Effectiveness of Acaricides against Tea Mites

Dicofol, ethion and sulphur formulations have always been found to be effective against pink and purple mites. However, when compared to dicofol, ethion and Sulphur are more effective against these mites. Observations on the effectiveness of the commonly used acaricides against tea mites are summarised in Table 1 and 2. Besides these chemicals a few others such as Quinalphos, Propargite, Fenpyroximate, Fenazaquin, Hexythiazox, Spiromesifen, Paraffinic oil and sulphur are also applied against the eriophyid mites. 

Most of the synthetic pyrethroids, when repeatedly applied at closer interval, led to high build up of pink mites. The synthetic pyrethroid, fenpropathrin could control pink mites, only at high dosage rates. Among the older and unavailable chemicals, cyhexatin (Plictran) was very effective against all tea mites. The chitin inhibitors, diflubenzuron and flufenoxuron were also found to be useful to a limited extent against pink mites.

Table 1. List of chemicals recommended for the control of pink and purple mites

Chemicals	Brand names	Dosage (ml/ha)	MRL (EU) (ppm)
Propargite 57 EC	Omite, Simba, Indomite	500	5
Fenpyroximate 5 EC/SC	Sedna, Mitigate	300	0.1
Fenazaquin 10 EC	Magister	1000	10
Hexythiazox 5.45 EC	Endurer, Maiden	400	4
Spiromesifen 240 SC	Oberon	300	0.02
Lime sulphur	-	1:40	-
Micronised sulphur 52%	-	1500	-
Paraffinic oil	-	1500	-

Table 2. Comparative effectiveness of the commonly used acaricides against tea mites

Chemicals	Pink mite (Acaphylla theae)	Purple mite (Calacarus carinatus)	Scarlet mite (Brevipalpus australis)	Red Spider Mite (Oligonychus coffeae)
Wettable sulphur	Effective	Effective	Effective	Effective
Dicofol	Effective	Effective	Effective	Effective
Ethion	Very effective	Very effective	Effective	Effective
Propargite	Effective	Effective	Very effective	Very effective
Fenpyroximate	Very effective	Very effective	Very effective	Very effective
Fenazaquin	Very effective	Very effective	Very effective	Very effective
Hexythiazox	Very effective	Very effective	Very effective	Very effective
Spiromesifen	Very effective	Very effective	Very effective	Very effective
Lime sulphur	Very effective	Very effective	Very effective	Very effective
Micronised sulphur 52%	Very effective	Very effective	Effective	Effective
Paraffinic oil	Effective	Effective	Effective	Effective