Selection of Plant Material in Orchards

Technical articles

Climate resilience

Header photo: Bergarouge ® apricot variety resistant to Sharka virus - © CEP Innovation

1. Presentation

Characterization of the technique

Description of the technique:

Information originally from the Guide for the design of fruit production systems economical in phytosanitary products (2014) / Technical sheet no. 6. For more information see link

The principle:

Genetic control consists of using plant material (varieties and/or rootstocks) selected for its resistance (characteristics that prohibit or limit the development of a bio-aggressor) total or partial to certain bio-aggressors or for its physiological characteristics allowing to control bio-aggressors or reduce symptoms.

There are differences in sensitivity of genetic material (varieties and rootstocks) to bio-aggressors within fruit species. For each fruit species, these sensitivity differences are more or less valued within the currently marketed varietal range. Refer to the documents cited in the references to know the differences in behavior of varieties towards bio-aggressors, as this information allows adapting the level of phytosanitary protection (e.g., reducing interventions on less sensitive varieties).

The pressure of bio-aggressors is also linked to pedoclimatic, environmental factors and the history of the plots. This induces regional variability in the expression of sensitivities of genetic material. Generally, pest expression will be higher in regions that are warm and dry, and disease expression will be higher in regions that are humid. The criteria for choosing varieties and rootstocks will therefore differ according to regions.

Details on the technique:

Plant material with "total" resistance

The use of resistant plant material, often based on monogenic resistance, i.e., on a single major gene, must be combined with other alternative (or chemical) control methods to reduce the risk of bypass by bio-aggressors (appearance of virulent pathogen strains), especially since resistant varieties can become very sensitive once the resistance gene is bypassed (e.g., Ariane® or Goldrush® having the Vf gene for apple scab resistance). Other resistant varieties may however remain less sensitive once the gene is bypassed (e.g., Pitchounette ® having the Vf gene for apple scab), because the major resistance gene is probably associated with other resistance genes or with the plant's ability to tolerate inflicted damage (tolerance).

Difference in sensitivity of plant material (partial resistance)

Polygenic resistances, i.e., based on several genes, confer, depending on the varieties, a partial resistance more or less high against bio-aggressors. This resistance is generally stable (several genes must be bypassed to lose the resistance trait), which gives it durability. Due to the partial nature of polygenic resistance, the use of plant material must often be combined with other control methods (alternative or chemical) or adapted practices.

Implementation period

Spatial scale of implementation

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4. Organisms favored or disadvantaged

Bioagressors favored

Organism	Impact of the technique	Type	Details

Bioagressors disadvantaged

Organism	Impact of the technique	Type	Details

Auxiliaries favored

Organism	Impact of the technique	Type	Details

Auxiliaries disadvantaged

Organism	Impact of the technique	Type	Details

Climatic and physiological accidents favored

Organism	Impact of the technique	Details

Climatic and physiological accidents disadvantaged

Organism	Impact of the technique	Details

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5. For more information

• The Apricot

  -Lichou J., Jay M.

Ctifl, Book, 2012

Ctifl editions, Paris, Monograph collection, 568 p.

• The Mirabelle

  -Gigleux C.

Ctifl, Book, 1996

Ctifl editions, Paris, Monograph collection, 212 p.

• Leaf curl: peach and nectarine: Varietal sensitivity to diseases and pests: "Old and new varieties" - Sheet no. 9

  -Gomez et al.

Fruit Arboriculture, 672., Technical brochure, 2012

• Rust: apricot: "Classic varieties" - Sheet no. 4

  -Broquaire et al.

Arboriculture, 662., Technical brochure, 2011

• Scab: apricot: "Classic varieties" - Sheet no. 5

  -Brun et al.

Fruit Arboriculture, 663., Technical brochure, 2012

• Scab: apple: Old and new varieties in organic farming - Sheet no. 6

  -Gomez et al.

Fruit Arboriculture, 664., Technical brochure, 2012

• Scab: apple: Varietal sensitivity to diseases and pests: "Less sensitive" varieties - Sheet no. 10

  -Brun et al.

