Unité Mixte de Recherche

Campus International
de Baillarguet
34398 Montpellier Cedex 5
Fax : +33 4 99 62 48 08


1st joint research center in France, certifed

Copyright © CIRAD 2009
Visacane, la quarantaine de canne à sucre du Cirad
  contact : isabelle.guinet-brial@cirad.fr
Visacane is CIRAD's sugarcane quarantine service. It supplies disease-free sugarcane varieties worldwide, to the sugar industry and to sugarcane breeding centres.
Transferring varieties in complete safety (pdf file attached)
Sugarcane quarantine
The availability of new sugarcane varieties largely helps to improve farming systems. To that end CIRAD procures access for its partners to germplasm for research and varietal improvement purposes, and to new high-yielding varieties for industrial crops. Planting material is transferred from one place to another in vegetative form in the great majority of cases, which considerably increases the risk of spreading diseases and pests. CIRAD's sugarcane quarantine helps to remove those risks.
A system to guarantee healthy varieties
CIRAD sugarcane quarantine in Montpellier covers the main three quarantine operations: plant material transfers, disease detection, and elimination of pests and diseases. Alongside phytosanitary constraints there are also legal constraints: ensuring, through appropriate contracts, that plant breeders' intellectual property rights over the disseminated material are respected. In practice, introduced plant material passes through three stages during which everything is done to detect any diseases and pests and eliminate them:
• Passage through a chamber meeting BL2-P standards to eliminate any risk of introducing pests considered as quarantine parasites in Europe.
• Two quarantine cycles of 9 to 12 months each, to detect diseases and multiply varieties before their release and dissemination.
The planting material therefore spends at least two years in quarantine.
Sugarcane plants in the  qurantine glasshouse - © J.-C. Girard
Disease detection
Yellow leaf symptoms on  variety H50-7209 - © P. Rott

Disease detection is one of the main quarantine operations. Various detection techniques are used in quarantine: a visual search for symptoms, isolation on selective medium, serological and molecular tests (PCR, RT-PCR). For quarantine purposes, disease detection tools need to be able to identify very small quantities of pathogen and, during the same test, to detect all the variants of the same pathogen, or even of several pathogens.
A major challenge: identifying latent diseases
Three diseases undergo particular surveillance in quarantine because it is often difficult, or even impossible, to detect them by simply observing symptoms. Indeed, leaf scald – due to the bacterium Xanthomonas albilineans – and yellow leaf – due to Sugarcane yellow leaf virus – can go through long periods without any symptoms occurring. For its part, ratoon stunting disease, caused by the bacterium Leifsonia xyli subsp. xyli, never displays any external symptoms during infected plant growth in quarantine glasshouses. Depending on the geographical origin of varieties, it is sometimes necessary to search for a dozen other diseases, primarily of viral or bacterial origin, including phytoplasmas.
Disease elimination

Between two quarantine cycles, all cuttings are systematically subjected to long hot water treatment to eliminate a maximum of bacteria, fungi, insects and mites likely to be harboured by the cuttings. Phytosanitary treatments are also regularly carried out during growing (foliage spraying, watering at the foot of the plant), and at the end of the cycles (soaking of cuttings). If a disease that is difficult to cure is detected, such as leaf scald, the infected varieties are destroyed. However, if the detected disease is considered curable, such as ratoon stunting disease, the varieties are cleared of the disease by long hot water treatment. In the case of sugarcane yellow leaf, or streak mosaic (Sugarcane streak mosaic virus), apical meristem culture has to be carried out to obtain healthy plantlets.

Young sugarcane plantlet derived from apical meristem - © J.-C. Girard
Transferral of varieties
Preparing cuttings for dispatch - © D. Roques
Around a hundred varieties are imported each year from various sugarcane producing countries. On leaving quarantine, around a hundred varieties are transferred each year to different CIRAD partners. Those varieties are used either by the industry for planting, or by research.

They are of different types: already known promising varieties, new varieties for assessment, or belonging to ancestral species.