β-Aminobutyric acid induced phytotoxicity and effectiveness against nematode is stereomer-specific and dose-dependent in tomato.

β-Aminobutyric acid (BABA) induces resistance to a/biotic stress but is associated with phytotoxicity in some plant species. There are two enantiomers of BABA, the R and S enantiomers. We evaluated the phytotoxicity caused by the RS BABA (racemic mixture of R and S BABA), evaluating the dose-response effect and different modes of application on tomato.

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.

Weed control in rice with metham-sodium.

Metam-sodium is a soil fumigant with herbicidal properties. A field experiment was conducted in 2000 at Copiano (Pavia, Italy) to determine the efficacy of three rates of metam-sodium (300, 450 and 600 l/ha) at three different planting times (5, 12 and 18 days after chemical treatments) for the control of weeds in rice cultivation. The study mainly focused on the control of red rice (Oryza sativa var.

New urban trees/pests interactions in Europe.

The tree species have long been chosen for street use on the ground of the following criteria: they should be easy and inexpensive to produce, they had to be hardy and withstand stresses and finally they should not bear undesirable pests. Recently, in order to bypass pests and diseases problems that could have arisen, or simply to introduce aesthetic changes, more and more exotic tree species have been used. Some inappropriate practices were developed, for instance the transport of cuttings or of adult plants with soil, sometimes on long distances.

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.