Querina (R) florina, apple variety resistant to apple scab. © INRA, LE LEZEC Marcel

Novel mechanisms for more sustainable resistance to disease

One avirulence precludes another (rapeseed)

Science has brought to light a negative interaction mechanism between two avirulence genes in phoma stem canker. In theory, this phenomenon renders the simultaneous presence of two corresponding resistance genes in the host plant futile.  However, if one of the two avirulence genes loses its avirulence - the corresponding rapeseed resistance gene no longer recognizing it – the other gene can then express its avirulence and the plant becomes resistant once again.

By Pascale Mollier, translated by Inge Laino
Updated on 03/31/2015
Published on 01/22/2015

Necrosis of rapeseed crown caused by phoma stem canker. © Marie-Hélène Balesdent and Thierry Rouxel, Marie-Hélène Balesdent et Thierry Rouxel
Necrosis of rapeseed crown caused by phoma stem canker © Marie-Hélène Balesdent and Thierry Rouxel, Marie-Hélène Balesdent et Thierry Rouxel

Combining several genes that are resistant to a given pathogen in a host plant is a common strategy for boosting the sustainability of resistance and delaying circumvention. It is indeed quite logical to expect that a pathogen will have a tougher time circumventing several, as opposed to one, sources of resistance.

However, there are cases where it is not as simple as that…

Researchers from five INRA teams have proven so with phoma stem canker in rapeseed (Leptosphaeria maculans). In this case, the combination of two resistance genes is futile, since only one expresses itself at a time. However, when one of the resistance genes is circumvented, the other can express itself efficiently to maintain resistance to phoma stem canker. In this atypical case, the question is: what is the best strategy for managing resistance and boosting sustainability?

Resistance and avirulence

A molecular dialogue takes place between a pathogen and its host plant that is often likened to an “arms race”. The pathogen has virulence determinants, called “effectors”, that the plant learns to recognise, and against which it develops targeted resistance thanks to an adaptive evolutionary mechanism. When an effector is thus “unmasked”, it triggers resistance against the pathogen in the plant. The gene that encodes this effector in the pathogen then becomes an avirulence gene, since the expression of the effector reduces the virulence of the pathogen.

In the case of phoma stem canker in rapeseed, several avirulence genes have been identified and cloned. Two of them were the subject of particularly close study, since they represent a rare case of negative interaction. That is, the expression of one hinders the effect of the other.

Negative interaction in avirulence genes

The avirulence genes AvrLm7 and AvrLm3 are present in natural populations of rapeseed phoma stem canker in France. These phoma genes correspond to two resistance genes in rapeseed called Rlm7 and Rlm3, respectively. When one of these two resistance genes is present in rapeseed, it recognises the effector encoded by the corresponding avirulence gene, triggering a resistance response in the plant against the pathogen.

However, scientists have observed that the expression of one avirulence gene inhibits the avirulence effect of the other. In other words, when Rlm7 is present in rapeseed, the resistance response is triggered against the effector encoded by AvrLm7, but at the same time, Rlm3 resistance is deactivated. That is, the effector encoded by AvrLm3 is no longer recognised by the Rlm3 product. The mechanism of this interaction is still unknown, but thought to be protein-based, whether between the two effectors or between effector and resistance proteins. Indeed, research has shown that the inhibition does not stem from avirulence gene expression.

This mechanism is logical from the “point of view” of the pathogen, since it leads to a weaking of avirulence.

“From the point of view of protecting plants, this antagonism between avirulence genes opens doors for managing resistance to phoma stem canker. Monogenetic Rlm7 resistance was progressively rolled out starting in 2004 in a number of rapeseed varieties in France, and reports of circumvention begin to appear in 2010-2011, with the emergence of virulent phoma strains vis-à-vis Rlm7. However, strains that circumvent Rlm7, that is, strains that are no longer Rlm7-avirulent, are avirulent for Rlm3, since the antagonism disappears. Resistance to Rlm3 can therefore be exploited to counter-select virulent strains vis-à-vis Rlm7, and therefore to boost the sustainability of Rlm7, while it was of no interest when Rlm7 was still effective”, concludes Marie-Hélène Balesdent, head of the K Masstec programme (1).

Researchers are now looking for the best way to combine resistance genes, simultaneously or progressively, by measuring and modelling the effect of different strategies on the frequency of virulent strains in pathogen populations. They are also striving to understand the molecular basis for this atypical interaction, thanks to the recent cloning of the AvrLm3 gene.

