Melon aphid resistance management

Melon aphid
Aphis gossypii can become
resistant to many insecticides.
(Photo: Clemson University,

N.A. Martin1 and P.J. Cameron2
1Crop and Food Research, Private Bag 92169, Auckland, New Zealand
220 Westminster Rd, Mt Eden, Auckland 1003, New Zealand

(Revised October 2004)

Reason for strategy and update

Melon aphid, Aphis gossypii, also known as cotton aphid, is capable of becoming resistant to a wide range of insecticide groups. Pest management strategies aimed at preventing or minimising resistance will help maintain control and conserve the effectiveness of existing products. This is an update of the resistance management strategy (Martin & Cameron 1997).


Melon aphid is a polyphagous species that can transmit some plant damaging viruses. It has been recorded from more than 50 plant families (Steenis 1995). Melon aphid has a variety of life cycle strategies and it is not known if any populations require special overwintering hosts or if sexual forms occur in New Zealand.

Melon aphid (Aphis gossypii) has an indefinite number of anholocyclic lines (asexually reproducing populations), some of which may have particular host associations (Blackman & Eastop 1984). Each line can have distinct and different host plant preferences.

Melon aphid can transmit over 50 viruses (Blackman & Eastop 1984) including water melon mosaic virus (WMV) and zucchini yellow mosaic virus (ZVMV), which occur in New Zealand. Because feeding damage is less significant than virus infection, it is possible to tolerate larger melon aphid populations when virus sources are removed or reduced.

Products with label claims for melon aphid control in New Zealand

Table 1: Products with label claims for Aphis glossypii (melon aphid) control in New Zealand (October 2002). For a summary of the details of the claims for each crop see Table 2.
Pesticide categoryIRAC chemical groupPesticide common and (product) names
Parasites   Aphidius colmani (Aphidius, Aphipar)
Predators   Aphidoletes aphidimyza (Aphidoletes)
Carbamate 1A methomyl (Lannate)
pirimicarb (Pirimor)
Organo-phosphate 1B acephate (Lancer, Orthene)
acephate and triforine (Saprene)
chlorpyrifos (Chlorpyriphos, Lorsban, Pychlorex, Spectrum)
diazinon (Basudin, Dew, Diazinon, Diazinyl, Gesapon)
dichlorvos (Nuvos)
dimethoate (Rogor)
maldison (Malathion, Yates Maldison)
methamidophos (Metafort)
terbufos (No longer registered)
thimet (No longer registered)
Organophosphates/pyrethroids 1B/3 pirimiphos-methyl + permethrin (Attack) mixture
Cyclodiene 2A endosulfan (No longer registered)
Pyrethroid 3 alpha-cypermethrin (Bestseller, Dominex, Fastac)
bifenthrin (Talstar)
deltamethrin (Decis Forte, Deltaphar)
taufluvalinate (Mavrik, Supershield, Guardall)
Pyrethrins 3 pyrethrum (Garlic & Pyrethrum, Yates Pyrethrum)
Chloronicotinyl 4A imidacloprid (Confidor 5GR, Gaucho)

Current status of melon aphid resistance in New Zealand

In New Zealand, a population of melon aphids has been found with resistance to methomyl, demeton-S-methyl and acephate (Martin & Workman 1997).

Overseas, melon aphid is resistant to a wide variety of insecticides, including organochlorines, many organo-phosphates, carbamates and synthetic pyrethroids (e.g. Georghiou 1981; Hollingsworth et al. 1994; Silver et al. 1995).

Resistance management and prevention strategy

The general strategy aims to reduce the need for control of melon aphid by reducing virus sources and aphid reservoirs. Selection pressure on aphids in crops can then be reduced by applying insecticides only when necessary to reduce feeding damage.

Note: Control failure does not always imply resistance.

The following guidelines are recommended:

Research strategy

The distribution of resistance among the major cropping areas should be assessed regularly.

Table 2: Products with label claims for control of Aphis glossypii, melon aphid (MA), in New Zealand (October 2002). Not all products listed for each pesticide may have a label claim for all crops indicated. Pesticide category and IRAC chemical group are given in bold. Product names are in Table 1.
 Type of label claim for each crop1
Pesticide category
and IRAC chemical group

Pesticide common and (product) names
Beans Cucurbits Lettuce Potatoes Tomatoes Vegetable and forage brassicas Vegetable crops Fruit crops Strawberries Tamarillo Ornamentals
Aphidius colmani             A in GH       A in GH
Aphidoletes aphidimyza             A in GH       A in GH
Carbamates 1A
methomyl GPA   GPA   GPA GPA in VB     A   GPA
pirimicarb A A A A A A          
Organo-phosphate 1B
acephate     A A   GPA       A A
acephate and triforine                     A
chlorpyrifos   A in SQ       A         A
diazinon A   A   A A in VB A A in CIT A A A
dichlorvos           A A   A in BF   A
dimethoate   A in MW   A   CA in VB, A in FB     A    
maldison           A A       A
methamidophos A     A              
terbufos (No longer registered)           A in FB          
thimet (No longer registered)   A   A   A     A   A
organo-phosphates + pyrethroids 1B/3
pirimiphos-methyl + permethrin mixture   A in GH     A in GH A in VB          
Cyclodiene 2A
endosulfan       A A A in VB     A   A
Pyrethroids 3
alpha-cypermethrin         A            
bifenthrin   A     A           A
deltamethrin   A in SQ                  
taufluvalinate         GPA         GPA A
Pyrethrins 3
pyrethrum             A A     A
Chloronicotinyl 4A
imidacloprid (Confidor 5GR)             A in TSP       A in TSP
imidacloprid (Gaucho)   A in SQ   A   A in FB          

1A = aphids, GPA = green peach aphid (Myzus persicae), CA = cabbage aphid, VB = vegetable brassicas, FB = forage brassicas, BF = berry fruit, GH = greenhouses, TSP = transplants, CIT = citrus, SQ = squash, MW = marrow. Beans excludes broad beans.



Blackman RL, Eastop VE 1984. Aphids on world crops: an identification and information guide. John Wiley & Sons, Chichester, UK.

Georghiou GP 1981. The occurrence of resistance to pesticides in arthropods, an index of cases reported through 1980. FAO of UN, Rome. 172 pp.

Hollingsworth RG, Tabashnik BE, Ullman DE, Johnson MW, Messing R 1994. Resistance of Aphis gossypii (Homoptera: Aphididae) to insecticides in Hawaii: spatial patterns and relationship to insecticide use. J. Economic Entomoogy 87: 293-300.

Martin NA, Cameron PJ 1997. Melon aphid resistance management strategy. Proceedings 50th N Z Plant Protection Conference: 551-555.

Martin NA, Workman PJ 1997. Melon aphid (Aphis gossypii): resistance to pesticides. Proceedings 50th N Z Plant Protection Conference: 405-408.

Silver ARJ, van Emden HF, Battersby M 1995. A biochemical mechanism of resistance to pirimicarb in two glasshouse clones of Aphis gossypii. Pesticide Science 43: 21-29.

van Steenis M 1995. Evaluation and application of parasitoids for biological control of Aphis gossypii in glasshouse cucumber crops. Ph. D. Thesis, Wageningen, Netherlands.