PROSPECTS OF CONTROL OF PHYTOPHTHORA CACTORUM

Phytophthora cactorum, an extremely polyphagous cryptogamic agent may appear to be a dangerous parasite of the collar of the strawberry plant.
Such disease, mainly transmitted by young plants, is pernicious, since, most often, when a strawberry plant bears the parasite, no symptom is revealed.
Some external factors (hot and wet weather, strong luminous intensity, short photoperiod) and internal ones (beginning of the flowering, weak vegetative equilibrium) need to be present for the symptoms to appear.

Several reasons are put forward to explain why this disease is so widely spread in the South of France (propagation by young strawberry plants, choice of the varieties, generalization of the "frigo" plant technique).

Some prophylactic measures may be recommended both for the nurseries and the cultures in the open air (filtering soil, reduction of irrigations, cultures on hillock, shadowing of the plants, judicious choice of the planting-dates).

The production of sound plants is imperative for the control of Phytophthora cactorum.
The research undertaken by the I. N. R. A. and actively carried out by the Station of Pathology of Montfavet comprises:

• early detection of young plants contaminated with latent infection;

• regeneration of some strawberry plant clones by systematic cleansing and by the cultures of meristems;

• development of a rapid detection method of Phytophthora cactorum in the soil;

• behaviour of sound plant in a more or less contaminated soil.

Symposium on Strawberry under Protection

P.M. Molot

https://doi.org/10.17660/ActaHortic.1973.30.23