(1) K Masstec programme: Knowledge-driven design of management strategies for stem canker specific resistance genes.

Contact(s)
Scientific contact(s):

Associated Division(s):
Attribute Type Value
node_id string 101485
parent_node_id string 232
main_node_id string 101485
contentobject_id string 94947
contentobject_version string 45
contentobject_is_published string 1
depth string 3
sort_field string 1
sort_order string 1
priority string 1
modified_subnode string 1508318610
path_string string '/1/2/232/101485/'
path_identification_string string 'sitedept/deptunite211'
remote_id string '9fa85cadcebda2a03b8088bbec1d49a6'
is_hidden string 0
is_invisible string 0
name string 'Plant Health and Environment'
data_map array Array(33)
>seo object[eZContentObjectAttribute] Object
>title object[eZContentObjectAttribute] Object
>bloc_xml_introduction object[eZContentObjectAttribute] Object
>bloc_xml_presentation object[eZContentObjectAttribute] Object
>shortchapo object[eZContentObjectAttribute] Object
>zoom_news object[eZContentObjectAttribute] Object
>url object[eZContentObjectAttribute] Object
>mail_contact object[eZContentObjectAttribute] Object
>contact object[eZContentObjectAttribute] Object
>address object[eZContentObjectAttribute] Object
>robots object[eZContentObjectAttribute] Object
>metadescription object[eZContentObjectAttribute] Object
>centercode object[eZContentObjectAttribute] Object
>pathprefix object[eZContentObjectAttribute] Object
>display_twitterbar object[eZContentObjectAttribute] Object
>url_communitylink1 object[eZContentObjectAttribute] Object
>logo_communitylink1 object[eZContentObjectAttribute] Object
>url_communitylink2 object[eZContentObjectAttribute] Object
>logo_communitylink2 object[eZContentObjectAttribute] Object
>url_communitylink3 object[eZContentObjectAttribute] Object
>logo_communitylink3 object[eZContentObjectAttribute] Object
>url_communitylink4 object[eZContentObjectAttribute] Object
>logo_communitylink4 object[eZContentObjectAttribute] Object
>bloc_edito_intro object[eZContentObjectAttribute] Object
>bloc_edito_presentation object[eZContentObjectAttribute] Object
>jobdisplay object[eZContentObjectAttribute] Object
>visual object[eZContentObjectAttribute] Object
>credits object[eZContentObjectAttribute] Object
>mentions object[eZContentObjectAttribute] Object
>arborh object[eZContentObjectAttribute] Object
>extranet_link object[eZContentObjectAttribute] Object
>jobteaser object[eZContentObjectAttribute] Object
>urlteaser object[eZContentObjectAttribute] Object
object object[eZContentObject] Object
>id string 94947
>section_id string 1
>owner_id string 14
>contentclass_id string 50
>name string 'Plant Health and Environment'
>published string 1358171188
>modified string 1454592740
>current_version string 45
>status string 1
>remote_id string 'cd9e9b4178ddf7f7d69cd809e5a97b87'
>language_mask string 6
>initial_language_id string 2
>current object[eZContentObjectVersion] Object
>versions array Array(10)
>author_array array Array(3)
>class_name string 'Département : Site'
>content_class object[eZContentClass] Object
>contentobject_attributes array Array(33)
>owner object[eZContentObject] Object
>related_contentobject_array array Array(0)
>related_contentobject_count string 0
>reverse_related_contentobject_array array Array(0)
>reverse_related_contentobject_count string 1
>linked_contentobject_array array Array(0)
>linked_contentobject_count string 0
>reverse_linked_contentobject_array array Array(0)
>reverse_linked_contentobject_count string 1
>embedded_contentobject_array array Array(0)
>embedded_contentobject_count string 0
>reverse_embedded_contentobject_array array Array(0)
>reverse_embedded_contentobject_count string 0
>can_read boolean true
>can_pdf boolean true
>can_diff boolean false
