THE EFFECT OF LEVELS OF GREEN ANT, OECOPHYLLA SMARAGDINA (F.), COLONISATION ON CASHEW YIELD IN NORTHERN AUSTRALIA

摘要

Field surveys and experiments over a period of four years showed that trees fully occupied by green ants produced higher yields than trees with low presence of the ants or without the ants. Yield was positively correlated with levels of ant colonisation; 83 - 90% of the total variation in yield was explained. After stopping the use of insecticides, the ant colonisation level increased from 0 to 80% for first 2 or 3 years, and then the level oscillated under 80%. With isolation of colonies, 100% colonisation level can be achieved. The use of green ants in other tropical crops is discussed.