Management of grapevine gene-banks and prevention from virus...
Transcript of Management of grapevine gene-banks and prevention from virus...
Meeting of COST Actions FA1003 & FA0807
Phytoplasmas and viruses management in Grapevine Collections forGermplasm Conservation, Mobilization and Evaluation
8‐9 May 2012, SOFIA (BULGARIA)
La Notte P., Venerito P., Savino V., Martelli G.P.
Centro Ricerca e Sperimentazione in Agricoltura “Basile Caramia”
Istituto di Virologia VegetaleCNR Sezione di Bari
Management of grapevine gene-banksand prevention from virus infections
The risk of virus infection and the control measures to keep unmodified the sanitary status of plants in the experimental fields vary according with the type and value of the material to be retained/evaluated as well as the place of collection and the local climatic conditions
• varietal collections for different purposes (i.e. rare autochthonous germplasm)
• collection of accessions deriving from clonal selection programmes
• collection of parentals for breeding activities
• comparison/ evaluation plot for clones, varieties, new crosses and candidate new varieties
• primary sources /initial materials of certified clones
Depending on their frequency, distribution, harmfulness and epidemiology, among the
high number of viruses reported on grapevine only few represent a real risk for
the reinfection and the evaluation in the gene banks. They are those associated with the
three most dangerous diseases considered by the European legislation on certification
of grapevine propagation material
Infectious degeneration disease (Nepoviruses)
Leafroll disease Rugose wood disease
Fanleaf degeneration is transmitted by:
infected propagation material
nematode vectors
Nematode (“soil” mediated) transmission
Ordine: DorylaimidaFamiglia: Longidoridae
Molto diffuso in Italia
NematodeNematodevettore:vettore:
XiphinemaXiphinemaindexindex
Grapevine Grapevine fanleaffanleafvirus and virus and itsitsspecificspecific vectorvector
unknownBLMoV Blueberry leaf mottle virus
Xiphinema americanum, X. bricolensis, rivesi, californicum, targanense, intermedium
ToRSV Tomato ringspot virus
Xiphinema americanum, Longidorus diadecturus, L. elongatus
TRSV Tobacco ringspot virus
Xiphinema americanumPRMV Peach rosette mosaic virus
unknownTKGDefV Grapevine deformation virus
unknownTKGARSV Grapevine Anatolian ringspot virus
unknownDCLRV Cherry leafroll virus
unknownTUGTRSV Grapevine Tunisian ringspot virus
unknownBG, HU, SRGBLV Grapevine Bulgarian latent virus
Unknown (X. index ?)HU-CZ-CR-AUGCMV Grapevine chrome mosaic virus
Paralongidorus maximusDRpRSV Raspberry ringspot virus
Longidorus attenuatusD, YU, IL, TK, CATBRV Tomato blackring virus
Longidorus apulus (only on vegetables)ITAILV Artichoke Italian latent virus
D, IT, TK, PTSLRSV Strawberry latent ringspot virus
Xiphinema diversicaudatumEUArMV
Arabis mosaic virus
Xiphinema index, (X. italiae and X. vuittenezi ?)
EU, CaliforniaGFLV Grapevine fanleaf virus
16 viruses (11 Europe)
Transmission of leafroll and rugose wood bynot flying insects vectors
GLRaVGLRaV--1: 1: Helicoccus bohemicus,Phenacoccus acerisPhenacoccus acerisParthenolecanium corni, Parthenolecanium corni, Neopulvinaria Neopulvinaria innumerabilisinnumerabilis
GLRaVGLRaV--3: 3: Planococcus ficus, Pl. Planococcus ficus, Pl. citricitriPseudococcusPseudococcus longispinuslongispinus..Ps. affinis, PsPs. . calceolariaecalceolariae, , PsPs. viburni, . viburni, PsPs. . maritimusmaritimusPsPs comstockicomstocki, , PulvinariaPulvinariavitisvitis
GLRaVGLRaV--5: 5: PsPs. . longispinuslongispinus
GLRaVGLRaV--9. 9. PsPs. . longispinuslongispinus
GVA: GVA: Planococcus citri, Pl. ficus,Pl. ficus,Pseudococcus longispinus,Pseudococcus longispinus,Ps. affinis, Ps. Ps. affinis, Ps. comstockicomstockiNeopulvinariaNeopulvinaria innumerabilisinnumerabilis
GVB: GVB: Pl. ficus, PsPs. . longispinuslongispinusPsPs. . affinisaffinis, ,
Mealybugs and soft scales
Mealybugs are much more efficient than soft scale in vectoring grapevine viruses in open field
• can transmit and are mobile in all stages
• have a high number of generation x year
• due to their behavior are difficult to control
• the transmission is semipersistent and not very specific. It allows the spread of infection with low population levels as well as the survival of a limited number of adults (hidden under the bark) is able to renew severe infestations.