>can_create boolean false
>can_create_class_list array Array(0)
>can_edit boolean false
>can_translate boolean false
>can_remove boolean false
>can_move boolean false
>can_move_from boolean false
>can_view_embed boolean false
>data_map array Array(33)
>grouped_data_map array Array(1)
>main_parent_node_id string 232
>assigned_nodes array Array(1)
>parent_nodes array Array(1)
>main_node_id string 101485
>main_node object[eZContentObjectTreeNode] Object
>default_language string 'eng-GB'
>content_action_list boolean false
>class_identifier string 'inra_departement'
>class_group_id_list array Array(1)
>match_ingroup_id_list boolean false
>current_language string 'eng-GB'
>current_language_object object[eZContentLanguage] Object
>initial_language object[eZContentLanguage] Object
>initial_language_code string 'fre-FR'
>available_languages array Array(1)
>language_codes array Array(1)
>language_js_array string '[{"locale":"eng-GB","name":"English (United Kingdom)"}]'
>languages array Array(1)
>all_languages array Array(2)
>can_edit_languages array Array(0)
>can_create_languages array Array(0)
>always_available integer 0
>allowed_assign_section_list array Array(1)
>allowed_assign_state_id_list array Array(1)
>allowed_assign_state_list array Array(0)
>state_id_array array Array(1)
>state_identifier_array array Array(1)
subtree array Array(45)
>0 object[eZContentObjectTreeNode] Object
>1 object[eZContentObjectTreeNode] Object
>2 object[eZContentObjectTreeNode] Object
>3 object[eZContentObjectTreeNode] Object
>4 object[eZContentObjectTreeNode] Object
>5 object[eZContentObjectTreeNode] Object
>6 object[eZContentObjectTreeNode] Object
>7 object[eZContentObjectTreeNode] Object
>8 object[eZContentObjectTreeNode] Object
>9 object[eZContentObjectTreeNode] Object
>10 object[eZContentObjectTreeNode] Object
>11 object[eZContentObjectTreeNode] Object
>12 object[eZContentObjectTreeNode] Object
>13 object[eZContentObjectTreeNode] Object
>14 object[eZContentObjectTreeNode] Object
>15 object[eZContentObjectTreeNode] Object
>16 object[eZContentObjectTreeNode] Object
>17 object[eZContentObjectTreeNode] Object
>18 object[eZContentObjectTreeNode] Object
>19 object[eZContentObjectTreeNode] Object
>20 object[eZContentObjectTreeNode] Object
>21 object[eZContentObjectTreeNode] Object
>22 object[eZContentObjectTreeNode] Object
>23 object[eZContentObjectTreeNode] Object
>24 object[eZContentObjectTreeNode] Object
>25 object[eZContentObjectTreeNode] Object
>26 object[eZContentObjectTreeNode] Object
>27 object[eZContentObjectTreeNode] Object
>28 object[eZContentObjectTreeNode] Object
>29 object[eZContentObjectTreeNode] Object
>30 object[eZContentObjectTreeNode] Object
>31 object[eZContentObjectTreeNode] Object
>32 object[eZContentObjectTreeNode] Object
>33 object[eZContentObjectTreeNode] Object
>34 object[eZContentObjectTreeNode] Object
>35 object[eZContentObjectTreeNode] Object
>36 object[eZContentObjectTreeNode] Object
>37 object[eZContentObjectTreeNode] Object
>38 object[eZContentObjectTreeNode] Object
>39 object[eZContentObjectTreeNode] Object
>40 object[eZContentObjectTreeNode] Object
>41 object[eZContentObjectTreeNode] Object
>42 object[eZContentObjectTreeNode] Object
>43 object[eZContentObjectTreeNode] Object
>44 object[eZContentObjectTreeNode] Object
children array Array(8)
>0 object[eZContentObjectTreeNode] Object
>1 object[eZContentObjectTreeNode] Object
>2 object[eZContentObjectTreeNode] Object
>3 object[eZContentObjectTreeNode] Object
>4 object[eZContentObjectTreeNode] Object
>5 object[eZContentObjectTreeNode] Object
>6 object[eZContentObjectTreeNode] Object
>7 object[eZContentObjectTreeNode] Object
children_count string 8
view_count integer 0
contentobject_version_object object[eZContentObjectVersion] Object
>id string 346085
