ANNONA – Soursop (Annona muricata) , Custard apple (Annona reticulata) , Sweetsop (Annona squamosa).

General

More than 90 species of small tree and shrubs are known in the Annonaceae family. They occur mostly in Tropical america, but some are found also in Asia and Africa. Soursop and custard apple are widely distributed in Central America and the Carribbean, while the sweetsop is commenest in India and Southeast Asia. They do not require special conditions of soil or water, but thrive best in places where ther is a clear division between the rainy and the dry season, and generally prefer dry sites in wich to grow.

The effective ingredients are in the unripe fruit, and in the seeds , leaves and roots. The oil content of the seeds amounts to 42-45 %.

Effective range

Contat – and stomac poison

Insecticidal , larvicidal , repellent , antifeedant.

Target Insects

Aphids                               -  general

Brown rice plant hopper  - Nilaparvata lugens

Diamondback Moth          - Plutella xylostella

Chrysanthemum aphid     - Macrosiphoniella sanborni

Grasshopper                    -  general

Green bugs                       -  general

Green rice leaf hopper              -  nephotettix virescens

Potato aphid                     -  Macrosiphum euphorbiae

Red pumpkin beetle         -  Aulacophora foveicollis

Whitebacked rice plante hopper – sogatella furcifera

Annona has not proved effective against the

Saw-toothed grain beetle         Oryzephilus surinamensis

Trouver une photo de Sweetop (annona squamosa)

Observations

The toxic effect of Annona sets in slowly , 2-3 days should be allowed.

Laboratory trials have shown that by extracting annona seeds with ether or petroleum ether, the toxicity can be increased 50-100 times. But since laboratory methods are impractical in the field, other locally availabe and cheap solvents could be tried, like petrol or kerosene.

When pulverising the seeds of A. squamosa , care should be taken to ensure that the powder does not come in contact with the eyes as this causes great pain.

The custard apple is the most effective of annonas against insects.

Methods of Use

Relatively little information exists on the preparation and use of annona. Wide-ranging laboratory trials have demonstrated its higly effective insecticidal values. Experimentally-inclined farmers could contribute much needed information about widely distributed plant.

         A 10 % concentration of seed oil produces a 90 % death rate of the bug Urnetius echinus within 72 hours. A 5-7 % concentration is still effective, but low concentration of 1 – 3 % produce no results.

         Pulverised seeds are used in China and the Philippines against Lecanium in West Africa. The writers gives no details regarding quantities.

         An extract of the leaves with ether proves higly successful against the red pumpkinn beetle (Aulacophora foveicollis). A diluted solution achieves a 91 % rate .