Fruit Arboriculture, 673., Technical brochure, 2012

• The Blackcurrant

  -Trillot M., Bore J.-M., Dupin J.-P., Massardier P.

Ctifl, Book, 2001

Ctifl editions, Paris, Monograph collection, 170 p.

• The Cherry tree: table cherry

  -Edin M., Lichou J.

Ctifl, Book, 1990

Ctifl editions, Paris, Monograph collection, 361 p.

• The Raspberry

  -Edin M., Gaillard P., Massardier P.

Ctifl, Book, 1999

Ctifl editions, Paris, Monograph collection, 208 p.

• The Kiwi

  -Hennion B., Floc’Hlay F., Hutin C., Mazollier J., Vaysse P., Baudry A., Fournier J.-M

Ctifl, Book, 2003

Ctifl editions, Paris, Monograph collection, 250 p.

• The Olive tree

  -Argenson C., Regis S., Vaysse P.

Ctifl,, Book, 1999

Ctifl editions, Paris, Monograph collection, 204 p.

• Powdery mildew: apple: Varietal sensitivity to diseases and pests: "Less sensitive" varieties - Sheet no. 11

  -Combe F., Laget E., Brun L.

Fruit Arboriculture, 671., Technical brochure, 2013

• Moniliosis on flower: apricot: "Classic varieties" - Sheet no. 3

  -Parveaud et al.

Fruit Arboriculture, 661., Technical brochure, 2011

• Blueberries, currants and wild fruits

  -Tillard S.

Ctifl, Book, 1999

Ctifl editions, Paris, Monograph collection, 128 p.

• Powdery mildew: apple: "Old and new varieties in organic farming" - Sheet no. 8

  -Gomez et al.

Fruit Arboriculture, 666., Technical brochure, 2012

• Ash-grey aphid: apple: Varietal sensitivity to diseases and pests: Old and new varieties in organic farming. - Sheet no. 7

  -Gomez et al.

Fruit Arboriculture, 665., Technical brochure, 2012

• Chestnuts and marrons

  -Breisch H.

Ctifl, Book, 1995

Ctifl editions, Paris, Monograph collection, 237 p.

• The Hazelnut

  -Germain E., Sarraquigne J.-P., Breisch H., Hutin C., Leglise P., De Taffin H.

Ctifl, Book, 2004

Ctifl editions, Paris, Monograph collection, 298 p.

• The Walnut

  -Germain E., Prunet J.-P., Garcin A.

Ctifl, Book, 1999

Ctifl editions, Paris, Monograph collection, 280 p.

• The Pear tree

  -Masseron A., Trillot M.

Ctifl, Book, 1991

Ctifl editions, Paris, Monograph collection, 224 p.

• The Apple tree

  -Trillot M., Masseron A., Mathieu V., Bergougnoux F., Hutin C., Lespinasse Y.

Ctifl, Book, 2002

Ctifl editions, Paris, Monograph collection, 290 p.

• The Peach tree

  -Hilaire C., Giauque P., Mathieu V., Soing P., Osaer A., Scandella D., Lichou J., Maillard F., Hutin C.

Ctifl, Book, 2003

Ctifl editions, Paris, Monograph collection, 282 p.

• The Table grape

  -Vidaud J., Charmond S., Wagner R.

Ctifl, Book, 1993

Ctifl editions, Paris, Monograph collection, 264 p.

• Bacterial canker: apricot: "New varieties" - Sheet no. 2

  -Delaunay et al.

Fruit Arboriculture, 660., Technical brochure, 2011

• Bacterial canker: apricot: "Classic varieties" - Sheet no. 1

  -Brun et al.

Fruit Arboriculture, 659., Technical brochure, 2011

• The Almond tree

  -Grasselly C., Duval H.

Ctifl, Book, 1997

Ctifl editions, Paris, Monograph collection, 167 p.

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6. Keywords

Bioagressor control method: Genetic control

Mode of action:

Type of strategy regarding pesticide use:

Annexes

S'applique aux cultures suivantes

• Arboriculture and small fruits