>contentobject_id string 94947
>creator_id string 95411
>version string 45
>status string 1
>created string 1454592692
>modified string 1454592738
>workflow_event_pos string 0
>user_id string 0
>language_mask string 7
>initial_language_id string 4
>creator object[eZContentObject] Object
>name string 'Santé des plantes et environnement'
>version_name string 'Plant Health and Environment'
>main_parent_node_id string 232
>contentobject_attributes array Array(33)
>related_contentobject_array array Array(0)
>reverse_related_object_list array Array(0)
>parent_nodes array Array(1)
>can_read boolean false
>can_remove boolean false
>data_map array Array(33)
>node_assignments array Array(1)
>contentobject object[eZContentObject] Object
>initial_language object[eZContentLanguage] Object
>language_list array Array(2)
>translation boolean false
>translation_list array Array(2)
>complete_translation_list array Array(2)
>temp_main_node object[eZContentObjectTreeNode] Object
sort_array array Array(1)
>0 array Array(2)
can_read boolean true
can_pdf boolean true
can_create boolean false
can_edit boolean false
can_hide boolean false
can_remove boolean false
can_move boolean false
can_move_from boolean false
can_add_location boolean false
can_remove_location boolean false
can_view_embed boolean false
is_main boolean true
creator object[eZContentObject] Object
>id string 95411
>section_id string 2
>owner_id string 14
>contentclass_id string 4
>name string 'Ridel Arnaud'
>published string 1358178891
>modified string 1472277907
>current_version string 2
>status string 1
>remote_id string '3de74e62d7f07c022184d4cf3b497c92'
>language_mask string 3
>initial_language_id string 2
>current object[eZContentObjectVersion] Object
>versions array Array(2)
>author_array array Array(2)
>class_name string 'User'
>content_class object[eZContentClass] Object
>contentobject_attributes array Array(5)
>owner object[eZContentObject] Object
>related_contentobject_array array Array(0)
>related_contentobject_count string 0
>reverse_related_contentobject_array array Array(0)
>reverse_related_contentobject_count string 0
>linked_contentobject_array array Array(0)
>linked_contentobject_count string 0
>reverse_linked_contentobject_array array Array(0)
>reverse_linked_contentobject_count string 0
>embedded_contentobject_array array Array(0)
>embedded_contentobject_count string 0
>reverse_embedded_contentobject_array array Array(0)
>reverse_embedded_contentobject_count string 0
>can_read boolean false
>can_pdf boolean false
>can_diff boolean false
>can_create boolean false
>can_create_class_list array Array(0)
>can_edit boolean false
>can_translate boolean false
>can_remove boolean false
>can_move boolean false
>can_move_from boolean false
>can_view_embed boolean false
>data_map array Array(5)
>grouped_data_map array Array(1)
>main_parent_node_id string 312
>assigned_nodes array Array(4)
>parent_nodes array Array(4)
>main_node_id string 101969
>main_node object[eZContentObjectTreeNode] Object
>default_language string 'eng-GB'
>content_action_list boolean false
>class_identifier string 'user'
>class_group_id_list array Array(1)
>match_ingroup_id_list boolean false
>current_language string 'fre-FR'
>current_language_object object[eZContentLanguage] Object
>initial_language object[eZContentLanguage] Object
>initial_language_code string 'fre-FR'
>available_languages array Array(0)
>language_codes array Array(0)
>language_js_array boolean false
>languages array Array(0)
>all_languages array Array(1)
>can_edit_languages array Array(0)
>can_create_languages array Array(0)
>always_available integer 1
>allowed_assign_section_list array Array(1)
>allowed_assign_state_id_list array Array(1)
>allowed_assign_state_list array Array(0)
>state_id_array array Array(1)
