Protection methods

In countries heavily affected by Phytophthora casici , its control is quite difficult. It necessarily involves the use of the maximum of measures and methods recommended below.

• During cultivation

When symptoms of this chromist  are observed, it is first necessary to manage the better irrigation , especially if it has been excessive. Affected plants in the nursery will be eliminated and destroyed. In the field, if only a few plants distributed in outbreaks are affected, we advise you to eliminate them or bury them in order to limit secondary contamination to the surrounding healthy plants as much as possible. Otherwise, should be harvested the fruits located in the affected area (s) quickly before they become infected. It is advisable not to work in wet crops, this situation favoring the spread of this fungus.

In addition, care should be taken not to transport and use in other healthy plots all materials and tools present in the infected plot without having previously washed and disinfected them.

It is also necessary to check the quality of your water irrigation , your supply source may have been polluted.

Several fungicides are used around the world to control the development of P. capsici , both in the nursery and in the field: in particular mefenoxam, dimethomorph, etc. It is advisable to alternate products with different modes of action because strains resistant to some of these fungicides have already been reported.

It should be remembered that this pathogen is rather rare on Cucurbitaceae in France and that no fungicide is approved for this use (general treatments e-phy ). In the nursery, an anti-damping-off fungicide can be used ( e-phy ).

• Next crop

Of course the measures described above will be implemented during the next culture.

In some countries seeds and plants are suspected of harboring and spreading P. capsici . It is recommended to use only seeds and healthy plants . Seeds should never be collected from diseased fruits and / or produced in infected plots.

The nurseries will be disinfected ( e-phy ). It will be the same for the substrate if you have any doubts, and for the material and tools used to produce the plants.

In the field , some authors advise cultivating Cucurbitaceae only in soils free from this chromist. Of crop rotations of at least 5 years is still advocated with particular cereals and grasses. They should not involve peppers, tomatoes, eggplants and of course Cucurbitaceae. Heavy and humid soils will not be retained or they will be drained. The soil of infected plots should be tilled last. Then, the tillage equipment will be washed, even disinfected, before moving to another plot.

In heavily infested plots, the soil can be disinfected ( e-phy ). We will have to destroy the weeds.

Let us add that it will be preferable to set up the plants on mounds, and to use cover plants and a mulching of the ground which would limit the contaminations and the dispersion of this chromist. In addition, we will promote localized irrigation, we will also avoid watering the plants too abundantly, and forming persistent puddles.

Careful monitoring of crops will make it possible to detect the first diseased plants, eliminate them as far as possible, and initiate chemical control if necessary.

are not reported Resistant varieties among Cucurbitaceae species susceptible to P. capsici .

* Chemical control : As the number of pesticides available for a given use is constantly changing, we advise you to always confirm your choice by consulting the e-phy site of the Ministry of Agriculture and Fisheries which is an online catalog of products phytopharmaceuticals and their uses, fertilizers and growing media approved in France. This also applies to all biological products based on microorganisms or natural substances.