The Cypress aphids in the South of France.

In the South of France, Cinara (Cupressobium) cupressi, the main Cypress aphid, has been studied during 6 years on a mixed hedgerow in which Cupressus sempervirens and C. arizonica had been planted alternatively. In the area, this monoecious aphid is anholcyclic and heavily attended by ants. Continuous observation of the trees and of the colonies allowed a description of the population dynamics and the characterization of the damages. The two cypress species are regularly attacked, but the aphid appears earlier, remains longer and is more abundant on C. sempervirens, than on C. arizonica. The distribution of the colonies among trees is contagious. Some trees or groups of trees are attacked more frequently and/or present colonies earlier, suggesting that the tight interaction with ants may induce hivernation and early attack in some places.

Aphid pests of strawberry crops and their parasitoids in France.

The pest status of aphids on strawberry crops has changed with time. They were mainly considered with respect to virus transmission. Now, they are rather considered as sap-feeders and honeydew producers. As such, low populations regulated by natural enemies can be tolerated and systematic use of insecticides avoided. A survey of the species present in the different areas of production has been undertaken during 1999 and 2000 in France. During this survey, well known species of the strawberry crops have been found, like Chaetosiphon fragaefolii, Aphis forbesi or Acyrthosiphon rogersii. Widely polyphagous species like Aphis gossypii, Aulacorthum solani, Myzus ascalonicus or Macrosiphum euphorbiae were also present quite often. Eventually, aphids of the Rosaceae, not considered before as important pests of the strawberries, like Rhodobium porosum, have also been found in many different areas. The biology of the different species and their natural enemies have to be taken into account with respect to integrated control of strawberry pests.