>state_identifier_array array Array(1)
path_with_names string 'sitedept/deptunite211'
path array Array(2)
>0 object[eZContentObjectTreeNode] Object
>1 object[eZContentObjectTreeNode] Object
path_array array Array(4)
>0 integer 1
>1 integer 2
>2 integer 232
>3 integer 101485
parent object[eZContentObjectTreeNode] Object
>node_id string 232
>parent_node_id string 2
>main_node_id string 232
>contentobject_id string 219
>contentobject_version string 61
>contentobject_is_published string 1
>depth string 2
>sort_field string 9
>sort_order string 1
>priority string 2
>modified_subnode string 1508779906
>path_string string '/1/2/232/'
>path_identification_string string 'sitedept'
>remote_id string '702cee6c5bb3a0f2459eb4705cbf71aa'
>is_hidden string 0
>is_invisible string 0
>name string 'INRA Divisions'
>data_map array Array(23)
>object object[eZContentObject] Object
>subtree array Array(827)
>children array Array(17)
>children_count string 17
>view_count integer 0
>contentobject_version_object object[eZContentObjectVersion] Object
>sort_array array Array(1)
>can_read boolean true
>can_pdf boolean true
>can_create boolean false
>can_edit boolean false
>can_hide boolean false
>can_remove boolean false
>can_move boolean false
>can_move_from boolean false
>can_add_location boolean false
>can_remove_location boolean false
>can_view_embed boolean false
>is_main boolean true
>creator object[eZContentObject] Object
>path_with_names string 'sitedept'
>path array Array(1)
>path_array array Array(3)
>parent object[eZContentObjectTreeNode] Object
>url string 'sitedept'
>url_alias string 'sitedept'
>class_identifier string 'inra_site_departements'
>class_name string 'Départements : Dispatch'
>hidden_invisible_string string '-/-'
>hidden_status_string string 'Visible'
>classes_js_array string '[{"classID":57,"name":"Actualit\u00e9"},{"classID":131,"name":"Annuaire : Rubrique"},{"classID":16,"name":"Article"},{"classID":17,"name":"Article (main-page)"},{"classID":18,"name":"Article (sub-page)"},{"classID":42,"name":"Banner"},{"classID":19,"name":"Blog"},{"classID":81,"name":"Blog : Billet"},{"classID":101,"name":"Blog : Billet marque blanche"},{"classID":62,"name":"Blog : Blog"},{"classID":99,"name":"Blog : Blog marque blanche"},{"classID":82,"name":"Blog : Rubrique additionnelle"},{"classID":20,"name":"Blog post"},{"classID":127,"name":"Br\u00e8ve"},{"classID":60,"name":"Carrousel : Actu de carrousel"},{"classID":143,"name":"Carrousel : Diapositive autonome"},{"classID":168,"name":"Carrousels"},{"classID":56,"name":"Centre : Site"},{"classID":94,"name":"Centres : Dispatch"},{"classID":13,"name":"Comment"},{"classID":50,"name":"D\u00e9partement : Site"},{"classID":95,"name":"D\u00e9partements : Dispatch"},{"classID":71,"name":"Digital Asset (Media)"},{"classID":24,"name":"Documentation page"},{"classID":154,"name":"Dossier"},{"classID":116,"name":"Dossier 'Parutions'"},{"classID":76,"name":"Dossier 'Quizs'"},{"classID":169,"name":"Dossier actu secondaire"},{"classID":89,"name":"Ev\u00e9nement"},{"classID":88,"name":"Ev\u00e9nements : Racine"},{"classID":40,"name":"Event"},{"classID":41,"name":"Event calendar"},{"classID":22,"name":"Feedback form"},{"classID":28,"name":"File"},{"classID":29,"name":"Flash"},{"classID":1,"name":"Folder"},{"classID":37,"name":"Forum"},{"classID":39,"name":"Forum reply"},{"classID":38,"name":"Forum topic"},{"classID":43,"name":"Forums"},{"classID":23,"name":"Frontpage"},{"classID":35,"name":"Gallery"},{"classID":36,"name":"Geo Article"},{"classID":145,"name":"Glossaire : Mot"},{"classID":30,"name":"Image"},{"classID":25,"name":"Infobox"},{"classID":130,"name":"Instit : Fiche Annuaire"},{"classID":140,"name":"Instit : Nous trouver"},{"classID":48,"name":"Instit : Racine"},{"classID":133,"name":"Instit : Rubrique 'Actu'"},{"classID":139,"name":"Instit : Th\u00e8me 'Annuaire'"},{"classID":134,"name":"Instit : Th\u00e8me 'Missions'"},{"classID":137,"name":"Instit : Th\u00e8me 'Organisation'"},{"classID":135,"name":"Instit : Th\u00e8me 'Rep\u00e8res'"},{"classID":136,"name":"Instit : Th\u00e8me 'Strat\u00e9gie'"},{"classID":46,"name":"Kiosque : Racine"},{"classID":31,"name":"Link"},{"classID":201,"name":"Logo"},{"classID":72,"name":"Magazine"},{"classID":142,"name":"Mediath\u00e8que : Mot cl\u00e9"},{"classID":149,"name":"Mediath\u00e8que : Playlist"},{"classID":52,"name":"Mediath\u00e8que : Racine"},{"classID":150,"name":"Mediath\u00e8que : Rubrique 'Mots cl\u00e9s'"},{"classID":148,"name":"Mediath\u00e8que : Rubrique 'Playlist'"},{"classID":141,"name":"Mediath\u00e8que : Rubrique 'Zoom'"},{"classID":199,"name":"Mediath\u00e8que : Rubrique simple"},{"classID":121,"name":"M\u00e9taprogramme : Site"},{"classID":96,"name":"M\u00e9taprogrammes : Dispatch"},{"classID":161,"name":"Mon Compte"},{"classID":124,"name":"Mon Compte : Utilisateur Front"},{"classID":26,"name":"Multicalendar"},{"classID":119,"name":"Newsletter : Abonn\u00e9"},{"classID":104,"name":"Newsletter : Bloc s\u00e9l\u00e9ction"},{"classID":105,"name":"Newsletter : Bloc texte"},{"classID":103,"name":"Newsletter : Campagne simple"},{"classID":102,"name":"Newsletter : Campagne sp\u00e9ciale"},{"classID":120,"name":"Newsletter : Dossier 'Abonn\u00e9s'"},{"classID":122,"name":"Newsletter : Dossier 'D\u00e9sinscrits'"},{"classID":125,"name":"Newsletter : Dossier 'Entreprises'"},{"classID":126,"name":"Newsletter : Entreprise"},{"classID":100,"name":"Newsletter : Newsletter"},{"classID":92,"name":"Parution"},{"classID":27,"name":"Poll"},{"classID":47,"name":"Portail : Canal"},{"classID":45,"name":"Portail : Racine"},{"classID":53,"name":"Portail : Th\u00e8me"},{"classID":185,"name":"Portrait"},{"classID":163,"name":"Portrait Old"},{"classID":87,"name":"Presse : Accueil public"},{"classID":108,"name":"Presse : Biographie"},{"classID":91,"name":"Presse : Communiqu\u00e9"},{"classID":118,"name":"Presse : Dossier 'Biographies'"},{"classID":112,"name":"Presse : Dossier 'Communiqu\u00e9s'"},{"classID":115,"name":"Presse : Dossier 'Dossiers de presse'"},{"classID":203,"name":"Presse : Dossier 'Kits de presse'"},{"classID":107,"name":"Presse : Dossier de presse"},{"classID":63,"name":"Presse : Inscription"},{"classID":205,"name":"Presse : Kit de presse"},{"classID":51,"name":"Presse : Racine"},{"classID":21,"name":"Product"},{"classID":32,"name":"Quicktime"},{"classID":73,"name":"Quiz : Accueil"},{"classID":74,"name":"Quiz : Question"},{"classID":195,"name":"Quiz : question - r\u00e9ponse"},{"classID":75,"name":"Quiz : R\u00e9ponse"},{"classID":69,"name":"Racine"},{"classID":34,"name":"Real video"},{"classID":179,"name":"RH : Annonce permanente"},{"classID":176,"name":"RH : Annonce temporaire"},{"classID":181,"name":"RH : Article simple"},{"classID":172,"name":"RH : Campagne permanente"},{"classID":180,"name":"RH : Campagne temporaire"},{"classID":207,"name":"RH : Connexion Espagnole"},{"classID":187,"name":"RH : Discipline scientifique"},{"classID":193,"name":"RH : Domaine professionnel"},{"classID":165,"name":"RH : dossier 'Portraits'"},{"classID":177,"name":"RH : Dossier Reportages"},{"classID":183,"name":"RH : Fichier description"},{"classID":184,"name":"RH : Fichier inscription"},{"classID":178,"name":"RH : Folder annonces"},{"classID":197,"name":"RH : mobilit\u00e9 internationale"},{"classID":171,"name":"RH : Proc\u00e9dure"},{"classID":49,"name":"RH : Racine"},{"classID":175,"name":"RH : R\u00e9gion"},{"classID":167,"name":"RH : Rubrique"},{"classID":164,"name":"RH : Rubrique 'Actu'"},{"classID":170,"name":"RH : Rubrique emploi"},{"classID":174,"name":"RH : textes candidatures"},{"classID":189,"name":"RH : Type d'annonce"},{"classID":191,"name":"RH : Type nature de contrat"},{"classID":106,"name":"RSS : Flux"},{"classID":129,"name":"Rubrique texte simple"},{"classID":146,"name":"SEO : Robots txt"},{"classID":147,"name":"SEO : Sitemap xml"},{"classID":151,"name":"SEO : Valeurs par d\u00e9faut"},{"classID":44,"name":"Silverlight"},{"classID":166,"name":"Sites : Rubrique"},{"classID":33,"name":"Windows media"},{"classID":182,"name":"Xiti : Identifiants Home"}]'
