Spider mite resistance management strategy

European red mite
European red mite eggs
on the calyx of an apple.
(Photo: www.hortnet.co.nz)

R.B. Chapman1 and N.A. Martin2
1Soil Plant and Ecology Division, PO Box 94, Lincoln University, Canterbury, New Zealand
2Crop & Food Research, Private Bag 92 169, Auckland, New Zealand

(Revised October 2004)

Reasons for strategy and update

Spider mites are well known for their capacity to develop resistance to many classes of insecticide and miticide. Due to the inherent variation among spider mite populations, it is difficult to generalise about resistance development, cross-resistance patterns and other aspects related to miticide resistance. Resistance management strategies for spider mites may delay the onset of resistance, or suggest alternative management approaches when resistance has developed. However, expert assistance should always be sought when resistance problems arise. 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 earlier resistance management strategy (Insecticide and Miticide Resistance Task Group, 1996).

Background

Spider mites are a group of plant feeding mites that belong to the family Tetranychidae. Some species can be severe pests on fruit trees, greenhouse vegetable and flower crops. Outbreaks of mites are often associated with the use of pesticides used to kill insects, but which also kill the mites' natural enemies.

In New Zealand, the most common spider mite pests belong to two genera, Panonychus and Tetranychus. Pannonychus species produce little webbing, while Tetranychus species often produce much webbing. The species are difficult to distinguish morphologically. Red Tetranychus species are likely to be banana mite or bean mite. The presence of T. cinnabarinus in New Zealand requires confirmation (Zhang 2002). The life cycle of all species comprises an egg stage, larval stage, two nympal stages and adult. Most miticides kill only the active stages (larva, nymphs, and adult mites). However, the relative effectiveness of miticides against immature and adult stages differs between miticides. Some miticides kill only the egg stage or have an ovi-larvicidal action.

Table 1: Spider mite pest species in New Zealand.
SpeciesCommon nameCommon abbreviation
Eotetranychus seximaculatus six-spotted mite  
Panonychus citri citrus red mite CRM
Panonychus ulmi European red mite ERM
Tetranychus cinnabarinus1 carmine spider mite  
Tetranychus lambi banana mite  
Tetranychus ludeni bean mite  
Tetranychus urticae two-spotted spider mite TSM

1The presence of this species in New Zealand requires confirmation.

Products with label claims for spider mite control in New Zealand

Products with label claims for control of spider mites can be divided into three broad groups: mineral oils, insecticides (mainly organophosphates) and specific miticides. Many products that previously had label claims may no longer be effective. Products currently available in New Zealand that have label claims for miticidal activity are listed in Table 2.

Table 2: Products with label claims for mite control in New Zealand (revised March 2003). M = mites, CRM = citrus red mite, ERM = European red mite, TSM = two-spotted mite, GH = greenhouses.
 Type of label claim for each crop1
Pesticide category
and IRAC chemical group


Pesticide common and (product) names
Berryfruit Citrus Grape Hops Pipfruit Stonefruit/summerfruit Ornamentals/flowers Vegetable
Biological control
Phytoseiulus persimilis (Mite-E, Spidex) TSM   TSM TSM TSM TSM TSM TSM in GH
Fatty acid
Fatty acid - potassium salts (Natrasoap)           ERM TSM    
Mineral oil
mineral oil (BP crop oil, Caltex winter spray oil, DC-Tron, Mobil Superior)   CRM     ERM ERM    
Sunspray   CRM M   ERM ERM    
JMS Stylet Oil     M          
Carbamate 1A
oxamyl (Vydate)         ERM      
Organo-phosphate 1B
dichlorvos (Nuvos) M           M M
Bridged diphenyls 2B
dicofol (Kelthane) M M M   M M   M
bromopropylate (Neoron) ERM TSM       ERM TSM ERM TSM    
Pyrethroid 3
tau-fluvalinate (Mavrik Aquaflow)             ERM TSM  
bifenthrin (Talstar)             TSM  
Avermectin, emamectin 6A
abamectin (Agrimec, Avid) TSM       ERM TSM   TSM TSM in GH
Milbemectin (Mit e mec)         ERM TSM      
Ovicides 10A
clofentezine (Apollo) TSM CRM TSM in GH TSM ERM ERM    
Organotin 12B
azocyclotin (Peropal) TSM CRM TSM   ERM TSM ERM TSM    
fenbutatin oxide (No longer registered)         ERM TSM ERM TSM    
14
propargite (Omite) TSM CRM ERM TSM TSM ERM TSM ERM TSM    
Phenoxy-pyrazol 21A
fenpyroximate (Fenamite)         ERM TSM      

