Protection methods

- During cultivation

In France, the fight against bacterial infections of the salad is rather delicate because they often rage late which makes difficult the application of a chemical control *. However, a number of products, all copper-based, are available; sulphate copper, copper from copper hydroxide, copper from cuprous oxide, the fungal products of which fluctuate depending on whether it is an application on witloof chicory (chicory production) , witloof chicory (root production) or on escarole, curly . However, the use of bacteriostatic products such as copper is only relatively effective. In addition, it should be noted that strains of Pseudomonas cichorii resistant to copper and streptomycin have been reported on celery in Florida. In addition, it should be remembered that the salad is very sensitive to copper (risk of phytotoxicity). It is for this reason that the different forms that can be used are at doses lower than normal.

It seems obvious, knowing the biology of this bacterium, that it is necessary to avoid the irrigations by sprinkling when possible or to realize them rather in the morning than in the evening, so that the plants dry quickly during the day. This type of irrigation can be particularly dangerous near the harvest, especially if it is not well managed over time.

It is advisable not to work in the plots when the plants are wet; the risk of transmission of bacteria by contact is high.

The shelters will be well ventilated in order to dry the vegetation, in particular following irrigation by sprinkling. We will eliminate the maximum amount of plant debris at harvest and we will avoid burying them in the ground because the bacteria can stay there relatively well.


- Next crop

This bacteriosis represents a non-negligible risk for future cultures. Given the relative efficiency of copper, producers will have every interest in implementing prophylactic measures to reduce the establishment and spread of this bacterium.

The crop rotations , implemented preventively to delay the onset of telluric pathogens, will limit its retention in the soil. Indeed, rotations of three years, recommended for other crops, seem to give good results. Particular care should be taken in preparing the soil. be favored Good drainage of the latter will . And we will more readily use plots located in well-ventilated sites, favoring the drying of the leaf blade. The proximity of sensitive and / or already contaminated crops will be banned. Sensitive plants, especially weeds, should be removed.

We must not forget to remove or to disinfect all equipment (pots, stakes, string ...) used in the previous crop and that could come into contact with sick plants. For this, you can use bleach (titrating 12 ° chlorometric, soaking for 24 hours and rinsing with water) or formalin water (2 to 5% commercial formalin, soaking for 1 hour and storage under a 24-hour plastic film), or a commercial product * ( e-phy ) .

In production areas where it will be possible, we will choose to plant crops at a rather dry period of the year.

The manuring of the plants must be balanced , avoiding excess nitrogen. Culture conditions conducive to the appearance of be avoided "Tip burn" should .

The salads intended for the fourth line will be carefully harvested and quickly refrigerated. Batches of salad to be kept for a relatively long time or intended for the fourth range will be chosen from plots free from this bacteriosis.

In France, a copper-based antibacterial treatment is recommended on chicory, at the 8-10 leaf stage.

Differences in susceptibility to bacteriosis between types of salad and between cultivars are observed in the field. It does not seem that these differences in behavior were valued in selection. Indeed, there are currently no varieties of salad resistant to Pseudomonas cichorii .


* As the number of pesticides available for a given use is constantly changing, we have nevertheless chosen to indicate in each sheet the name of a few active ingredients approved at the time of writing. We will try to update this list, as withdrawals and new approvals occur. Despite this, 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 plant protection products and their uses, fertilizers and growing media. approved in France. This also applies to all biological products based on microorganisms or natural substances.