root knot nematodes - vinehealth australia · root-knot nematodes (meloidogyne spp.; rkn) are...
Post on 14-Aug-2020
4 Views
Preview:
TRANSCRIPT
Control and Management
Control methods for nematode-infested sites include
planting with nematode resistant rootstocks and
increased water and nutrient inputs.
However, it should be noted that the resistance,
susceptibility and tolerance of rootstocks varies
widely, depending on nematode species and soil type
(Nicol et al. 1999). Nonetheless, grapevine rootstocks
are still the main strategy and management tool used
for management of RKN.
To view the corresponding table by Nicol et al. (1999)
on nematode Resistance (R) Susceptibility (S) and
Tolerance (T) of rootstock cultivars to the Meloidogyne
species please visit our website at
www.phylloxera.com.au
Life cycle
RKN juveniles hatch from eggs and migrate through
the soil to find a host plant root to feed off. Infected
roots develop round swellings or galls, and root rot
occurs; impairing the ability of the vine to take up
nutrients and water from the soil (Nicol and van
Heeswicjk 1997, Nicol et al. 1999, Anwar and McKenry
2002).
In each formed gall several adult females may develop,
each with the ability to lay up to 1500 eggs in a gel
matrix on the root surface. The life cycle takes over a
month to complete, depending on temperature, and
each female has the potential to produce 125 million
progeny per season.
The survival rate of the Meloidogyne species in soil
without a food source is up to 18 months (Nicol et al.
1999), but they can survive on susceptible weeds or
other hosts.
References:
Anwar, S.A., McKenry, M.V. (2002) Developmental response of a resistance breaking population of
Meloidogyne arenaria on Vitis spp. Journal of Nematology 34 (1) 28-33
Loubser, J.T., Meyer, A.J. (1987) Resistance of grapevine rootstocks to Meloidogyne incognita under
field conditions. South African Journal of Enology and Viticulture 8 (2) 70-74
McKenry, M.V. (1984) Grape root phenology relative to control of parasitic nematodes. American
Journal of Enology and Viticulture35 (4) 206-210
Nicol, J.M., Van Heeswijck, R. (1997) Grapevine nematodes: Types, symptoms, sampling and control.
Australian and New Zealand Grapegrower and Winemaker Annual Technical Issue 402a 139-151
Nicol, J.M., Stirling, G.R., Rose, B.J., May, P., Van Heeswijck, R. (1999) Impact of nematodes on
grapevine growth and productivity: current knowledge and future directions, with reference to
Australian viticulture. Australian Journal of Grape and Wine Research 5 109-127
Walker, G.E. (1997) Effects of Meloidogyne spp. and Rhizoctonia solani on the growth of grapevine
rootlings. Journal of Nematology 29 (2) 190-198
Figure 1. The four main Meloidogyne species
Picture:Jonathon Eisenbeck nemapix
vol.1p://www.nematode.net/Species.Summaries/Meloidogyne.javanica/
Symptoms
Plant growth response is a good indicator of
grapevine susceptibility (Loubser and Meyer 1987).
Symptoms of nematode infestation include poor
establishment and shoot growth, and severe
infestation may result in vine death.
Above-ground symptoms may be confused with
either nutritional deficiencies or water stress (Nicol
and van Heeswicjk 1997).
Damage thresholds for RKN in grapevines in a report
by Anwar and McKenry (2002) were found to be
between 1-25 juveniles per 1000ml of soil.
Population densities that exceed this threshold will
significantly reduce growth in susceptible varieties.
Affected vine Healthy Vine
Susceptible soil types
RKN commonly occur on grapevines and other crops in
South Australia, and their spread across soil types is
also quite diverse.
However, RKN are generally more damaging in light,
sandy soils. A survey by PGIBSA (2008) found that RKN
were present vineyards in a number of regions in South
Australia.
Root Knot Nematodes A root-knot nematode factsheet for growers in South Australia
Dr Greg Walker1 Catherine Cox2
1 South Australian Research and Development Institute, Glen Osmond SA 50642Phylloxera and Grape Industry Board of South Australia, 46 Nelson Street Stepney, SA 5069
Introduction
Root-knot nematodes (Meloidogyne spp.; RKN) are
highly damaging pests of grapevine roots (and are the
most widespread and economically-important plant
parasitic nematodes of grapevines in South Australia
(Walker 1997).
There are four main species of root-knot nematodes
associated with grapevines: Meloidogyne incognita,
M. javanica, M. arenaria, M. hapla (Figure 1)
top related