1 Label claim may not be for all crops in the crop group. Check label of each product.

Current status of spider mite resistance in New Zealand

European red mite (ERM) resistance to the organotin miticides, e.g. azocyclotin, has developed at some locations in New Zealand (Bowie et al. 1988). Cross-resistance to fenbutatin oxide has also probably developed. ERM and two-spotted spider mite (TSM) resistance to propargite has also developed at some locations (Bowie et al. 1988; Chapman & Penman 1984; Kabir et al. 1991; Kabir et al. 1993). ERM resistance to dicofol has probably developed at some locations (Collyer & Geldermalsen 1975). While resistance to specific miticides is not thought to be widespread in New Zealand, excessive repeated applications (more than 3 applications per crop, per 12 month period or more than one application per season for ovicides and fenpyroximate) of miticides could lead to resistant populations becoming more prevalent.

Several isolated cases of ERM resistance to the ovicides (clofentezine, hexythiazox) have been detected in New Zealand. Ovicide resistant TSM occur in Australia (Edge et al. 1987) and Spain (B. Ehrke, Schering AG, Agrochemical Division, Berlin, pers. comm.) and USA (Reissig & Hull 1991). Cross-resistance between clofentezine and hexythiazox has been established (Cranham & Helle 1985).

Resistance to bromopropylate, dienochlor, tau-fluvalinate and mineral oils has not been detected in New Zealand.

Citrus red mite (CRM) resistant to the ovicide hexythiazox has been found at single sites in New Zealand, and miticide resistance for this species has also been found overseas (Cranham & Helle 1985).

Although spider mite resistance to newer miticide classes, e.g. mitochondrial electron transport inhibitors (METI) (e.g. tebufenpyrad, fenypyroximate) and chloride channel activators (e.g. avermectin, emamectin) is not known in New Zealand, resistance to miticides in these groups is known overseas (e.g. Beers et al. 1998; Devine et al. 2001; Naeun et al. 2001). Cross-resistance between miticide groups is also known. For example, an Australian TSM strain highly resistant to hexythiazox and clofentezine was more tolerant of fenpyroximate and pyridaben than a susceptible strain (Naeun et al. 2001). A dicofol resistant strain in Korea also showed cross-resistance to tebufenpyrad (Kim et al. 1999). These findings suggest care should be taken when selecting newer miticides to overcome resistance to older miticides.

Abamectin has been used widely by greenhouse flower growers to control TSM. Some growers have reported loss of control with this product. Resistance to this product by TSM is known overseas (Beers et al. 1998).

Resistance management and prevention strategy

Guidelines to reduce the risk of miticide resistance include the following:

Note: Control failure does not always imply resistance.

Implementation

The following recommendations are made:

Crop recommendations

The following options are available for the design of spray programmes.

Note: All products listed may not be suitable for crops being exported to certain markets. Check with your export agency before applying any pesticide on export crops. Observe withholding periods.

Pipfruit: apples, pears and nashi.
An integrated fruit production programme is available for apples using Typhlodromus pyri and Phytoseiulus persimilis.

Summerfruit (Stonefruit)
An integrated mite control programme is available for apples using Typhlodromus pyri and Phytoseiulus persimilis.

Strawberry

Other berryfruit
Check labels as not all products have label claims for all crops.
Use either azocyclotin, or bromopropylate, or clofentezine, or propargite.
Ensure thorough coverage and avoid excessive repeated applications (no more than one clofentezine or no more than three azocyclotin, bromopropylate, or propargite spray(s) per crop, per 12 month period).

Grapes
Use either azocyclotin, or clofentezine, or dicofol, or propargite.
Ensure thorough coverage and avoid excessive repeated applications (no more than one clofentezine and no more than three azocyclotin, dicofol and propargite spray(s) per crop, per 12 month period).

Hops
Use either clofentezine or propargite.
Ensure thorough coverage and avoid excessive repeated applications (no more than one clofentezine and no more than three propargite spray(s) per crop, per 12 month period).

