging ruminants and protect garden plants from a variety of pests and diseases.
a. Mix 2-3 dried cow patches (1 shovelful of manure) with ten liters of water in a bucket and stir daily for fourteen days to ferment the solution. If the smell becomes too disagreeable, sprinkle clay or stone dust over the surface (will also add useful minerals to the solution). Dilute with water at a ratio of 1: 3 – 5 and spray on all green parts of vegetable and fruits. Sprayed on leaves of plants will deter attack from animals, aphids, birds, caterpillars, etc.
b. Mix a shaveful of fresh donkey manure in a bucket of water and allow this to sit overnight to make an effective spray.

9. Milk
Solution made from one liter of milk with nine liters of water can be effective in controlling spider mites, and killing caterpillars’ eggs on plants in the crucifer plants (family) as well as preventing fungal and virus plant diseases.
a. Spray every ten days; this will also help in preventing Mosaic Virus in tomatoes, tobacco, and sugar cane.
b. A weaker solution of one part milk to ten to fifteen parts of water applied every ten days can also be effective in controlling mites and plant diseases on a wide variety of plants.
c. To control mildew, make a spray with one heaping teaspoon of wood ash mixed with one liter of water. Allow to steep overnight, filter, then mix with one cup sour milk and dilute with three liters of water.

10.Sweet Potatoes and Cassava
Aphids and various fungal diseases including rice brown, leaf spot and rice blast can be controlled with solution made from sweet potatoes leaves which have been crushed and mixed with water. Heavily starched water left after cooking sweet potatoes or cassava can be used also.

11.Neem
Neem is pre-eminent as a multi-purpose plant. Drought resistant and shade providing, the Neem tree has also earned a world-wide recognition for its many uses in medicines, soap making, and pest control. The Neem tree comes closest to best fulfilling the condition for a good source of plant-derived insecticides acceptable to local farmers.
Neem plant can be used with four of its parts: plant leaves, plant seeds, kernel powder, and Neem cake
a. Plant leaves:
Crush one kg. of Neem leaves and soak in one liter of water.
Allow to stay fro twelve to twenty-four hours or even for a week because for longer it stays the better the solution achieved.
Add four liters of water with 30 grams of soap; stir well until the soap is dissolved.
Sieve and use at a ratio of 1:15.
b. Plant Seeds
Fresh Neem seeds can be used to make a solution which is effective to most crop pests.
Shred and crush two kgs. of Neem seeds (fruits) with little water; add one liter of water and allow this mixture to sit overnight. Sieve properly and add more water until you make the total amount of 15 liters: apply onto plants.
c. Plant Kernel
Collect the plant kernel by lightly pulverizing the seeds to separate the brown kernels from the husks. Crush the kernels and then dry the pulp in the sun. Mix Neem kernel-powder with sawdust or clay at a ratio of 1:1, and sprinkle on young plants. One kilogram of this powder is enough for 1500 to 2000 plants but must be repeated after each rain.
d. Neem Cake: This is the solid remaining after the extraction of oil from the seeds.


12. Persian Lilac: This is a plant closely related to the Neem plant.
a.Leaf spray solution:
Mix 150 grams of fresh leaves or fifty grams of dried leaves in one liter of water.
Soak for twenty four hours.
Filter and spray on plants ratio 1: 20.
b.Leaves and fruits of Persian Lilac mixed with Mexican Marigold:
Soak Mexican Marigold along with leaves and fruits of Persian lilac in one liter of water for
a few days. Dilute the liquid obtained until the solution is pale-green or brown in color. Filter and spray.

13. Wood Ash
a. Apply wood ash directly around the stems of young seedlings after transplanting. It controls the cutworms from furrowing around the seedlings. It can control well if mixed with paraffin.
b. Mix wood ash and soapy water to make solution; two teaspoonfuls of ash with one liter of soapy water. Add five more liters of water. Filter and apply (spray) on plants. Or,
c. Mix one tablespoonful of wood ash with one liter of water and let the mixture stand overnight. Filter and add one cup of milk or buttermilk.
Dilute this again with water at a ratio of 1: 3.

14. Amaranthus Spp
Solution obtained from leaves and stems of this plant has a deterring effect on plant and fungus, especially against gray mold of fruits etc.
Crush one kg. of Amaranthus stems and leaves and soak in one liter of water.
Let stay overnight
Mix with thirty grams of soap, stir then add two more liters of water. Ratio 1: 10.

15. Annonas
Seeds are pounded into powder and mixed with water at a ratio of 1:10, meaning one kg. of powder in ten liters of water. Filter and then spray.
Caution: while preparing this solution avoid the powder getting into one’s eyes as this is very painful.

16. Lantana:
This plant has a contact poison against a wide range of insects.
Crush one handful of leaves per one liter of water.Add some soap, filter and apply as a spray on plants. Or, crush one kg. of leaves of lantana and add one liter of water. Let stand for 12 – 24 hours. Add four liters of water with thirty grams of soap. Stir well. Filter and spay on plants. Ratio 1: 15.

18. Lantang: Branches and leaves of Lantang control potato moth during storage. Lay the potatoes on fresh Lantang branches during storage.