>is_container string 1
url string 'sitedept/deptunite211'
url_alias string 'sitedept/deptunite211'
class_identifier string 'inra_departement'
class_name string 'Département : Site'
hidden_invisible_string string '-/-'
hidden_status_string string 'Visible'
classes_js_array string '[{"classID":57,"name":"Actualit\u00e9"},{"classID":131,"name":"Annuaire : Rubrique"},{"classID":16,"name":"Article"},{"classID":17,"name":"Article (main-page)"},{"classID":18,"name":"Article (sub-page)"},{"classID":42,"name":"Banner"},{"classID":19,"name":"Blog"},{"classID":81,"name":"Blog : Billet"},{"classID":101,"name":"Blog : Billet marque blanche"},{"classID":62,"name":"Blog : Blog"},{"classID":99,"name":"Blog : Blog marque blanche"},{"classID":82,"name":"Blog : Rubrique additionnelle"},{"classID":20,"name":"Blog post"},{"classID":127,"name":"Br\u00e8ve"},{"classID":60,"name":"Carrousel : Actu de carrousel"},{"classID":143,"name":"Carrousel : Diapositive autonome"},{"classID":168,"name":"Carrousels"},{"classID":56,"name":"Centre : Site"},{"classID":94,"name":"Centres : Dispatch"},{"classID":13,"name":"Comment"},{"classID":50,"name":"D\u00e9partement : Site"},{"classID":95,"name":"D\u00e9partements : Dispatch"},{"classID":71,"name":"Digital Asset (Media)"},{"classID":24,"name":"Documentation page"},{"classID":154,"name":"Dossier"},{"classID":116,"name":"Dossier 'Parutions'"},{"classID":76,"name":"Dossier 'Quizs'"},{"classID":169,"name":"Dossier actu secondaire"},{"classID":89,"name":"Ev\u00e9nement"},{"classID":88,"name":"Ev\u00e9nements : Racine"},{"classID":40,"name":"Event"},{"classID":41,"name":"Event calendar"},{"classID":22,"name":"Feedback form"},{"classID":28,"name":"File"},{"classID":29,"name":"Flash"},{"classID":1,"name":"Folder"},{"classID":37,"name":"Forum"},{"classID":39,"name":"Forum reply"},{"classID":38,"name":"Forum topic"},{"classID":43,"name":"Forums"},{"classID":23,"name":"Frontpage"},{"classID":35,"name":"Gallery"},{"classID":36,"name":"Geo Article"},{"classID":145,"name":"Glossaire : Mot"},{"classID":30,"name":"Image"},{"classID":25,"name":"Infobox"},{"classID":130,"name":"Instit : Fiche Annuaire"},{"classID":140,"name":"Instit : Nous trouver"},{"classID":48,"name":"Instit : Racine"},{"classID":133,"name":"Instit : Rubrique 'Actu'"},{"classID":139,"name":"Instit : Th\u00e8me 'Annuaire'"},{"classID":134,"name":"Instit : Th\u00e8me 'Missions'"},{"classID":137,"name":"Instit : Th\u00e8me 'Organisation'"},{"classID":135,"name":"Instit : Th\u00e8me 'Rep\u00e8res'"},{"classID":136,"name":"Instit : Th\u00e8me 'Strat\u00e9gie'"},{"classID":46,"name":"Kiosque : Racine"},{"classID":31,"name":"Link"},{"classID":201,"name":"Logo"},{"classID":72,"name":"Magazine"},{"classID":142,"name":"Mediath\u00e8que : Mot cl\u00e9"},{"classID":149,"name":"Mediath\u00e8que : Playlist"},{"classID":52,"name":"Mediath\u00e8que : Racine"},{"classID":150,"name":"Mediath\u00e8que : Rubrique 'Mots cl\u00e9s'"},{"classID":148,"name":"Mediath\u00e8que : Rubrique 'Playlist'"},{"classID":141,"name":"Mediath\u00e8que : Rubrique 'Zoom'"},{"classID":199,"name":"Mediath\u00e8que : Rubrique simple"},{"classID":121,"name":"M\u00e9taprogramme : Site"},{"classID":96,"name":"M\u00e9taprogrammes : Dispatch"},{"classID":161,"name":"Mon