PLANT-BASED PESTICIDES FOR CONTROL OF VEGETABLE PESTS

Compiled by:P. Kalama, M. Mulaa and T. Kwambai

For Further Information, Contact:Centre DirectorKALRO-Kitale

P.O. Box 450-30200 KitaleWireless 020-359161

Email: kalro.kitale@kalro.orghttp://www.kalro.org

Editorial and Publication Coordinated by:Knowledge, Information and Outreach Unit

KALRO Information Brochure Series No. 2017/018

Kshs. 30

Control: thrips, nematodes and leaf miners.

3.HOT CHILLI Chillies (Hot pepper)

• Chop 500 g ( 2cups) fresh fruits of chillies• Mix with 5 l. of water and leave for 24 hours

( or you may boil chillies in water for 20 minutes).

• Sieve the extract and add an extra 5 l. of water then add an equal amount of soapy water to make 20 l. of water enough to treat an acre

4.GARLICCan be intercropped with other vegetables such as kales and tomatoes. Acts as a repellant. Extracts can also be made using garlic.

Control: Leaf miners, white flies, aphids

Hot pepper fruits

Garlic bulb

Dwarf Mexican marigold

IntroductionBiopesticides (commonly referred to as Botanicals) are natural insecticides of plant origin. They include

• Pyrethrum, neem, tephrosia chilli, rotenone,rynia, sabadilla, tobacco

• Others that are referred to as repellantse.g. Garlic, magical marigold, pawpaw,Aloe vera.

Advantages of botanical pesticidesBotanical pesticides are not efficient as chemicals, but they have advantages such as:

• Made on or near farm with locally availableplant material

• Are cheaper to make.• Are generally much less harmful to pestpredators than chemical pesticides.

When to use Botanicals?• Botanicals are used effectively by farmers

who have good knowledge of the pestproblem: presence of pests, intensity ofdamage, numbers that warrant control.

• Preparation of some botanical pesticides• Prepare botanical pesticides by crushing

the leaves or fruit of selected plantsand soaking the substrate in water.The resultant mixture can be applied

Tephrosia plant

to the crops using either a sprayer or, if unavailable a twig broom.

Examples:

1.TEPHROSIA

One part crushed leaves of Tephrosia are mixed with 5 parts water and the mixture is blended with 500 g chilli that has been boiled and then left to cool. The cooled solution is finally mixed with 30 g soap (white) and is ready for use.

Control: Aphids and caterpillars.

2. MEXICAN MARIGOLDA common ornamental plant that is used as aplant repellant. The Mexican marigold rootsexude a substance that repels nematodes.

Mexican marigold and Tithonia preparation. • Cut Mexican marigold plant and tithonia at

flowering time, chop the plants to fill half 50 litre drum

• Add 20 litre of water, cover the drum onceevery 2 days to quicken decomposition

• Remove decomposed Mexican marigoldand tithonia particles 5-10 days later andsieve the extract

• Dilute the mixture with 10 litre of soapywater.

• The solution is enough to spray a 1/2 anacre

• Extracts of Mexican marigold and chilliescan be combined and sprayed to controlseveral pests

• The mixture is more active on various pestsmore than when each is used alone

• Mexican marigold can be planted aroundthe vegetable fields to repel various insectpests and nematodes which could damage the crop

• The decomposed material can be used asmulch in vegetable gardens