19. Chilies Hot Peppers
Chop the fruit of chilies (500 gr. of fruits for 5 litters of water) boil the peppers for 20 minutes to make hot tea, sieve, and add equal amounts of beetles, cabbage worms and caterpillars.

17. Red Pepper:
Red pepper powder or liquid solution from, or mixed with, the ingredients is effective at killing or repelling many insects.
a.Mix ½ cup of crushed red pepper or ¼ cup of dried red pepper in two liters of water.
Let stand for twenty four hours, filter, add soap and spray.
b.Or crush or finely chop ½ cup of red pepper or ¼ cup dried red pepper mix with one cup of mint leaves and one cup of onion tops. Let stand for twenty four hours in one liter of water.
Filter and add ¼ cup of liquid soap, apply to plants.
c.Or boil half a kilo of chopped red pepper in three liters of water for 15-20 minutes.
Filter and add thirty grams of soap. Add an additional three more liters of water.
Stir well until soap is dissolved, then spray.
d.Or chop ripe peppers into small pieces- one hundred grams, about twelve large peppers.
Soak in one liter of water for twenty four hours.
Filter and add five liters of soapy water then spray.
e.Or mix two finely crushed garlic cloves with two teaspoonfuls of red pepper powder in four liters of hot soapy water. Stir well and spray.

18. Rubber Hedge:
Commonly used to make a living fence.
Chop few leaves of rubber hedge (Euphorbia) and add them to the planting holes to protect seedlings from termite attack.
To make a spray effective against most insects:
Mix rubber hedge sap with water at a ratio of 10 drops sap per one liter of water – the solution should appear a bit milky
Take care to avoid contact with the sap since it is poisonous- do not spray on windy days

19. Thorn Apple:
This plant has anti-feedant and insecticidal properties to general, and some fungal, diseases.
Dry the entire plant and crush into a powder for use as a dust.
Or crush a handful of leaves and mix with one liter of soapy water to use as a spray solution.

20. Tobacco:
When kiraiko tobacco or filters of cigarette ends are boiled in water, they control maize stalks, cutworms, ticks, aphids, cabbage, larvae, caterpillars, grain weevils and leaf miners.
Use 500 gm of tobacco in 8 litters of water
Boil and sieve after cooling.
Dilute with equal amount of water contain­ing 60 gm of bar soap to improve the effectiveness. NOTE: Tobacco is poisonous to man and animals; therefore, it must be kept away from children and domestic animals. It is recommended that crop harvesting be done 4-5 days after application.

21. Tephrosia (Fish Poison)
This plant is said to be effective for most crop pests. Some of the farmers use this plant as toxaphine to their animals.
Crush one kilo of fish poison leaves
Add one liter of water
Let the solution steep for 12-24 hours.
Add four more liters of water with 30 grams of soap. Stir well for soap to dissolve.
Sieve and spray at a ratio of 1:20.
Harvest should be delayed for 3-4 days after application of this solution.

22. Marigold:
This is a plant commonly used by most farmers to control nematodes in the soil. It is also used as one of pest repellants, and also against all fungi.
a. Crush 100-200 grams of marigold plant at flowering stage.
Soak in one liter of water (warm, preferably), for 24 hours or for 5-10 days.
Sieve and spray at a ratio of 1:1.
b. Or crush any amount of marigold which is dried
Apply the powder.
c. Or mix marigold plant with your soil while cultivating your land.

23. Bidens Pilosa:
This plant is said to be effective against most pests and other local people use it as a vegetable.
a. Use the seeds, one teacupful per one liter of water, and boil for 10 minutes.
Leave to stay for 24 hours.
Add another liter of water with 30 grams of soap and spray at a ratio of 2:15.
b. Use the whole Plant:
Crush the plant – one kg.
Soak in one liter of water overnight (12 hours)
Sieve and spray on plants at a ratio of 1:15.

24. Solanum Incumum (Sodom Apple)
Take 20-40 Solanum fruits and squeeze the juice from fruits. Add one liter of water. Leave to stay overnight. Add 30 grams of soap and additional two liters of water. Sieve carefully and spry at a ratio of 1:15.

25. Tithonia Diversifolia (Wild Sunflower)
This is a plant which is found in most parts and some people use it as a living hedge. It’s sometime grown beside the road.
a. Crush 100 grams of Tithonia.
Soak in one liter of water with 30 grams of soap.
Sieve and add more water until you get 15 liters then spray.
b. Ash from burned plant is also effective against termites and other insects.
c. The leaves of this plant can be used in compost making as it has a high nitrogen content.

26. Stinging Nettle:
Has a strengthening effect on the crop as it contains a good amount of iron.
Take 3 Kg of the leaves at flowering stage and place in a Debe full of water.
Let it stand for 5-10 days, stirring occasionally.
After sieving the residues can be used as mulches.
Dilute the solution with water contain­ing soap: effective on aphids, flies and caterpillars.

27. Onion or Garlic: Work as a repellant against many pests. They can be mixed with any one of the natural pesticides described above when applying in order to ensure the repellant effects.