Once planted a new vineyard the grower has no instruments to repair the
possible damages caused by viruses
The control of virus infection is based on the
PREVENTION
Selection and preparation of primary sorces
Officialregistration of
clones
Pre-multiplicationin vivo or in vitro
MmultiplicationConservation forthe pre-
multiplication
CONTROLLIServizio Controllo Vivai
SanitationSanitation
ThermoterapyThermoterapy Meristem tip cultureMeristem tip culture
PREVENTIVE MEASURES TO BE IMPLEMENTED BEFORE THE ESTABLISHMENT OF A NEW EXPERIMENTAL
VINEYARD
• Use of soil free from nematodes vectors (and fungal root rot agents)
• Control of soil-borne vectors
• Use of propagation material (rootstock and scion) “healty” or controlled to avoid the introduction of new viruses for the area
Controls to carry out before planting• Presence of rootstock shoots (also along the
boundaries) of any preceding vineyard• Nematological analysis (only vector species)• mycological analysis (i.e. Armillaria mellea,
Rosellinia necatrix)
Chemical control of soil-borne vectors ?
Fumigation
Nematocides
LOW EFFICACY IN DEPTH, VERY HIGH COSTS, HIGH ENVIRONMENTAL IMPACT
ELIMINATION OF ALTERNATIVE HOST SPECIES
Fig Pistachio
Ficus carica (Fig)Pistacia vera (Pistachio)Ceratonia siliqua (Carob tree)Prunus domestica (European Plum)Citrus sp. (Citrus) Malus pumila (Apple)Olea europaea (Olive)Salix sp. (Willow)
Brassica oleracea Mill. (Broccoli)Capsicum frutescens L. (Pepper)Fragaria X ananassa (Strawberry)Solanum lycopersicum (Tomato)Solanum tuberosum (Potato)Petunia X hybrida (Petunia)Chenopodium amaranticolorSolanum nigrum
X. diversicaudatum: Apricot, Avocado, Black Currant, Blackberry, Carnation, Celery, Citrus, Juniper, Cucumber, Fig, Garden Raspberry, Nectarine, Okra, Peanut, Pear, Perennial Ryegrass, Petunia, Rose, Soybean, Strawberry, Tomato
Correct grubbing up and replanting of vineyard
• Use of systemic herbicides to kill the vines (optional)• Uproot the vines carefully removing and burning all the roots (with excavator and hand finishing)• 80-100 cm deep plowing• Land left for at least 3 years using vernine cover crops (cereals or fodder)• Summer plowings
- Correct choice of field location (possibly isolated and not placed under the slope of other vineyards)
- Leave a band edge at least of 10 m from other borderingvineyards infected with infectious degeneration and infested by nematode vectors
-Ensure the isolation of surface water from sourrounding vineyards (i.e. digging a ditch)
Isolation of premultiplication fields and mother plant blocks
AND AFTER PLANTING …..
- Use dedicated equipments or clean themcarefully from soil from other fields
Measures, instruments and facilities to prevent or control the reinfection /over-infection
- Avoid to introduce in the gene-banksmaterial infected by nepovirusestransmissible by nematodes
- Monitoring continuously the possible occurrence of new symptoms
- Avoid to overgraft the plants
The populations of mealybugs must be continuously and carefully monitored especially when favorable
climatic conditions occur
Finding very low infestation levels is difficult and therefore the infestation may go unnoticed for several years
• peeling away bark on trunks checking where the adults use to over-winter
• checking on the roots at the base of vine trunk
• using specific pheromone traps to attract (in surrounding vineyards up to 400 m) and capture the males (probably now the best system to determine low infestation rates)
Insecticide for chemical control
• dormant organophosphate insecticide (i.e. chlorpirifos)
• in-season application of oragophosphate or carbammate (i.e. methomyl)
• insect growth regulators i.e. buprofezin (Applaud)
• nicotinoid systemic insecticide (imidacloprid)
N° of application, time of treatment, distribution by drip irrigation (in open field) or foliar treatment (mainly on plant in pots)
Facilities
the surveillance should be very high especially for the mealybugsbut their control is cheaper and much more effective
Seed transmissionCan the seedling be infected after a cross when the parentals are infected ?
• None of the viruses associate with leafroll, rugosewood and fleck is reported to be seed-borne
• GFLV occurs in the pollen and the endosperm but there are conflicting reports on seed transmission. Seed transmission has been reported for most, butnot all, nepoviruses, and BLMoV and CLRV are efficiently transmitted by pollen
Usually the reinfection of new germplasm occurs in the evaluation plot for the common technique to
over-graft adult plants in order to accelerate the fruit set for the first selection
For several viruses the reproduction could be considered as an alternative procedure of sanitation
Evaluation plot for new candidate varieties
It’s strongly suggested to keep the original seedlings self-rooted in pots up to the end of the first evaluation results
Thanks for the attention