Ornamentals
Integrated pest management (IPM) programmes using Phytoseiulus persimilis are available for some flower crops.
If predators cannot be used apply miticides according to label instructions. Use either abamectin, or tau-fluvalinate.
Ensure thorough coverage and avoid excessive repeated applications (no more than three sprays per crop, per 12 month period).

Glasshouse vegetable crops
Integrated pest management programmes using Phytoseiulus persimilis are available for most vegetable crops.
Use abamectin or dicofol.
Ensure thorough coverage and avoid excessive repeated application (no more than three sprays per crop, per 12 month period).

Acknowledgements

Thanks for help from G. McLaren, HortResarch.

References

Beers EH, Riedhl H, Dunley JE 1998. Resistance to abamectin and reversion to susceptibility to fenbutatin oxide in spider mite (Acari: Tetranychicae) populations in the Pacific Northwest. Journal of Economic Entomology 91: 352-360.

Bowie MH, Chapman RB, Walker JTS 1988. Monitoring azocyclotin and propargite resistance in European red mite. Proceedings of the 41st New Zealand Weed and Pest Control Conference: 189-192.

Chapman RB, Penman DR 1984. Resistance to propargite by European red mite and two-spotted mite. New Zealand Journal of Agricultural Research 27: 103-105.

Chapman RB, Penman DR, Walker JTS 1987. European red mite resistance to organotin miticides in Hawkes Bay apple orchards. Proceedings of the 40th New Zealand Weed and Pest Control Conference: 94-98.

Collyer E, van Geldermalsen M 1975. Integrated control of apple pests in New Zealand. 1. Outline of experiment and general results. New Zealand Journal Zoology 2: 101-134.

Cranham JE, Helle W 1985. Pesticide resistance in Tetranychidae. In: Hell W, Sabelis MW ed. World Crop Pests - Spider mites: Their Biology, Natural Enemies and Control, Volume 1B. Elsevier, Oxford.

Devine GJ, Barber M, Denholm I 2001. Incidence and inheritance of resistance to METI-acaricides in European strains of two-spotted spider mite (Tetranychus urticae)(Acari: Tetranychidae). Pest Management Science 57: 443-448.

Edge VE, Rophail J, James DG 1987. Acaricide resistance in two-spotted mite, Tetranychus urticae in Australian horticultural crops. In: Thwaite WG ed. Proceedings of the Symposium on Mite Control in Horticultural Crops, Orange, NSW, Australia. Pp. 87-91.

Insecticide and Miticide Resistance Task Group 1996. Spider Mite Resistance management Strategy. In: Bourdot GW, Suckling DM ed. Pesticide Resistance: Prevention and Management. New Zealand Plant Protection Society, Lincoln, New Zealand. Pp. 177-183.

Kabir KH, Chapman RB, Penman DR 1991. Use of a discriminating concentration form monitoring propargite resistance in twospotted spider mite. Proceedings of the 44th New Zealand Weed and Pest Control Conference: 252-256.

Kabir KH, Chapman RB, Penman DR 1993. Monitoring propargite resistance in European red mite Panonychus ulmi (Acari: Tetranychidae). New Zealand Journal of Crop and Horticultural Science 21: 133-138.

Kim Y-J, Lee H-S, Lee S-W, Kim G-H, Ahn Y-J 1999. Toxicity of tebufenpyrad to Tetranychus urticae (Acari:Tetranychidae) and Amblyseius womersleyi (Acari: Phytoseiidae) under laboratory and field conditions. Journal of Economic Entomology 92: 187-192.

Nauen R, Stumpf N, Elbert A, Zebitz C, Kraus W 2001. Acaricide toxicity and resistance in larvae of different strains of Tetranychus urticae and Panonychus ulmi (Acari: Tetranychidae). Pest Management Science 57: 253-261.

Reissig HW, Hull LA 1991. Hexathiazox resistance in a field population of European red mite (Acari: Tetranychidae) on apples. Journal of Economic Entomology 84: 727-735.

Zhang Z-Q 2002. Taxonomy of Tetranychus ludeni (Acari: Tetranychidae) in New Zealand and its ecology on Sechium edule. New Zealand Entomologist 25: 27-34.