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)