By Esther Mwoloi
In the previous publication we had identified some of the problems that farmers are likely to encounter in the farm during the rainy season. Farmers growing common crops such as maize, beans and green grams are likely to battle with fall army worm, stem borers and aphids. Ms Njeri Kinuthia, a seasoned extension officer, who has worked with farmers in various parts of the country for over 30 years, provides ecologically sustainable solutions by giving a step by step guide to making plant extracts that manage these stubborn pests.
Stem borers
Stem borers are insects which burrow in the stem of maize or sorghum. They can also be found in maize cobs of young plants. This burrowing and eating of the inside of the plant severely reduces the yield of maize and sorghum.
Aphids
They are small supping insects and members of the Aphidoidea family. Aphids are among the most destructive insect pests on cultivated plants in temperate regions. In addition to weakening the plant by sucking sap, they act as vectors for plant viruses and disfigure ornamental plants with deposits of honeydew and the subsequent growth of sooty moulds.
Fall armyworm
Fall armyworm is a species in the order Lepidoptera and is the larval life stage of a fall armyworm moth. It attacks lots of crop varieties but damages the maize crop to a larger extent and at all stages. In maize seedlings, it causes damage by feeding within the whorl. Larger larvae can cut the base of the plant while mature plants suffer attack on reproductive structures. Fall armyworm can be physically identified by spotting its egg masses, larvae, pupae or moths, or it can be identified by the damage caused by the larvae.
How to make a concoction to control stem borers , fall armyworm and aphids
Ingredients
1.4kg’s of Mexican Marigold
2.4kg’s of Tithonia leaves
3.4kg’s of black jack leaves
4. 4kg’s of stinging nettle leaves
5. 4kg’s of any legume leaves
6. 5 cloves of garlic
7.1 liter of Effective Microorganism (microbes) (EM1)
8. 1 liter of molasses
9. Ikg of chilies
Procedure
Mix EM 1 in a container and mix well.
Then add 20 litres of water and gradually all the other ingredients one at a time.
Let the mixture stand for 7-14 days in a dark room.
Keep on stirring the mixture once per day
Sieve the mixture to remove residues.
When applying dilute 1 litre mixture to: 2 liters of water and spray to young maize plant funnels immediately after germination.
You can alternatively use wood ash and sprinkle it into the maize funnel. This method makes the stem borer to suffocate due to the lack of oxygen and wearing out of the worm’s skin due to ash effects.
How to prepare microbes
Ingredients.
- 1kg of bean flour
- 1kg of fresh cow dung
- 1 liter of fresh cow urine
- 6 overripe bananas or 1kg of sugar
- 1kg of Neem, Tithonia or Lantana Camara leaves
- 10 litres of water
Procedure
- Add each ingredient gradually to 10 litres of water and stir both clockwise and anti clockwise for the mixture to get well mixed.
- Stirring should be done once for the rest of 10 days ( clockwise and anticlockwise)
- Cover the mixture in an air tight container for 10days.
- Mix the mixture into a ratio of 20ml of the concoction to 20litres of water.
- Soak the seedling into the concoction before planting for 30min.
- When planting seeds coat them with the concoction and let them stay under the shade for 30 minutes before planting.
- You can also drench the concoction into the soil to kill harmful microorganisms.
The mixture can only last for a period of 6 months.
“Farmers should avoid using synthetic pesticides because they destroy the ecosystem by killing some beneficial pollinators like bees and other insects such as the lady bird and birds,” says Kinuthia.