Natural crop protection
in the Tropics

by Gaby Stroll , 1986 , Copyright Margraf Publishers Scientific Books

TOBACCO – Nicotiana tabacum, N. rustica, N. glutinosa

General

Tobacco is a native of South America, but today it is grown all over the world, and its cultivation is successful under many ecological conditions. It does not succeed on water- logged soils ane on soils with high salt content . It thrives in warm situations and needs sufficient rain during the youth stage (47, 131).

Leaves and stalks are the plant parts used in crop protection. The highest concentration of nicotine is present in the stalkes and leaf ribs.

Effective Range

Contact-, stomach- and respiratory poison.

Insectcidal, repellent, fungicidal, acaricidal.

Espace pour photo  de tobacco (nicotiana tabacum)

Remarks

*Nicotine is one of the most toxic organic poisons. The nicotine of half a cigarette is sufficient to kill a fully-grown adult human. Therefore it is crucial to avoid any contact with the spray during the application. After the treatment, food plants are  not to be eaten for 3-4 days. This time is required for the nicotine (toxic to warm-blooded mammals) to decompose (35).

*Tobacco sprays are more effective when they are used at temperatures above 30°C (84).

Target Organisms

Aphids                          - general                       (52)

Cabbage orms            - general                       (52)

Caterpillars                   - general                       (35)

Flea beetles                 - general                       (52)

Grain weevils               - general

Leaf miners                  - general                       (35)

Mites                   - general                       (52)

Stem borers                 - general                       (52)

Thrips                           - general                       (35)

Rust in beans and wheat                                  (6)

« Kasahui », fungus disease of potatoes                 (60)

Methods of Use

*A spray can be prepared by soaking 1 kg of bru   tobacco

stalksand leaves in 15 litrs of water for one day. A small hand ful of soap flakes is added as adhesive agent. After one day the plant parts are filtered out. The sprays is applied immediately ith a sprayer, using a very   nozzle. All utensils should be thoroughly cleansed after use.

*250 gof tobacco, 30 gm liquid soap, 4 litres of water. The mixture is simmered for 30 minutes. Then it is diluted at 1 part tobacco  decoction : 4 parts water. The effect   increased when a little slaked lime is added. This solution controls insects like caterpillars, beetles, stem borers, leaf miners, aphids, thrips and creatures which pass some stage of their life cycle in the soil like cutworms. It does not affect lady birds and their larvae or hoverflies (35).

*In China rice is protected against sterm borers by immersing tobacco stalks in the roughly 5 cm deep water of the paddy fieds. 150-300 kg of stalks are used per hectare. This treatment should be employed after the  harvest and lasts for about 2 weeks (53).

*The following tobacco solution was used successfully in the La Paz region of Bolivia against aphids and Kasahui, a fungus disease of potatoes (60) :

4 litres boiling water, ½ kg tobacco leaves, ½ kg tablesspoon quicklime and ½ tablespoon cactus juice (opuntia).

*Beans and weat which were treated with a spray prepared from tobacco ( N. glutinosa) containing 0,01 % activez compounds , weree almost completely protected against rust disease (6).

 

*As  a preventive measure against the leaf curl virus which is carried to green peppers by thrips, young plants in the seedbeds were dusted with tobacco powder before being planted out in the field ().

© Seed to seed - sept 2001