Compte"},{"classID":124,"name":"Mon Compte : Utilisateur Front"},{"classID":26,"name":"Multicalendar"},{"classID":119,"name":"Newsletter : Abonn\u00e9"},{"classID":104,"name":"Newsletter : Bloc s\u00e9l\u00e9ction"},{"classID":105,"name":"Newsletter : Bloc texte"},{"classID":103,"name":"Newsletter : Campagne simple"},{"classID":102,"name":"Newsletter : Campagne sp\u00e9ciale"},{"classID":120,"name":"Newsletter : Dossier 'Abonn\u00e9s'"},{"classID":122,"name":"Newsletter : Dossier 'D\u00e9sinscrits'"},{"classID":125,"name":"Newsletter : Dossier 'Entreprises'"},{"classID":126,"name":"Newsletter : Entreprise"},{"classID":100,"name":"Newsletter : Newsletter"},{"classID":92,"name":"Parution"},{"classID":27,"name":"Poll"},{"classID":47,"name":"Portail : Canal"},{"classID":45,"name":"Portail : Racine"},{"classID":53,"name":"Portail : Th\u00e8me"},{"classID":185,"name":"Portrait"},{"classID":163,"name":"Portrait Old"},{"classID":87,"name":"Presse : Accueil public"},{"classID":108,"name":"Presse : Biographie"},{"classID":91,"name":"Presse : Communiqu\u00e9"},{"classID":118,"name":"Presse : Dossier 'Biographies'"},{"classID":112,"name":"Presse : Dossier 'Communiqu\u00e9s'"},{"classID":115,"name":"Presse : Dossier 'Dossiers de presse'"},{"classID":203,"name":"Presse : Dossier 'Kits de presse'"},{"classID":107,"name":"Presse : Dossier de presse"},{"classID":63,"name":"Presse : Inscription"},{"classID":205,"name":"Presse : Kit de presse"},{"classID":51,"name":"Presse : Racine"},{"classID":21,"name":"Product"},{"classID":32,"name":"Quicktime"},{"classID":73,"name":"Quiz : Accueil"},{"classID":74,"name":"Quiz : Question"},{"classID":195,"name":"Quiz : question - r\u00e9ponse"},{"classID":75,"name":"Quiz : R\u00e9ponse"},{"classID":69,"name":"Racine"},{"classID":34,"name":"Real video"},{"classID":179,"name":"RH : Annonce permanente"},{"classID":176,"name":"RH : Annonce temporaire"},{"classID":181,"name":"RH : Article simple"},{"classID":172,"name":"RH : Campagne permanente"},{"classID":180,"name":"RH : Campagne temporaire"},{"classID":207,"name":"RH : Connexion Espagnole"},{"classID":187,"name":"RH : Discipline scientifique"},{"classID":193,"name":"RH : Domaine professionnel"},{"classID":165,"name":"RH : dossier 'Portraits'"},{"classID":177,"name":"RH : Dossier Reportages"},{"classID":183,"name":"RH : Fichier description"},{"classID":184,"name":"RH : Fichier inscription"},{"classID":178,"name":"RH : Folder annonces"},{"classID":197,"name":"RH : mobilit\u00e9 internationale"},{"classID":171,"name":"RH : Proc\u00e9dure"},{"classID":49,"name":"RH : Racine"},{"classID":175,"name":"RH : R\u00e9gion"},{"classID":167,"name":"RH : Rubrique"},{"classID":164,"name":"RH : Rubrique 'Actu'"},{"classID":170,"name":"RH : Rubrique emploi"},{"classID":174,"name":"RH : textes candidatures"},{"classID":189,"name":"RH : Type d'annonce"},{"classID":191,"name":"RH : Type nature de contrat"},{"classID":106,"name":"RSS : Flux"},{"classID":129,"name":"Rubrique texte simple"},{"classID":146,"name":"SEO : Robots txt"},{"classID":147,"name":"SEO : Sitemap xml"},{"classID":151,"name":"SEO : Valeurs par d\u00e9faut"},{"classID":44,"name":"Silverlight"},{"classID":166,"name":"Sites : Rubrique"},{"classID":33,"name":"Windows media"},{"classID":182,"name":"Xiti : Identifiants Home"}]'
is_container string 1
Plant Health and Environment
Associated Centre(s):
Versailles-Grignon

Rapeseed phoma stem canker

On a global scale, phoma stem canker (or necrosis of rapeseed crown) is one of the most devastating diseases of rapeseed, known to cut yields by up to 50%. While combatting the pathogen by chemical means is not very effective, the use of rapeseed varieties that are naturally resistant to Leptosphaeria maculans, the fungus that causes the infection, is widespread.